2 Course Outline D-Link NAS (Network Attached Storage) Introduction to Network StorageRAID TechnologiesStorage EssentialsBasic Terminologies and ConceptsHard Drive Interface TechnologiesSAN TechnologiesFiber Channel TechnologyiSCSI TechnologyD-Link SAN (Storage Area Network)D-Link Products for Storage Area NetworkMarket Analysis for D-Link SAM ProductsD-Link SAN ImplementationSAN Product Features OverviewVolume ManagementDevice ManagementiSCSI FeaturesVolume and RAID SupportD-Link NAS (Network Attached Storage)D-Link Products for Network Attached StorageMarket Analysis for D-Link NAS ProductsNAS Product Features OverviewManaging the DeviceUser and Group ManagementAppliance ServersNetwork FeaturesUSB Port ApplicationsApplications and Solutions for Network StorageNAS ApplicationsSAN Applications
4 Introduction to Network Storage After this section, you should gain more knowledge of the following:Types of current storage solutions for computerized devicesCharacteristics of DAS and the challenges of using itCharacteristics of NAS and the benefits/advantages that it offersCharacteristics of SAN and the benefits/advantages that it offersDifferences among each storage solution
5 Evolutions of Storage Technology Introduction to Network StorageStorage EvolutionsEvolutions of Storage Technology19631982194019511956196219701978198119841940s – Data was mostly stored on punched card and punched paper tape.1951 – First computer to use magnetic tape for storage.1956 – IBM introduced the first commercial hard disk drive known as RAMAC (Random Access Method of Accounting and Control).1962 – The laser diode was invented by IBM which became the fundamental technology for read-write optical storage devices.1963 – IBM introduced the first storage unit with removable disks. This became an end for punched-cards era.1970 – Portable storage was born with the invention of the floppy disk.1978 – The first patent for RAID technology was filed.1981 – The Intelligent interface for disk drive “SASI” was developed by Shugart Associates and NCR Corporation. This interface is the predecessor to SCSI interface.1982 – SCSI interface was born and developed based on its predecessor, SASI.1984 – Compaq and Western Digital Co. produced ST506 controller that was able to be mounted on the hard disk drive and connected to the PC using a 40-pin cable.Page is Animated
6 Evolutions of Storage Technology (cont’d) Introduction to Network StorageStorage EvolutionsEvolutions of Storage Technology (cont’d)198620011985199419961998200020031985 – First IDE drive was built by integrating ST506 controller in the hard disk drive.1986 – SCI specification was defined in a ANSI standard X1994 – SCSI-2 became an ANSI standard X and the IDE standard was approved by the ANSI under the name ANSI X1996 – The ATA-2 interface that complied with the ANSI X standard was the AT Attachment Interface with Extensions, and the ATA-2 interface that complied with the ANSI X standard was the AT Attachment Interface with Extensions.1998 – The ATA/ATAPI-4 interface that complied with the ANSO NCITS was the AT Attachment Interface with Packet Interface Extension.2000 – The ATA/ATAPI-5 interface that complied with the ANSI NCITS was the AT Attachment Interface with Packet Interface-5.2000 – The Serial ATA 1.0 Working Group was established to specify Serial ATA for desktop applications.2001 – Serial ATA 1.0 was released in August of 2001 (with subsequent revisions 1.0a and 1.1) which provided significant improvement over parallel ATA.2003 – Hitachi bought IBM Data Storage Division.Page is Animated
7 Types of Storage Solution Introduction to Network StorageStorage SolutionsTypes of Storage SolutionInternal StorageMemory (DDR)IDE ATA Hard Disk / Optical Compact DiskSCSI Hard DiskSATA Hard DiskExternal StorageDirect Attached Storage (DAS)Network StorageNetwork Attached Storage (NAS)Storage Area Network (SAN)USB Storage EnclosureFirewire 1394 Storage EnclosureSlim Disk MemoryStorage can be differentiated into two major types:Internal StorageInternal storage refers to storage media built inside a client device and is attached directly to the backplane of the client device (Computer, notebook/ laptop, etc).Examples for internal storage media are Internal Hard Disks (IDE/PATA, SATA, SCSI), and DDR Memory.Internal hard disks, such as IDE/PATA, SATA, and SCSI HDD, is often considered as a very basic example of Direct Attached Storage (DAS) where the storage media is directly attached to the client device. However, a most of the time the idea of internal storage is that of a storage media built inside a client device, while most DAS refer to an external storage enclosure directly attached to the client side.If based on how a storage media is connected (Directly/ indirectly attached), the internal hard disks are a type of DAS. But if based on location of the storage media, the hard disk will still be a type of internal storage.External StorageExternal storage refers to storage media put outside the client device and usually is an independent (external) storage enclosure.When based on how the storage enclosure is connected to the client side, External Storage can be separated into more categories, which may include:Direct Attached Storage (DAS)Network StorageUSB Storage Enclosure (Portable Hard Disk, USB Flash Disk/ Thumb Drive)Firewire 1394 Storage EnclosureSlim Disk MemoryNote:The DAS that we are referring to in this material is more to an independent external storage enclosure and may not be suitable for internal storage hard disk explanation.
8 Direct Attached Storage (DAS) Introduction to Network StorageStorage SolutionsDirect Attached Storage (DAS)A storage system directly attached to a client (commonly to a computer or server), without a storage network in between.Common example of DAS would be a storage enclosure externally attached to a server, where clients in the network must access the server in order to connect to the storage device.ClientLocalAreaNetworkOracle Database ServerFile ServerActive Directory ServerHost Bus AdapterDAS #1DAS #2DAS #3DAS #4Network Application ServerDAS is the most basic level of storage solution in which storage devices are part of the computer, as with drives; or directly attached to a single server, as with RAID arrays, or tape libraries. Clients in the network must therefore access the server in order to connect to the storage device.DAS is ideal for localized file sharing in small environments with a single server or few servers, such as small businesses or departments; or workgroups that do not need to share the data resources across the entire (enterprise) network.
9 Introduction to Network Storage Storage SolutionsChallenges of DASDifficulty managing servers and storage with slow backup causing heavy LAN congestionLimited number of drives supportedLimitation on storage sizeInability to share storage across multiple serversTime-consuming and complex backup and managementNeed for storage down time (off-line) when installing additional drivesDirect Attached storage is generally how most SMBs start out, since servers have drives built in. As the need for increased storage arises, additional hard drives will often be installed directly into the servers. There are a number of problems with this approach, the largest of which is that the server generally has to be taken off-line while the new drives are being installed. In addition, there is a limit to the number of drives that can be supported by a given server. While Direct Attached Storage arrays and servers with RAID support are available, they are more expensive than standard servers, and still have limitations on overall storage size, ability to share storage across multiple servers, and are time-consuming to manage and backup.With Direct Attached Storage, managing backup is quite difficult. Storage devices are distributed throughout the company, often built into servers and workstations/PCs with different operating systems and usage requirements, making it nearly impossible to create a reliable, automated backup solution. Another major disadvantage of Direct Attached Storage is the difficulty in utilizing the storage efficiently across multiple servers and users. Drives added to one server are generally not easily available to other servers, so as a company’s storage needs grow, management gets increasingly complicated. If a user whose account is on Server1 needs additional storage space, they may not be able to be assigned unused space on Server2 without moving their account. This problem is solved with storage virtualization provided by a network storage.
10 Solution for DAS DAS Network Storage Introduction to Network Storage Storage SolutionsSolution for DASSimplify storage management by separating the data from application server.DAS Network Storage
11 Why Do We Need Network Storage? Introduction to Network StorageStorage SolutionsWhy Do We Need Network Storage?Volume of data keeps growing exponentiallyRedundancy and backup necessityData availability and accessibilityStorage consolidation for centralized management*Increase reliability and better performance (speed)Storage virtualization*Overall cost reductionData Protection* Unique characteristics possessed by SAN only.Advantages of network storage as compared to DAS are as the following:Effective utilization of storage resources through centralized accessSimplified, centralized management of storage which reduces administrative workloadIncreased flexibility and scalabilityImproved throughput performance to shorten data backup and recovery timeNon-disruptive business operations when you add or redeploy storage resourcesHigher data availability for business continuance through a resilient network design
12 Network Attached Storage (NAS) Overview Introduction to Network StorageStorage SolutionsNetwork Attached Storage (NAS) OverviewNAS is a file-level computer data storage device connected to a computer network providing data access to heterogeneous network clients.A NAS unit is essentially a self-contained computer connected to a network, with the sole purpose of supplying file-based data storage services to other devices on the network.NAS are usually accessed by workstations and servers through a network protocol such as TCP/IP and applications such as Network File System (NFS) or Common Internet File System (CIFS) / Server Message Block (SMB) for file access.ClientApplication ServerFile ServerPublic Local Area NetworkNASNAS is a dedicated storage server based on client-server design, just like a file server with storage internally attached to it. NAS can be analogous to a computer but without a monitor, keyboard or mouse. It has its own embedded operating system. One or more drives can be attached to NAS systems to increase its total capacity, but clients will always connect to the NAS box/head, rather than to the individual disk.NAS provides file-sharing to clients and servers in a mix/heterogeneous environment. With DAS, each server is running its own operating platform, so there is no common storage in an environment that may include a mix of Windows, Mac and Linux workstations. NAS systems can integrate into any environment and serve files across all operating platforms.Unlike SAN which connect to a Fiber Channel network, NAS enclosures connect to a TCP/IP network which also include servers and workstation clients. NAS solutions are typically configured as file-serving appliances accessed by workstations and servers through a network protocol such as TCP/IP and applications such as Network File System (NFS) or Common Internet File System (CIFS) for file access.NAS storage scalability is often limited by the size of the self-contained NAS appliance enclosure. Adding another appliance is relatively easy, but sharing the combined contents is not. Because of these constraints, data backups in NAS environments typically are not centralized, and therefore are limited to direct attached devices (such as dedicated tape drives or libraries) or a network-based strategy where the appliance data is backed up to facilities over a corporate or dedicated LAN. Increasingly, NAS appliances are using SANs to solve problems associated with storage expansion, as well as data backup and recovery. NAS does work well for organizations needing to deliver file data to multiple clients over a network. Because most NAS requests are for smaller amounts of data, data can be transferred over long distances efficiently.
13 Storage Area Network (SAN) Overview Introduction to Network StorageStorage SolutionsStorage Area Network (SAN) OverviewA high performance storage network that transfers block-level data between servers and storage devices, separate from the local area network (LAN) traffic.In a SAN environment, storage devices, such as DAS, RAID arrays, or tape libraries are connected to servers using fiber channel or iSCSI.Characteristics of SAN:VirtualizationStorage ConsolidationScalableBlock data transfer uses encapsulated SCSIApplication ServerFile ServerSANHigh performance private storage networkClientPublicLocal Area NetworkSAN is a high performance storage network which transfers block-level data between servers and storage devices, separate from the public local area network traffic.In a SAN environment, storage devices, such as DAS, RAID Arrays, or tape libraries are connected to servers using fiber channel or iSCSI methods.The unique characteristic of SAN is that it moves large blocks of data rather than on the file level (i.e. on as file basis).Characteristics of SAN:Virtualization – refers to the process of grouping together independent storage devices found across a network to create what seems (to the user) to be a single large storage entity that can be centrally managed.Storage Consolidation – Businesses that seek to move beyond Direct Attached Storage (DAS) and are looking for the benefits offered by SAN will appreciate the xStack Storage solution and its ability to support multiple servers and efficiently pool storage. IP interfaces can be tied together using existing fast Ethernet equipment. This reduces costs related to equipment and staff in comparison with direct-attached storage. Companies can also better utilize storage capacity by pooling more servers together in the storage network.Scalable – Additional storage enclosures can be added to the SAN to increase the overall storage capacity.
14 Differences of NAS and SAN Introduction to Network StorageStorage SolutionsDifferences of NAS and SANNetwork Attached Storage (NAS)Storage Area Network (SAN)Clients sees the NAS box as an independent device (as a file server), thus the architecture is client-server based where client requests are sent directly to the NAS.Client sees the SAN as a part of a server (the SAN is connected behind the server in its own network), thus client should send the request to server connected to the SAN.Clients connect to a NAS and share files through the use of NFS, CIFS/SMB, or HTTP protocol.Clients connected to the SAN through the use of iSCSI or Fiber Channel, depending on which is supported by the SAN.File-based data transfer (data is identified by file name and other parameters, such as the file meta-data (file’s owner, permissions, etc)Block-level data transfer along long distances (data is addressed by disk block number and without file system formatting).Backups and mirrors are done on files, not blocks, which provides savings in bandwidth and time.Backups and mirrors require a block by block copy, even if blocks are empty. A mirror machine must be equal to or greater in capacity than the source volume.
15 Comparison for each of the Storage Solutions Introduction to Network StorageStorage SolutionsComparison for each of the Storage SolutionsDAS EnclosureNAS EnclosureSAN EnclosureDirectly connected to a clientConnected to servers and workstations via a pubic networkConnected to servers over the private storage networkSlower data access compared to network storageFast data access (depends on the LAN speed)Fastest data access (depends on which protocol is used)Direct data transferFile level data transferBlock level data transferData transfer using SCSI protocolData transfer using NFS / CIFS / SMB protocolFiber Channel or iSCSI is used for data transfer protocolApplicationServerFileSAN ApplianceHigh performanceprivate storage networkClientPublic LAN
16 Summary: Introduction to Network Storage Clients can choose from three types of storage systems to keep their data on: Direct Attached Storage (DAS), Network Attached Storage (NAS), and Storage Area Network (SAN).Direct Attached Storage (DAS) is the most commonly used data storage solution for end user level client devices (computers, servers). It attaches the storage enclosure directly to the client device.Network Attached Storage (NAS) is mainly targeted for home and SMB users, and offers the benefits of network storage with ease of sharing files and centralized data storage over the IP network.Storage Area Network (SAN) is mainly targeted for Server Farms or Special Applications, e.g. IP Surveillance, and offers high performance network storage solutions for data transfers over enterprise network, with benefits include virtualization, storage consolidation, etc.D-Link supports data transfer over the iSCSI protocol for SAN devices.
17 Questions and Answers: Introduction to Network Storage What is the characteristic of Direct Attached Storage?Storage is connected to the server without being separated with TCP/IP networkStorage consolidation capabilityData transfer using Network File System (NFS) protocolLink multiple storage repositories to multiple clients and serversWhat is the characteristic of D-Link Network Attached Storage?Provide slow data accessBlock data transfer along long distance is possibleData transfer using CIFS/SMB protocolSupport server virtualizationWhat are the characteristics of D-Link Storage Area Network? (Choose Two)File-level data transfer along long distanceStorage is connected directly to the server using iSCSI protocolBlock data transferSupport storage virtualization and consolidationACC, D
19 RAID TechnologiesRAID TechnologiesAfter this section, you should gain more knowledge of the following:RAID mechanisms overviewRAID types supported by D-Link network storage appliancesCharacteristics of each RAID type supported by D-Link as well as the advantages and disadvantages for each (RAID 0, RAID 1, RAID 5, RAID 10, and JBOD)
20 RAID Technology Overview RAID TechnologiesIntroduction to RAIDRAID Technology OverviewRedundant Arrays of Independent Disks (RAID) is a data storage mechanism for dividing and/or replicating data over multiple hard drives, thus which may provide better performance, reliability, and/or larger data volume sizes. Depending on the type of RAID applied, different benefits can be achieved.D-Link network storage supports several RAID technologies as described below:RAID LevelTypeDefinitionRedundantStripedRAID 0Distributes each block of data among several drives to improve the speed of accessNoYesRAID 1MirroredTwo copies of all data are written to independent disksRAID 10Mirrored StripedStripes the data among several drives and then mirrors the data to another set of disksRAID 5ParityDistributes one copy of the data among several drives and adds parity blocks spread throughout the volume to protect against the loss of any single driveN/AJBODAll the disks are grouped together to form one large volume. The data is written to the disks in sequential order
21 RAID 0 Technology Overview RAID TechnologiesRAID 0RAID 0 Technology OverviewCharacteristics of RAID 0RAID 0 works by striping the data (Data-striping) across the hard drivesAt least two hard drives must be providedImproved performance (high speed data transfer)No fault-toleranceNo error-checkingAdvantages and disadvantagesAdvantagesDisadvantagesSpeed enhancement and improve I/O performanceMaximum utilization of storage capacity*Very simple design and easy to implementNo data redundancy or fault-toleranceFailure occurring in any disk of an array will result in all data in that array being lost* Each physical disk must be of the same capacity to achieve 100% storage capacity utilizationCharacteristics of RAID 0:Minimum 2 hard drives is needed for RAID 0.Improved performance with high speed data transferThe greater the number of disks provided in an array, the higher the bandwidth and the faster data transfer rate.I/O performance is also greatly improved by spreading the I/O load across many channels and drivesNo additional overhead, such as parity calculation, which can cause lower performanceStorage capacityIn RAID 0, the total storage capacity is equal to the sum of the storage capacity of all the disks in the RAID 0 array group. This means that if you have two disks in a RAID 0 array, with the size of 80GB for each disk, then the total storage capacity in the RAID 0 array available to store data is 160GB.Notice that RAID 0 can be created with disks of different sizes, but if the capacity for each disk in the RAID 0 array is different, then the total storage capacity available for that array equals to the number of available disk in the array multiplied by the smallest sized disk in that array. For example, if a 120 GB disk is striped together with a 100GB disk, the size of the array will be 200GB (Number of available disk * smallest size of the disks = 2 * 100GB).No fault-toleranceIf a failure occurs in any of the disks in an array, the entire array is destroyed which will result in data loss. This is due to the fact that the data is distributed in equally sized blocks to all the drives in the array, and therefore is no data redundancy or data backup on RAID 0, unless data backup is manually configured by the administrator.No error-checkingRAID 0 does not implement any error-checking so data error is unrecoverable.When RAID 0 is suitable?RAID 0 is recommended for deployment in an environment where data transfer is a priority but downtime because of disk failure is not a big issue. An example of a recommended application would be for video production or editing, multimedia applications, or all applications requiring high bandwidth.RAID 0 should NEVER be used in a mission critical environment, where fault-tolerance becomes a very important issue.
22 ✕ ✕ Illustration of RAID 0 RAID Technologies Data123456Primary Disk✕Disk-0Disk-1Disk 0Network Storage12✕34Disk 156If RAID 0 is in use and one of the disks in the array crashes, the rest of disks in the array will also not work. This will result is total data loss.Page is Animated
23 RAID 1 Technology Overview RAID TechnologiesRAID 1RAID 1 Technology OverviewCharacteristics of RAID 1RAID 1 works by mirroring the dataAt least two hard drives must be providedFault-toleranceAdvantages and disadvantagesAdvantagesDisadvantages100% data redundancyHighest disk overhead of all RAID typesInefficient because only 50% of the physical drive storage’s capacity is usedCharacteristics of RAID 1:Minimum of two hard drives or even number of disks must be provided in order to do data mirroring.Fault-toleranceRAID 1 provides fault-tolerance from disk errors and failures of any drives in the array.When RAID 1 is suitable?RAID 1 is recommended for environments which use applications that require high availability and immediate access to the disk is still possible if any disk failure occurs. Those applications are, such as, financial related applications (accounting, payroll, taxation, etc).
24 ✕ Illustration of RAID 1 RAID Technologies If RAID 1 is in use and the primary disk crashes, the mirrored disk will automatically replace the primary disk.Disk-0Disk-111✕2233Network StoragePrimary Disk44Mirrored Disk100% Redundancy!!!Page is Animated
25 RAID 5 Technology Overview RAID TechnologiesRAID 5RAID 5 Technology OverviewCharacteristics of RAID 5 technology:Striped set with distributed parityMinimum three disks must be provided to implement RAID 5Offers data protection and increases throughputAdvantages and DisadvantagesAdvantagesDisadvantages100% data protectionOffer more physical drive storage capacity than RAID 1Highest read data transaction rateDistributing the parity over all of the disks rather than putting all the parity on one diskExtra time needed to calculate the parityDisk failure has a medium impact on throughputDifficult to rebuild volume in the event of a disk failure (as compared to RAID level 1)Striped set with distributed parity. Distributed parity requires all drives but one to be present to operate. Drive failure requires replacement, but the array is not destroyed by a single drive failure. Upon drive failure, any subsequent reads can be calculated from the distributed parity such that the drive failure is masked from the end user. The array will have data loss in the event of a second drive failure and is vulnerable until the data that was on the failed drive is rebuilt onto a replacement drive.Parity is a calculated value that can be used to reconstruct data after a failure. While data is being written to a RAID-5 volume, parity is calculated by performing an exclusive OR (XOR) procedure on the data. The resulting parity is then written to the volume. If a portion of a RAID-5 volume fails, the data that was on that portion of the failed volume can be recreated from the remaining data and the parity.When RAID 5 is suitable?When users require acceptable tradeoffs between availability, capacity, data protection and performance when compared to other RAID configurations, RAID 5 is the best solution that provides those advantages. RAID 5 provides acceptable levels of data protection, disk utilization and performance for most applications.With RAID 5, users can enjoy high productivity when doing performance-demanding tasks and use it as a repository of precious artwork and digital assets.Recommended application for RAID 5 deployment are, for example, File and Application servers, Database servers, Web, , and News servers, Intranet servers.Mostly, the above applications require a balance of availability, capacity, data protection and performance.
26 Data is fully recovered!!! RAID TechnologiesRAID 5Illustration of RAID 5Data to be written:Using RAID 5, if one of the disks in the array fails, data in the failed disk can be recoveredData is fully recovered!!!Disk-2 fails, data cannot be accessed!!!✕New Disk to replace the failed diskDisk-0Disk-1Disk-21P=1 (1 XOR 0)1 XOR 0 = 11P=0 (1 XOR 1)11 XOR 0 = 1P=1 (1 XOR 0)11 XOR 1 = 0P=1 (0 XOR 1)1Each parity volume in the RAID 5 configuration is produced from the XOR calculation. XOR calculation compares two binary digits and calculates the result from the comparison. The result will be as follows from any given two bits:1 XOR 1 = 01 XOR 0 = 10 XOR 0 = 00 XOR 1 = 1In a RAID 5 implementation, bit per bit of data on one disk will be compared to each bit of data on the next available disk. The result, which is the parity data, will be written to the defined space in the other disk. The way RAID 5 writes the data is in the distributed/striped manner as illustrated above.From the above illustration, when any drive in an array fails, data in the failed drive can be rebuilt through the XOR calculation process.1 XOR 0 = 11P=1 (1 XOR 0)1 XOR 0 = 11P=1 (1 XOR 0)1 XOR 1 = 0Rebuilt process started!Data can be rebuilt to the new disk using XOR calculations by recalculating the two bits retrieved from the existing drivesP: parityPage is Animated
27 RAID 10 Technology Overview RAID TechnologiesRAID 10RAID 10 Technology OverviewCharacteristics of RAID 10 technology:RAID 10 provides mirroring and striping at the same timeMinimum four disks or even number of disks is requiredProvides fault-tolerance and improves performanceAdvantages and DisadvantagesAdvantagesDisadvantagesProvide fault tolerance to prevent data lossProvide high performance for I/O operation (read and write)Expensive, many disks are required to implement this RAID technologyOnly 50% of the physical drive storage’s capacity is used, if implements mirroring mechanismCharacteristics of RAID 10 technology:RAID 10: The volume is first mirrored, and then both mirrors are striped. This provides fault tolerance and improves performance but increases complexity. The key difference from RAID 0+1 is that RAID 10 creates a striped set from a series of mirrored drives. In a failed disk situation, RAID 10 performs better because all the remaining disks continue to be used. The array can sustain multiple drive losses so long as no mirror loses both its drives.When RAID 10 is suitable?RAID 10 is an excellent solution for sites that would have otherwise gone with RAID 1 but need some additional performance boost.This RAID type is highly recommended for applications that require high performance and fault tolerance.
28 Very high reliability combined with high performance!!! RAID TechnologiesRAID 10Illustration of RAID 10RAID 0 - Stripe5Disk-031Very high reliability combined with high performance!!!RAID 1 - MirrorDisk-16Disk-242Disk-3CharacteristicRAID 10 combines RAID 1 and RAID 0 together. Its implementation first mirrors the data from one disk to another disk, then it stripes the data to multiple disk drives in an array. RAID 10 mirrors data across half of the disk drives in an array (which is the first set of disk drives), while on the other half of the array, the data is then striped across the rest of the remaining disk drives in the RAID 10 configuration.Fault-ToleranceBy combining the features of RAID 0 and RAID 1, RAID 10 provides robust fault tolerance. Access to data is preserved if one disk in each mirrored pair remains available. Referring to the above diagram, for example, if Disk-0 fails, the group will still work properly and be able to respond to read/write requests from the client. The same condition applies if Disk-2 fails, but if Disk-1 or Disk-3 fails, the data will be lost and will be unrecoverable because there is no backup data left.PerformanceRAID 10 performance is similar to the performance of RAID 0 while providing disk redundancy and at higher performance if compared to RAID 1.
29 JBOD Technology Overview RAID TechnologiesJBODJBOD Technology OverviewCharacteristics of JBOD (Just a Bunch Of Disks):No Data redundancy, which means no fault-toleranceBigger array capacityTwo or more hard disks are required to create one logical driveAdvantages and DisadvantagesAdvantagesDisadvantagesProvide 100% storage capacity utilizationNo data redundancy or fault-tolerance providedAs the name implies, disks are merely concatenated together, end to beginning, so they appear to be a single large disk. This mode is sometimes called JBOD, or "Just a Bunch Of Disks". Concatenation may be thought of as the reverse of partitioning. While partitioning takes one physical drive and creates two or more logical drives, JBOD uses two or more physical drives to create one logical drive. As it consists of an array of independent disks, it can be thought of as a distant relation to RAID. Concatenation is sometimes used for turning several odd-sized drives into one larger useful drive, which cannot be done with RAID 0. For example, JBOD can combine 3 GB, 15 GB, 5.5 GB, and 12 GB drives into a logical drive at 35.5 GB, which is often more useful than the individual drives separately.
30 Logically seen as one big storage RAID TechnologiesJBODIllustration of JBODJBOD is usually known as concatenation where the total storage capacity equals to the sum of each separate disk.Logically seen as one big storageDisk-0Disk-1165267…Total storage capacity (Σ) =capacity of Disk-0 + capacity of Disk-1…….Note that JBOD is different with RAID 0 and it cannot be categorized under any RAID level. JBOD does not perform any data striping. It only enlarges the storage capacity by combining multiple physical drives with different storage capacity into one large virtual storage.JBOD will write data to the first disk drive in the JBOD group until the drive is out of space and then will continue to write the data to the next drive in the group, and so on.64
31 Summary for Each RAID Technology RAID TechnologiesSummary for Each RAID TypeSummary for Each RAID TechnologyRAID LevelData RedundancyRead PerformanceWrite PerformanceMin. Number of DrivesRAID-0NoSuperior2RAID-1YesVery HighHighRAID-5Good3RAID-104JBODD-Link Storage Area Network allows migration between RAID levels, but this is dependent on number of HDD drives available.The performance of each RAID level may vary depending on the hardware platform used.
32 Summary: RAID Technologies Redundant Array of Independent Disks (RAID) is a data storage mechanism that provides better performance and/or data reliability.D-Link network storage appliances support RAID 0, RAID 1, RAID 10, RAID 5, RAID 6 and JBOD to offer greater performance and reliability for D-Link users. Which types of RAID supported is dependent on the models.RAID 0 provides the best performance with the fastest data transfer speed by striping all the data to multiple disks.RAID 1 provides data redundancy by mirroring/duplicating the data from one disk to another disk.RAID 5 offers data protection and increases throughput by creating data parity and distributing it to all the provided disks.RAID 6 offers data protection and increases throughput by creating data parity and distributing it to all the provided disks. Same as RAID 5, but with 2 parity disks.RAID 10 combines both RAID 0 and RAID 1 at once, thus providing greater performance while also serving data redundancy to prevent single point of failure.Just a Bunch of Disks (JBOD) is not a type of RAID mechanism and does not provide data redundancy. It is used for achieving greater storage capacity among all the hard disks, which may come in different sized capacity.
33 Questions and Answers: RAID Technologies Which RAID level does not support fault-tolerance for the stored data?RAID 0RAID 1RAID 10RAID 5JBODWhich RAID technology supports the consolidation of all disks with different sizes thus enlarging the capacity of available storage spaces?A, EC
35 Storage EssentialsStorage EssentialsAfter this section, you should gain more knowledge of the following:Basic terminologies commonly used to explain storage technologyDifferent hard drive technologies and the characteristics of each
36 Basic Terminologies Storage Essentials Basic Terminologies and ConceptsBasic TerminologiesBlock – A sequence of bytes or bits in which data is stored and retrieved on disk and tape devices.Array – A set of physical disks grouped into one or more logical drives.Logical drive - A set of actual physical disks that are grouped together and behave as if it were a single drive as seen by the user.Volume – A set of blocks of storage that are organized and presented for use by the server.Logical Unit Number (LUN) – number assigned to a logical unit.It can be used to refer to an entire physical disk, or a subset of a larger physical disk or disk volume. The physical disk or disk volume could be an entire single disk drive, a partition (subset) of a single disk drive, or disk volume from a RAID controller comprising multiple disk drives aggregated together for larger capacity and redundancy. LUNs represent a logical abstraction between the physical disk device/volume and the applications. For example if you partition a disk drive into smaller pieces for your application or system needs (perhaps your server's operating system has a disk drive size limit) the sub-segments would share a common SCSI target ID address with each partition being a unique LUN.In an iSCSI environment, LUNs are essentially numbered disk drives. An initiator negotiates with a target to establish connectivity to a LUN; the result is an iSCSI session that emulates a SCSI hard disk. Initiators treat iSCSI LUNs the same way as if they were a raw SCSI or IDE hard drive. For instance, rather than mounting remote directories as will be done in NFS or CIFS environments, iSCSI systems format and directly manage file systems on iSCSI LUNs.In enterprise deployments, LUNs usually represent slices of large RAID disk arrays, often allocated one per client. iSCSI imposes no rules or restrictions on multiple computers sharing individual LUNs; shared access to a single underlying file system is instead left as a task for the operating system.
37 Spare Count Storage Essentials Definition of Spare Basic Terminologies and ConceptsSpare CountDefinition of SpareSpare is an drive (drive B) which is reserved for the purpose of substituting for another drive (drive A) in case of a failure on drive A.Definition of Hot SpareHot spare is a drive which has been flagged for use if another drive in the array failsDefinition of Spare CountSpare count is the number of drives to be kept available in case a drive which contains a volume (with data) fails.When one of the active drives fails, the hot spare drive will replace the failed driveActive DrivesHot Spare DriveSpare Count = 1Page is Animated
38 Hard Drive Interface Technologies Overview Storage EssentialsHard Drive Interface TechnologiesHard Drive Interface Technologies OverviewATA (Advanced Technology Attachment)Mostly used in desktops and notebooksConsist of two standards:PATA (Parallel ATA)SATA (Serial ATA)SCSISerial Attached SCSI (SAS)Fiber Channel*Hard disk drives are accessed over one of a number of bus types, including parallel ATA (PATA, which also called as IDE), Serial ATA (SATA), SCSI, Serial Attached SCSI (SAS), and Fiber Channel.At this point of time, the existing hard drive interfaces are SATA, SAS, SCSI, and Fiber Channel.SATA (Serial ATA) is a storage interface technology which introduces several key advantages, such as full bandwidth to each connected device, hot plug capability, smaller connector, standardized connector placement and layout, simpler cabling, and longer cable length. It transfer data by sending one bit of data at a time.SAS (Serial Attached SCSI) is a data transfer technology which replaces the parallel SCSI bus technology. Its key advantages are similar to SATA.SCSI is a hardware interface that allows for the connection of up to 15 peripheral devices to a single PCI board called a SCSI host adapter that plugs into the motherboard.Fiber Channel is a technology for transmitting data between computer devices at data rates of up to 4 Gbps, and 10 Gbps in the near future. It can be run on both copper cables and fiber optic media. It allows concurrent communications among workstations, mainframes, servers, data storage systems, and other peripherals using SCSI and IP Protocols.* Fiber channel is now commonly used for SAN solutions, but seldom used for end user computers. Though there are Fiber Channel hard drives available in the market, they are hardly found.* Fiber channel is now commonly used for SAN solutions, but seldom used for end user computers. Though there are Fiber Channel hard drives available in the market, they are hardly found these days.
39 Serial ATA Value Proposition Storage EssentialsHard Drive Interface TechnologiesWhy SATA?End-User NeedsMore storage in limited spaceImproved price/ performanceInvestment protectionLower overall system costSerial ATA Value PropositionNarrower CablingSupports lower power requirementsLower pin countsHigher performance (data rates up to 300MBps)Improved connectivity (no master/ slave)Longer cabling (reach up to one meter)System Vendor NeedsDense boxesSimilar componentsLower power consumptionIncreased air flowMore motherboard spaceHere are a few advantages to SATA over IDE:SATA cables are thinner and can be longer, thus effectively improving airflow and ease of handling/neatness/flexibility in the computer.SATA drives do NOT have jumper cables, meaning no fussing with Master/slave/cable select settings.SATA transfer rates are generally higher (provides faster speed)SATA handles RAID betterMOST important: SATA drives are supposedly Hot-pluggable (or Hot-swappable), meaning that you can plug-and-unplug them while computer is running. Most motherboards that support SATA provide you with external connectors (Power and Data) so, if need be, you can use a SATA drive on different computers just like any USB or other external drives (provided it is not the main drive that has the system installed, of course).Serial ATA offers more features and better performance than parallel ATAPage is Animated
40 Evolution of SATA Storage Essentials Hard Drive Interface TechnologiesEvolution of SATAThe Serial ATA (SATA) working group will deliver incremental specification releases over the next several years. These enhancements will enable the technology to support a variety of possible storage configurations.Serial ATA II, Phase 2Second-generation speed grade for desktops and network storage systems (Targeted 300 MB/sec)Improvements to address additional needs in higher-end network storage segmentsTopology support for dual host active failoverEfficient connectivity to larger number of devicesSerial ATA II, Phase 1Improved use of SATA 1.0 technology in server and network storageBackplane interconnect solution for racks of hot-swap drivesComplete enclosure management solution (Fan control, drive lights, temperature control, new device notifications, etc)Performance improvement to address industry needs (firmware/ software, performance enhancements, including native queuing)The Serial ATA provides some enhancements which will enable the technology to support a variety of possible storage configurations.Serial ATA 1.0Primary inside-the-box storage connection to replace parallel ATAPage is Animated
41 SCSI Technology Overview Storage EssentialsHard Drive Interface TechnologiesSCSI Technology OverviewSCSI (Small Computer System Interface) is a set of standards for physically connecting and transferring data between computers/ servers and peripheral devices.SCSI is commonly used for hard disks and tape drives, but can also be connected to a wide range of other devices, including scanners and CD drives.Characteristics of SCSI:Every device attaches to the SCSI bus in a similar manner.SCSI is a peripheral interface where up to 16 devices (the host adapter counts as one device) can be attached to a single bus (several peripherals can be daisy chained to one host adapter, using only one slot in the bus). There can be any number of hosts and peripheral devices but there should be at least one host.SCSI is a buffered interface: it uses hand shake signals between devices, SCSI-1, SCSI-2 have the option of parity error checking. Starting with SCSI-U160 (part of SCSI-3) all commands and data is error checked by a CRC32 checksum.SCSI is a peer to peer interface: the SCSI protocol defines communication from host to host, host to a peripheral device, peripheral device to a peripheral device. However most peripheral devices are exclusively SCSI targets, incapable of acting as SCSI initiators—unable to initiate SCSI transactions themselves. Therefore peripheral-to-peripheral communications are uncommon, but possible in most SCSI applications.
42 Summary: Storage Essentials Hot spares are standby hard disk drives which are used as a backup to automatically replace a disk when a failure occurs. Spare count is the number of the hard disk drives provided as backup disks.Currently, there are many hard drive technologies being provided in the market which evolves from time to time. The most well known technologies are SATA, SCSI, Serial Attached SCSI (SAS), and Fiber Channel.SATA is the most commonly used technology today, especially at the end user level, e.g. computer device.SCSI was commonly used for hard disks and tape drives, but can also be connected to a wide range of other devices, including scanners and CD drives. Currently, SCSI is widely used on servers and not on the end user client devices.
43 Questions and Answers: Storage Essentials What is the benefit of providing a spare disk?To enlarge the storage capacity when all disks have been used to store data.Ensure reliability by designating the spare disk as a standby/backup disk which will be used in case of disk failure.To serve as additional disk for use when scheduled downloading is configured.To serve as part of a RAID when configured, for example, to save mirrored data for RAID 1.Select the hard drive type(s) which offer the key advantages of full bandwidth to each connected device, hot plug capability, smaller connector, standardized connector placement and layout, simpler cabling, and longer cable length. (Choose all that apply)SCSISATAiSCSIPATAWhat are the benefits of using SATA hard disks when compared to IDE hard disks? (Choose all that apply)Master/Slave selectionSmaller cable connectorSpeedHot-pluggableBB, DB, C, D
45 SAN TechnologiesSAN TechnologiesAfter this section, you should gain more knowledge of the following:Technologies built for Storage Area NetworkDetails about FC SAN technologies and the required components to implement it on the networkDetails about iSCSI technologies as well as its advantages and the required components to implement iSCSI on SAN
46 SAN Technologies Overview Technologies lies behind the SANSAN Technologies OverviewTechnologies created for building a SAN are primarily based on either Fiber Channel or iSCSI technology.The next few pages explain each of these technologies in greater detail.iSCSI TargetiSCSI InitiatorD-Link SANTCP/IP ProtocolPrivateLocal NetworkSANCopper / Optical cabling for iSCSI connectionEthernet SwitchiSCSI Technology
47 Fiber Channel Technology Overview SAN TechnologiesFiber Channel TechnologyFiber Channel Technology OverviewFiber Channel (FC) is a channel/network standard defined by the Technical Committee T11, which is the committee within INCITS (InterNational Committee for Information Technology Standards) responsible for Fiber Channel InterfacesFC network contains network features that provide the required connectivity, distance, and protocol multiplexing.Advantages of Fiber Channel*:Solutions leadershipReliableFast data transfer providing gigabit bandwidth up to 4GbpsMultiple topologiesScalableCongestion freeHigh EfficiencyFull suite of services* The information is taken from Fiber Channel Industry Association (http://www/fibrechannel.org)Fiber Channel is a powerful, open ANSI standard, has a well-proven track record of economically meeting the challenge with these advantages, to name only a few:Solutions Leadership - Fiber Channel provides versatile connectivity with scalable performance with the strength of a mature, full market of suppliers With over 100 companies, including all of the top 20 server and storage suppliers, product choices ranging in the 1000ˆs, more than 80 million ports installed to date with an overall market annual revenues of more than a billion dollars [CHECK MATH ON EVERYTHING], you can rest assured that your Fiber Channel investment is preserved, safe and secure.Reliable - Fiber Channel, the most reliable form of storage communications, sustains an enterprise with assured information delivery. Reliability was designed into Fiber Channel standards and products right from the start.4 Gigabit Bandwidth Now - Gigabit solutions are becoming the norm today. On the horizon is 10 gigabit-per-second data delivery.Multiple Topologies - Fiber Channel supports the most protocols with the most published, open standards and released products for protocols such as SCSI, IP, ESCON, VI, and AV. Fiber Channel was designed to be totally transparent and autonomous to the protocol mapped over it. SCSI, TCP/IP, video, or raw data can all take advantage of high-performance, reliable Fiber Channel network.Scalable - From single point-to-point high-speed links to integrated enterprises with hundreds of servers, Fiber Channel delivers unmatched performance.Congestion Free - Fiber Channel's credit-based flow control delivers data as fast as the destination buffer is able to receive it, without dropping frames or losing data and without the need for upper-layer retries This is one of the exclusive features of Fiber Channel that make it so well suited for block-level storage data networks and interconnects.High Efficiency – Fiber Channel has very little transmission overhead. Most important, the Fiber Channel protocol is specifically designed for highly efficient operation using hardware for protocol offload engines (POE's). Fiber Channel products and installations have long used highly integrated POE's as necessitated by the high-end, high-performance demands of the markets that were early to adopt Fiber Channel, first as an interconnect, then as the key enabling factor to the advent of Storage Area Networking. Fiber Channel simply, and easily, provides the best bang for the buck!Full Suite of Services - Fiber Channel surpasses all interconnects when it comes to already-released standards and products that are required to build a SAN; inside and out. Fiber Channel pioneered and established throughout the market a mature set of storage network services such as discovery, addressing, LUN zoning, fail-over, management, and security.
48 Basic Components of Fiber Channel SAN SAN TechnologiesFiber Channel TechnologyBasic Components of Fiber Channel SANStorage devices supporting Fiber ChannelFiber Channel Switch (SAN fabric)Fiber Channel Host Bus Adapter (HBA)CablingPrivateFiber ChannelSANPublic LocalArea NetworkFC Host Bus AdapterFC Storage MediaOptical cabling for fiber channel connectionFiber Channel SwitchBasic hardware components of Fiber Channel SAN are comprised of several physical components as in the following:Storage devices which support Fiber ChannelFiber channel switch to form a SAN fabricFiber Channel switch provides any-to-any connectivity for servers and storage devices. Two or more interconnected switches will create a SAN fabric. SAN fabric allows to improve the SAN performance while also optimizing the scalability and availability.Fiber Channel Host Bus Adapter (HBA)HBAs are used to connect each host to the FC SAN. Host Bus Adapters consists of hardware and drivers. It is intelligent, providing negotiation with switches and devices attached to the network. It also provides processing capabilities that minimize CPU overhead on the host.Cabling – Copper and Fiber Optic cables are two types of cables used in SANs.
49 iSCSI Technology Overview SAN TechnologiesHard Drive Interface TechnologiesiSCSI Technology OverviewDefinition of iSCSI (Internet SCSI)SCSI protocol which enables access to networked storage devices over a TCP/IP network (Ethernet network, WAN, Wireless network, etc)Why iSCSI? – iSCSI FeaturesError HandlingError checking using CRC (Cyclic Redundancy Check) methodologyWhen iSCSI detects errors it will bring down the session (all TCP connections within the session) and restart itBootDiscoveryAdvantages of iSCSIConnectivity over long distancesLower costsEasier implementation and managementBuilt-in securityiSCSI is Internet SCSI (Small Computer System Interface), an Internet Protocol (IP)-based storage networking standard for linking data storage facilities, developed by the Internet Engineering Task Force (IETF). By carrying SCSI commands over IP networks, iSCSI is used to facilitate data transfers over intranets and to manage storage over long distances.Advantages of iSCSI:Connectivity over long distances.iSCSI offers wide area network coverage providing a cost-effective long distance connection that can be used as a bridge to existing Fiber Channel SANs thus centralizing the administration of storage systems.Lower costsiSCSI SAN solutions capitalize on the preexisting LAN infrastructure and make use of the much more ubiquitous IP expertise available in most organizations.Simpler implementation and managementManaging iSCSI devices for such operations as storage configuration, provisioning, and backup can be handled by the administrator in the same way that such operations for direct attached storage are handled.Built-in securityCurrently, iSCSI implements CHAP to guarantee secure access to the storage system.
50 Advantages of iSCSI over FC SAN SAN TechnologiesHard Drive Interface TechnologiesAdvantages of iSCSI over FC SANiSCSI is a better alternative to Fiber Channel SAN for the following reasons:Built on stable and familiar standards providing easier implementation and managementEthernet transmissions can travel over the global IP network and therefore have no practical distance limitationScalableCreates a SAN with lower costInteroperability issueSecurity issueSource : IDC 2006 Sept./Dec.Advantages of iSCSI over Fiber Channel SAN are as the following:Simpler implementation and managementiSCSI solutions require little more than the installation of the Microsoft iSCSI initiator on the client server, a target iSCSI storage device, and a Gigabit Ethernet switch in order to deliver block storage over IP. Managing iSCSI devices for such operations as storage configuration, provisioning, and backup can be handled by the system administrator in the same way that such operations for direct attached storage are handled. Solutions, such as clustering, are actually simpler with iSCSI than with Fiber Channel configurations.No practical distance limitation even for MAN or WAN environmentSANs have delivered on the promise to centralize storage resources—at least for organizations with resources that are limited to a metropolitan area. Organizations with divisions distributed over wide areas have a series of unlinked “SAN islands” that the current Fiber Channel (FC) connectivity limitation of 10 km cannot bridge. There are new means of extending Fiber Channel connectivity up to several hundred kilometers but these methods are both complex and costly. iSCSI over wide area networks (WANs) provides a cost-effective long distance connection that can be used as a bridge to existing Fiber Channel SANs (FC SANs)—or between native iSCSI SANs—using in-place metropolitan area networks (MANs) and WANs.Lower CostUnlike an FC SAN solution, which requires the deployment of a completely new network infrastructure and usually requires specialized technical expertise and specialized hardware for troubleshooting, iSCSI SAN solutions capitalize on the preexisting LAN infrastructure and make use of the much more ubiquitous IP expertise available in most organizations.Interoperability issue with Fiber Channel SAN.While Fiber Channel storage networks currently have the advantage of high throughput, interoperability among multi-vendor components remains a shortcoming. iSCSI networks, which are based on the mature TCP/IP technology, are not only free of interoperability barriers but also offer built-in gains such as security. And, as Gigabit Ethernet is increasingly deployed, throughput using iSCSI is expected to increase, rivaling or even surpassing that of Fiber Channel.Security issue with Fiber Channel SANNo security measures are built into the Fiber Channel protocol. Instead, security is implemented primarily through limiting physical access to the SAN. While this is effective for SANs that are restricted to locked data centers (where the wire cannot be “sniffed” as the hardware design makes this difficult. To sniff the wire, a special analyzer will have to be inserted between the host bus adapter and the storage), as the FC protocol becomes more widely known and SANs begin to connect to the IP network, such security methods lose their efficacy.In contrast to Fiber Channel, the implementation of the iSCSI protocol provides security for devices on the network by using the Challenge Handshake Authentication Protocol (CHAP) for authentication.According to IDC, iSCSI market grows with an explosive record of about 108.4% every year. According to IDC, by 2010, iSCSI products will share more than 21% of the storage market.
51 iSCSI SAN Overview SAN Technologies iSCSI SAN components consist of: Drive Interface TechnologiesiSCSI SAN OverviewiSCSI SAN components consist of:iSCSI Client/ Host (iSCSI initiator)A client device, for example, a server (or PC), which attaches to an IP networkiSCSI Client initiates requests and receives responses from an iSCSI targetiSCSI TargetA device that receives and processed the iSCSI commands, for example, a storage deviceServeriSCSI InitiatorTCP/IP ProtocoliSCSI solutions require little more than the installation of the Microsoft iSCSI initiator on the client server, a target iSCSI storage device, and a Gigabit Ethernet switch in order to deliver block storage over IP.iSCSI SAN components are largely analogous to FC SAN components. These components are as follows:iSCSI Client/HostThe iSCSI client or host (also known as the iSCSI initiator) is a system, such as a server (or PC), which attaches to an IP network and initiates requests and receives responses from an iSCSI target. Each iSCSI host is identified by a unique iSCSI qualified name (IQN).To transport block-level (SCSI) commands over the IP network, an iSCSI host must either attach an iSCSI Host Bus Adapter (HBA) or install an iSCSI driver, for example the Microsoft iSCSI initiator.To get the latest iSCSI initiator from Microsoft, please check on the following URL: . Or check and download it from the Microsoft Download Center for the latest iSCSI initiator driver.A Gigabit Ethernet adapter (transmitting 1000 Megabits per second--Mbps) is recommended for connecting to the iSCSI target. Like the standard 10/100 adapters, most Gigabit adapters use Category 5 or Category 6E cabling that is already in place. Each port on the adapter is identified by a unique IP address.iSCSI TargetAn iSCSI target is any device that receives iSCSI commands. The device can be an end node, such as a storage device, or it can be an intermediate device, such as a bridge between IP and Fiber Channel devices.Each iSCSI target is identified by a unique IQN, and each Ethernet port on the storage array (or on a bridge) is identified by one or more IP addresses.iSCSI TargetD-Link SAN
52 Summary: SAN Technologies iSCSI is a network protocol which enables access to storage devices and network storage over TCP/IP networks.D-Link adopts the iSCSI protocol to be used in its D-Link SAN.iSCSI offers several benefits in comparison to Fiber Channel. These include interoperability, scalability, security, cost, and distance limitation.To implement iSCSI on the SAN, all the components must be provided: iSCSI initiator, iSCSI target, and Ethernet switch.
53 Questions and Answers: SAN Technologies What are the components needed when deploying Fiber Channel SAN? (Choose all that apply)SCSI StorageSwitchFiber Channel SwitchFC Host Bus AdapterWhat component s not needed when deploying iSCSI?ServeriSCSI targetC, DD
55 D-Link SAN (Storage Area Network) After this section, you should gain more knowledge of the following:Various D-Link SAN appliances and differences between eachEach part of the hardware in the SANKey selling points of D-Link SAN appliancesProduct positioning of D-Link SANsD-Link SAN product interoperability, caching behavior, and common implementation architectures
56 D-Link Storage Area Network D-Link SAND-Link Products for Storage Area NetworkD-Link Storage Area NetworkDSN-2100 SeriesDSNDSN-3200 SeriesDSNDSNDSN-3400 SeriesDSNDSNxStack Storage with 4-port 1GE Copper for SATA-II Hard Drives in RAID Levels 0, 1, 1+0, and 5 (8 Trays)xStack Storage with 8-port 1GE Copper for SATA-II Hard Drives in RAID Levels 0, 1, 1+0, and 5 (15 Trays)xStack Storage with 1-port 10 GE Fiber for SATA-II Hard Drives in RAID Levels 0, 1, 1+0, and 5 (15 Trays)
57 Components of D-Link DSN-2100 Series D-Link SANComponents of D-Link SANComponents of D-Link DSN-2100 SeriesFront Panel ComponentsFront panel after the bezel has been removedKey lockEight drive baysPower LEDBoot and Fault LEDLatchRemovable BezelDrive power LEDDrive and Activity Fault LEDBack Panel ComponentsThe xStack Storage unit back panel also has a 10/100 Mbps management port and an RS-232-C DB9 diagnostic/console port.The admin account cannot be deleted in firmware version and above. For security, please be sure to change the password for this account. However, if you lose the password for the admin account, you may use the diagnostic port to reset the password.Diagnostic PortPower SwitchHost network connectionsPower SupplyManagement PortReset Switch
58 Components of D-Link DSN-3200 Series D-Link SANComponents of D-Link SANComponents of D-Link DSN-3200 SeriesFront Panel ComponentsRemovable BezelKey lockBack Panel ComponentsPower SupplyPower SwitchReset SwitchThe xStack Storage unit back panel also has a 10/100 Mbps management port and an RS-232-C DB9 diagnostic/console port.Host Network ConnectionsDiagnostic PortManagement Port
59 Components of D-Link DSN-3400 Series D-Link SANComponents of D-Link SANComponents of D-Link DSN-3400 SeriesFront Panel ComponentsRemovable BezelKey lockBack Panel ComponentsPower SupplyPower SwitchReset SwitchThe xStack Storage unit back panel also has a 10/100 Mbps management port and an RS-232-C DB9 diagnostic/console port.The main difference between the DSN-3400 series as compared to the other DSN series (DSN-2100 series and DSN-3200 series) is from its type of host network connection provided. The DSN-3400 series provides one 10-Gigabit Ethernet with XFP transceiver interface, while others provides four or eight Gigabit Ethernet connections with RJ-45 interfaces.Note that the XFP transceiver used to connect to the DSN-3400 series is sold separately.Host Network ConnectionsDiagnostic PortManagement Port
60 Management Port and Diagnostic Port D-Link SANComponents of D-Link SANManagement Port and Diagnostic PortManagement PortThe management port is used to configure and manage D-Link’s xStack SAN from the PC, either directly connected to the SAN (using a Crossover cable) or connected to the SAN through the use of a hub or switch (using Straight-through cable).By connecting to this management port, the administrator can configure the D-Link SAN through the web GUI.Diagnostic PortThe diagnostic port is a console port which uses a RS-232-to-DB-9 port interface. This port can be used if you have direct physical access to the box and is accessed during startup.The diagnostic port performs all admin password resets, sets the download configuration parameters, and accesses the Enclosure Services Test Tool.xStack Storage provides out-of-band management capabilities, which means that management and data traffic are on separate lines. Therefore, the administrator cannot connect the same NIC to the management and host network connection ports. Instead, one NIC must connect to the management port and a different NIC, either in the same PC or a different PC, must connect to the host network connection port. Communication via the management port is encrypted using SSL, without requiring configuration by the user.
61 DSN-2100 Series D-Link SAN D-Link DSN-2100 Series Volume and RAID supportSingle RAID Controller (Integrated in ASIC)RAID support (Level 0, 1, 1+0, 5)Supports 1,024 Virtual Volumes (256 accessible per initiator)1,024 target nodesOnline capacity expansionHot swappable drivesInstant volume accessFree space defragmentationAuto-detection failed driveAuto-rebuild spare driveRAID level migrationDrive roaming-in power offSelf-Monitoring Analysis and Reporting Technology (S.M.A.R.T)Hardware SpecificationDrive Bays: 8Drive Interface support: SATA-IIStorage Capacity: 8TB capacity with 1TB hard driveSystem Memory: 256MB to 512MB (512MB standard)Cache Memory: 256MB to 4Gb (512MB standard)iSCSI Network Interface: four (4) 1GbE portsiSCSI Network InterfaceHost Interface: iSCSI Draft 2.0 compliant initiatorConnections: 1,024 HostsJumbo Frames supportLink Aggregation supportCHAP authenticationAccess control of managementiSCSI/TCP/IP Full HW OffloadVLAN Support (Up to 8 VLANs)Storage ManagementEmbedded IP-based Management GUISMI-S version 1.1
62 DSN-3200 Series D-Link SAN D-Link DSN-3200 Series Hardware SpecificationDrive Bays: 15Drive Interface support: SATA-IIStorage Capacity: 15 TB capacity with 1TB hard driveSystem Memory: 512MBCache Memory: 4GBiSCSI Network Interface: eight (8) 1GbE portsVolume and RAID supportSingle RAID Controller (Integrated in ASIC)RAID support (Level 0, 1, 1+0, 5)Supports 1,024 Virtual Volumes (256 accessible per initiator)1,024 target nodesOnline capacity expansionHot swappable drivesInstant volume accessFree space defragmentationAuto-detection failed driveAuto-rebuild spare driveRAID level migrationDrive roaming-in power offSelf-Monitoring Analysis and Reporting Technology (S.M.A.R.T)iSCSI Network InterfaceHost Interface: iSCSI Draft 2.0 compliant initiatorConnections: 1,024 HostsJumbo Frames supportLink Aggregation supportCHAP authenticationAccess control of managementiSCSI/TCP/IP Full HW OffloadVLAN Support (Up to 8 VLANs)QoS support (IETF DiffServ and IEEE 802.1P tag)Storage ManagementEmbedded IP-based Management GUISMI-S version 1.1
63 DSN-3400 Series D-Link SAN D-Link DSN-3400 Series Volume and RAID supportSingle RAID Controller (Integrated in ASIC)RAID support (Level 0, 1, 1+0, 5)Supports 1,024 Virtual Volumes (256 accessible per initiator)1,024 target nodesOnline capacity expansionHot swappable drivesInstant volume accessFree space defragmentationAuto-detection failed driveAuto-rebuild spare driveRAID level migrationDrive roaming-in power offSelf-Monitoring Analysis and Reporting Technology (S.M.A.R.T)Hardware SpecificationDrive Bays: 15Drive Interface support: SATA-IIStorage Capacity: 15 TB capacity with 1TB hard driveSystem Memory: 512 MBCache Memory: 4GBiSCSI Network Interface: one (1) 10GbE portsiSCSI Network InterfaceHost Interface: iSCSI Draft 2.0 compliant initiatorConnections: 1,024 HostsJumbo Frames supportCHAP authenticationAccess control of managementiSCSI/TCP/IP Full HW OffloadVLAN Support (Up to 8 VLANs)QoS support (IETF DiffServ and IEEE 802.1P tag)Storage ManagementEmbedded IP-based Management GUISMI-S version 1.163
64 Key Selling Points of D-Link SAN Market Analysis for D-Link SAN ProductsKey Selling Points of D-Link SANBlock data transfer over TCP/IP network using iSCSIHighly integrated single chip solutionBuilt-in RAID controllerBuilt-in IP-SAN Device Manager (IDM)SATA-II support for the hard drive interfaceVarious number of iSCSI interfaces which can be aggregatedJumbo Frame support increases performance up to 20-50%** Based on information from Storage Networking Industry AssociationSeveral key selling points for D-Link’s Storage Area Network:Highly integrated single chip solution which allows the system to handle speeds of over 65,000 inputs/ outputs (I/O) per second.Built-in RAID Controllers provided (RAID 0, RAID 1, RAID 1+0, RAID 5, JBOD)Built-in IP-SAN Device Manager (IDM) which can be accessed from the WebSATA-II supportFour (DSN-2100) and Eight (DSN-3200) 1GbE iSCSI network interfaces which can be aggregated using LAG (Link Aggregation) feature to provide higher throughput.
65 Product Positioning for D-Link SAN Market Analysis for D-Link SAN ProductsProduct Positioning for D-Link SANThe D-Link xStack Storage product family of iSCSI SAN solutions are designed to address the growing high performance storage requirements brought about by the need for better application and database performance, infrastructure consolidation, and robust backup and disaster recovery solutions.D-Link now aggressively addresses these storage requirements at the SMB and enterprise level users by leveraging existing iSCSI and Ethernet technologies and lowering the total cost of ownership for storage area networking solutions over more complex legacy Fiber Channel and slower Network Attached Storage (NAS) solutions.DSN-2100/ DSN-3200 comes with Gigabit Copper interfaces and is mainly targeted at SMB users.DSN-3400 comes with 10-Gigabit Ethernet interfaces* and is mainly targeted for enterprise users.* DSN-3400 provides one 10GbE XFP transceiver interface (transceiver sold separately) accessed via the back panel.
66 Storage Interoperability – SMI-S Storage Device D-Link SAND-Link SAN ImplementationStorage Interoperability – SMI-S Storage DeviceStorage Management Initiative – Specification (SMI-S) is a storage standard developed and maintained by Storage Networking Industry Association (SNIA).The main objective of SMI-S is to guarantee interoperability of storage devices among different vendors.D-Link’s SAN series are all designed based on the standard SMI-S version 1.1.Basic conceptsSMI-S defines DMTF management profiles for storage systems. The complete SMI Specification is categorized in profiles and sub-profiles. A profile describes the behavioral aspects of an autonomous, self-contained management domain. SMI-S includes profiles for Arrays, Switches, Storage Virtualization, Volume Management and many other domains. In DMTF parlance, a provider is an implementation for a specific profile. A sub-profile describes part of the domain, which can be common part in many profiles.At a very basic level, SMI-S entities are divided into two categories:Clients are management software applications that can reside virtually anywhere within a network provided they have a physical link (either within the data path or outside the data path) to providers.Servers are the devices under management within the storage fabric.Clients can be host-based management applications (e.g., storage resource management, or SRM), enterprise management applications, or SAN appliance-based management applications (e.g., virtualization engines). Servers can be disk arrays, host bus adapters, switches, tape drives, etc.
67 D-Link SAND-Link SAN ImplementationCaching OperationThe xStack storage unit contains cache memory for storing and data.The xStack storage unit is capable of caching write operations. Write-back caching saves the system from performing many unnecessary write cycles to the system RAM, so as to provide faster execution.The xStack Storage unit is capable of caching write operations. Write-back caching saves the system from performing many unnecessary write cycles to the system RAM, which can lead to noticeably faster execution. However, when write-back caching is used, writes to cached memory locations are only placed in cache and the data is not written to the disks until the cache is flushed. When caching is disabled, all read and write operations directly access the physical disks. By default, write-back cache mode is always enabled and cannot be disabled.
68 Basic iSCSI SAN Implementation D-Link SAND-Link SAN ImplementationBasic iSCSI SAN ImplementationIn the most basic iSCSI SAN deployment, application servers (iSCSI hosts) access their storage from an iSCSI target storage array.iSCSI HostiSCSI Target……Private LANPublic LANIn the above scenario, clients on the public LAN attach to each server through a network adapter (previously referred to as a network interface card, or NIC). A second Gigabit adapter in each server provides access to a private iSCSI SAN connecting to the iSCSI target storage array through an Ethernet switch.The above architecture is also known as Native SAN architecture/ Implementation.The following are minimal hardware recommendations for all iSCSI deployments:Dual processors in all iSCSI hosts.Two iSCSI network adapters or iSCSI HBA host adapters:One standard 10/100 network adapter (previously known as a network interface card or NIC) for connection to the public LANOne Gigabit Ethernet network adapter for connecting to the target storage array. (Gigabit adapters transmit data at 1000 Mbps and, like standard adapters, connect to Category 5 cabling.)Isolation of the target storage array onto a private network.At a minimum, use of CHAP authentication between iSCSI host and target.
69 D-Link SANSummarySummary: D-Link SAND-Link provides three series for its SAN appliance product line which include DSN-2100, DSN-3200, and DSN-3400 series.D-Link DSN-2100 provides eight drive bays while D-Link DSN-3000 series provides 15 drive bays.Generally, all D-Link SANs must have the following components built in: host network connections, management port, diagnostic port, power and reset switch button, power supply, and removable bezel.D-Link SAN appliances are mainly targeted for SMB and enterprise level users who need better application and database performance, infrastructure consolidation, robust backup and disaster recovery solutions.D-Link SAN series is guaranteed to be interoperable with other storage appliances from different vendors because of its achievement for SMI-S standard.By default, all D-Link SANs will cache all write operations to prevent the storage from performing many unnecessary write cycles to the system RAM.
70 Questions and Answers: D-Link SAN What standard is used to guarantee the interoperability of storage devices among different vendors?IEEEiSCSISNIASMI-SWhich of the following statement describe D-Link SAN?D-Link SAN supports PAP authentication to provide secure access to the SAN.With D-Link SAN, using diskless server is possible because it can be booted form the iSCSI SAN.D-Link xStack storage cache memory for storing data and writing operations.DC
71 SAN Product Features Overview* * All features are explained based on DSN-3000 Series.
72 SAN Product Features Overview After this section, you should gain more knowledge of the following:Tasks/activities that can be done by D-Link SANLink aggregation and VLAN features supported in D-Link SANTCP/IP offload engineCHAP authenticationVolume virtualizationAuto-Detection failed drive and volume rebuild features
73 SAN Product Features Overview Volume ManagementTaskThe xStack Storage unit can automatically, or at the administrator’s demand, perform activities that take time and consume the controller’s resources.The administrator can control, to some degree, when tasks are to be performed. Any task can be suspended and resumed by the administrator. Some tasks can be cancelled and some can be scheduled on a recurring, periodic interval.All tasks can have their priority changed, which controls the amount of resources the xStack storage unit devotes to a task.The tasks/ activities that can be done by D-Link’s SAN are as follows:Volume initializationVolume rebuild*Volume expansionMedia scanningParity scanning* Volume rebuild will be explained later along with explanation of auto-detecting failed driveThe xStack storage unit can perform the following tasks:Initialize a volume: some volume organizations (e.g., parity) require initialization. The initialization task performs this action. This task can be performed while an initiator is accessing (reading and writing) data. An initialization task can be suspended and resumed, but cannot be cancelled.Rebuild a volume: when a drive fails, every redundant volume that occupies space on that drive can be rebuilt.For mirror protection, data can be copied from the remaining copy.For parity protection, data can be recreated from the remaining data and parity information.In either case, when the xStack Storage unit finds replacement space on another drive, it performs one rebuild task for each extent that used space on the failed drive. If replacement space is not available on the drives in the pool associated with the volume, and one or more drives exist in the available pool, a drive is obtained from the available pool and automatically moved to the volume's pool. A rebuild task can be suspended and resumed but cannot be cancelled.Expand volume: the administrator can expand the size of a volume. If the volume's organization requires initialization, the initialization of the new space is performed with a grow task. A grow task can be suspended and resumed, but cannot be deleted. An initiator can access the new space while the grow task is being performed.Media scan: the administrator can scan a non-parity volume for media errors by starting a media scan task. This task reads every block in the volume to ensure there are no errors. If there are errors, this task fixes them if possible. A media scan task can be cancelled, suspended and/or resumed by the administrator. It can also be scheduled for a future time and/or at a recurring interval.Parity Scan: The Administrator can scan a parity volume for errors by starting a Parity Scan task. This task reads every block in the volume looking for errors as described for Media Scan to ensure that parity is correct. If parity errors are found, this task corrects the errors. A parity scan task can be cancelled, suspended, and/or resumed by the Administrator. It can also be scheduled for a future time and/or at a recurring interval.
74 Volume Initialization SAN Product Features OverviewVolume ManagementVolume InitializationSome volume organizations (e.g. parity) require initialization. The initialization task performs this action. This task can be performed while an initiator is accessing (reading and writing) data. An initialization task can be suspended and resumed, but cannot be cancelled.Initialization task consists of:Making the volume XOR consistentDetecting a read errorRecovering from read errorSome volume organizations (e.g. parity) require initialization. The initialization task performs this action. This task can be performed while an initiator is accessing (reading and writing) data. An initialization task can be suspended and resumed, but cannot be cancelled.Initialization task consists of:Making the volume XOR consistentDetecting a read error caused by a read operation caused by a read operation on the storage wherein the read error is detected during the making of the storage volume XOR consistent.Recovering from the read error during the process of making the volume XOR consistent without terminating the step of making the volume XOR consistent.
75 The Volume-1 has been resized to a bigger size SAN Product Features OverviewVolume ManagementVolume ExpansionAll D-Link SAN product series provide volume expansion to flexibly resize a logical drive.The Volume-1 has been resized to a bigger size100GB300GB200GBCurrent size: 200GBThe administrator can expand the size of a volume. If the volume's organization requires initialization, the initialization of the new space is performed with a grow task. A grow task can be suspended and resumed, but cannot be deleted. An initiator can access the new space while the grow task is being performed.Expand to 300GBVolume-1Page is Animated
76 Parity Scanning SAN Product Features Overview Volume ManagementParity ScanningD-Link SAN provides parity volume scanning to check errors found in that selected volume.This task reads every block in the volume to ensure parity is correct. If parity errors are found, this task corrects the errors.The Administrator can scan a parity volume for errors by starting a Parity Scan task. This task reads every block in the volume looking for errors as described to ensure that parity is correct. If parity errors are found, this task corrects the errors. A parity scan task can be cancelled, suspended, and/or resumed by the Administrator. It can also be scheduled for a future time and/or at a recurring interval.
77 Storage Volume Information SAN Product Features OverviewVolume ManagementStorage Volume InformationStorage volume information provides comprehensive information about the storage volume allocationInformation that can be viewed in the storage volume information are:Status of the attached drives (offline or online)Volume CapacityVolume type
78 Event Log SAN Product Features Overview Device ManagementEvent LogThe event log tracks the xStack Storage’s information, warning, and error messages.
79 Link Aggregation SAN Product Features Overview iSCSI FeaturesLink AggregationDefinition of Link Aggregation:Link aggregation is a way to achieve double data rates by aggregating multi physical links as one logical link.Key benefits of Link Aggregation (LAG):Improved performanceHigh data ratesIncreased availabilityLoad sharingKey benefits of Link Aggregation (LAG):Combining multiple interfaces into one logical link improves performance because the capacity of an aggregated link is higher than individual link.Link aggregation provides high data rates.If failure occurs to a link with an LAG, the traffic will not be disrupted though the available bandwidth is reduced.With link aggregation, traffics are distributed across multiple links, minimizing the probability that a single link will be overwhelmed.
80 SAN Product Features Overview iSCSI FeaturesVirtual LAN (VLAN)All D-Link Storage Area Networks support 802.1Q VLAN tagging to segregate traffic into isolated zone for more secure access and to segment the broadcast domain.D-Link SAN supports up to eight VLANs with 1-to-1 mapping between IP subnet and VLAN. Multiple VLANs per physical port with VLAN tag. All physical ports in LAG belong to same VLAN.With this feature, a volume can be configured under a VLAN group so that it will only be accessible by clients under the same VLAN.All D-Link SAN series support IEEE 802.1Q VLAN tagging to segregate traffic into isolated zones for secure access. All xStack Storage models support eight VLANs, one for each IP address.When you create LAGs, you can also indicate whether the LAG is to support a virtual LAN (VLAN).
81 TCP/IP Offload Engine (TOE) SAN Product Features OverviewiSCSI FeaturesTCP/IP Offload Engine (TOE)The major issue of IP storage is the high TCP/IP processing overhead, which constrains servers to performance levels that are unacceptable for block storage transport.TCP/IP Offload is used for reducing the amount of TCP/IP processing handled by the microprocessor and I/O subsystem to help ease server networking bottleneck.The major issue of IP storage is the high TCP/IP processing overhead, which can constrain servers to performance levels that are unacceptable for block storage transport. Only TCP/IP offload technology can provide this level of performance. iSCSI is a good example of using TCP/IP offload to achieve high-performance IP storage.TCP/IP offload Engine (TOE) is one of the technologies that can reduce the amount of TCP/IP processing handled by microprocessor and server I/O subsystem, and thus ease server networking bottleneck. Deployment of TCP/IP offload in conjunction with high-speed Ethernet technologies enables applications to take full advantage of the networking capabilities.Network performance improvements gained from TOE technology can be determined by measuring either the increase in absolute network throughput or the reduction in system resources such as CPU utilization. TOE performance benefits vary with the type of applications being run. Applications with a small network packet size may experience gains in network throughput, while applications with a large network packet size may not show significant network throughput improvements with TOE but may experience a significant reduction in CPU utilization—thereby helping to keep CPU processing cycles available for other business-critical applications such as database, backup storage, media streaming, and file server applications. Applications that require extensive network utilization—such as network backups, network attached storage, file servers, and media streaming—typically benefit the most from TOE technology.
82 SAN Product Features Overview iSCSI FeaturesCHAP AuthenticationChallenge Handshake Authentication Protocol (CHAP) is a protocol for authenticating peer-to-peer connection based on the sharing of a ‘secret’ known only to the authenticator and that peer.CHAP authentication is supported in all D-Link SAN product series and is used when an initiator tries to connect to its target, and vice versa.Characteristics of CHAP authentication:Unidirectional/ Bidirectional authenticationSecret key is encrypted/ hashed using MD5 algorithmThree way handshake authenticationCharacteristics of CHAP authentication in D-Link SAN:Unidirectional/ Bidirectional AuthenticationUnidirectional or One-way CHAP authentication. With this level of security, only the target authenticates the initiator. The secret is set just for the target and all initiators that want to access that target need to use the same secret to start a logon session with the target.Bidirectional or Mutual CHAP authentication. With this level of security, both the initiator and the target needs to create a secret key itself for authenticating each other. In CHAP implementation, the target node (called party) must authenticate the initiator (calling party) and the initiator can also verify the identity of the target node. This results in a two-way authentication, thus providing a more secure environment.CHAP authentication provides three-way handshake authentication where the called party will send a challenge packet to the calling party where the packet is secret key which already hashed using MD5 algorithm. To pass the authentication, the calling party must response back to the called party with the correct answer.To use Challenge Handshake Authentication Protocol (CHAP) authentication, when connecting to an iSCSI target, type the password that will be used during mutual CHAP authentication when an initiator authenticates a target.
83 Volume Virtualization SAN Product Features OverviewVolume and RAID SupportVolume VirtualizationD-Link xStack storage virtualizes disk storage for use by a customer's host computer (servers).Storage virtualization is the process of grouping together independent storage devices found across a network to create what seems to be a single large storage entity that can be centrally managed.Storage virtualization helps make the tasks of backup, archiving, and recovery easier, and in lesser time, by disguising the actual complexity of the SAN.Benefits of virtualization:High availabilityImprove capacity utilizationShare resources between heterogeneous serversStorage virtualization is the process of grouping together independent storage devices found across a network to create what seems to be a single large storage entity that can be centrally managed.Benefits of virtualization:High availabilityImprove capacity utilization. Pooling storageResource sharing between heterogeneous servers (different platform of operating systems, e.g. Windows OS vs Linux OS). A virtualization in a SAN ensures that servers running different operating systems can safely stored on the same SAN.
84 Auto-Detection of Failed Drive & Volume Rebuild SAN Product Features OverviewVolume and RAID SupportAuto-Detection of Failed Drive & Volume RebuildWhen a drive in the storage array fails, the xStack storage will automatically detect the failed drive and substitutes it with the hot spare drive.A spare drive is normally kept in the available pool, so that the drive will be available for use should another drive fails.Volume rebuild is the activity that recovers data of a failed drive.In this case, data can be rebuilt if the storage system is mirrored (RAID 1) or set for parity (RAID 5).If the storage is mirrored, data will be recovered from the mirrored data in the mirror disk.If parity is created, data inside the failed drive will be recovered using the existing data from active disks and the parity information.When a drive fails, every redundant volume that occupied space on that drive can be rebuilt.For mirror protection, data can be copied from the remaining copy.For parity protection, data can be recreated from the remaining data and parity information.In either case, when the xStack Storage unit finds replacement space on another drive, it performs a rebuild task for each extent that used space on the failed drive. If replacement space is not available on the drives in the pool associated with the volume, and one or more drives exist in the available pool, a drive is obtained from the available pool and automatically moved to the volume's pool. A rebuild task can be suspended and resumed but cannot be cancelled.NOTE:When the D-Link SAN detects that failure occurred on a drive, it will send a notification to the administrator.
85 Array configured with RAID 1 SAN Product Features OverviewVolume and RAID SupportDrive RoamingD-Link SAN provides feature for safely moving drive in an array .If a drive in an array configured with RAID is accidentally removed, the removed drive can still be recognized using this feature, as long as the drive is configured with RAID that provides fault tolerance (RAID 1 and RAID 5). This is known as drive roaming in power off.Array configured with RAID 1Steps to move the drives safely:Turn off the array in which the removed drive belongs toPlug the removed drive to any slot in the arrayReboot the arrayDrive-0Drive-11122If a drive is accidentally removed in which it is part of a RAID redundant array*, the removed drive still can be recognized when it is returned back to the original array. Before returning the drive to any drive bay in an array, the administrator must be shutting down the array and then restarting the unit after the drive is returned back to the array. The drive will be recognized once again and the unit should be functioning as it did before it was accidentally removed.Note that moving the drives safely around can only be done when the system is powered off. "Drive Roaming in Power Off" simply means that we can shut the unit down, move the drives to any slot we wish, reboot the unit, and we will find that all of the volumes originally created are alive and well functioning.Notes:* In the case of accidentally removing a drive and returning it back to the array, please be aware that only fault-tolerance volumes like RAID 5 and RAID 1 will be able to recover as described above. Any non fault-tolerance RAID, such as RAID 0 will still be unrecoverable.Clients will still need to save their configuration file that includes information about LUNs, network portals, etc. This will be needed in the case of replacement of the entire unit. The metadata on the drives will provide volume information, but all other configuration information needed are still checked from the configuration file that was saved. This is why it is important a client must ensure this file is saved and kept in a safe location.33RemovedPage is Animated
86 Self Monitoring and Reporting Technology (S.M.A.R.T) SAN Product Features OverviewVolume and RAID SupportSelf Monitoring and Reporting Technology (S.M.A.R.T)D-Link SAN Series support Self-Monitoring Analysis and Reporting Technology (S.M.A.R.T.), a technology designed to monitor the reliability of hard drives.The purpose of S.M.A.R.T. is to warn a user or system administrator of impending drive failure while time remains to take preventative action — such as copying the data to a replacement device.Features of S.M.A.R.T. technology include a series of attributes, or diagnostics, chosen specifically for each individual drive model. Attribute individualism is important because drive architectures vary from model to model.Self-Monitoring, Analysis, and Reporting Technology (S.M.A.R.T.) is a monitoring system for hard disks to detect and report on various indicators of reliability, with the hope of anticipating failures. With S.M.A.R.T., a hard disk’s integrated controller works with various sensors to monitor various aspects of the drive's performance, determines from this information if the drive is behaving normally or not, and makes available status information to software that probes the drive and look at it.The xStack Storage Array collects the S.M.A.R.T. information and displays it on the management console in two collections. This information consists of:S.M.A.R.T. data that serves as a summary of the overall status.S.M.A.R.T. attributes that are defined differently by each vendor.When viewing the collected information, the administrator may notice a slight delay, as the xStack Storage Array polls this information from the drive (S.M.A.R.T. data is polled from the drive every 10 seconds).How S.M.A.R.T generates report status?In an ATA/IDE environment, software on the host interprets the alarm signal from the drive generated by the “report status” command of S.M.A.R.T. The host polls the drive on a regular basis to check the status of this command, and if it signals imminent failure, sends an alarm to the end user or system administrator. This allows downtime to be scheduled by the system administrator to allow for backup of data and replacement of the drive. This structure also allows for future enhancements, which might allow reporting of information other than drive conditions, such as thermal alarms, CD-ROM, tape, or other I/O reporting. The host system can evaluate the attributes and alarms reported, in addition to the “report status” command from the disc.
87 Summary: SAN Product Features Overview (1) The xStack Storage unit can automatically, or at the administrator’s demand, performs activities such as volume initialization, volume rebuild, volume expansion, media scanning, and parity scanning.Volume initialization is performed when an initiator (i.e. server) is reading or writing data.With D-Link SAN, the size of a volume can be flexibly expanded up to the maximum capacity of a storage.Media scanning provided in the management console of all D-Link SAN products can be used to scan a JBOD, stripe, mirrored stripe, or mirrored stripe media volume for errors.D-Link SAN provides parity volume scanning to check errors found in the selected volume.Task Manager provides general information for all task activity running on the D-Link SAN.Storage pool information provides comprehensive information about the storage.D-Link xStack Storage series accommodate a 6-cell shrink-wrapped battery pack for backing up the buffer cache contents in case of power failure.D-Link SAN provides an event log feature that tracks the xStack Storage informational, warning, and error messagesTo increase the data transfer performance and prevent bottleneck from occurring, D-Link SAN is provided with link aggregation feature to double the speed performance, depending on the number of the aggregated links.
88 Summary: SAN Product Features Overview (2) All D-Link Storage Area Networks support 802.1Q VLAN tagging to segregate traffic into isolated zone for more secure access.TCP/IP Offload is used to reduce the amount of TCP/IP processing handled by the microprocessor and I/O subsystem to ease server networking bottleneck.CHAP authentication provides secured and encrypted authentication mechanism, and is supported in all D-Link SAN product series. It is used when an initiator tries to connect to its target, and vice versa.D-Link xStack storage virtualizes disk storage for use by a customer's host computer (servers) by grouping all storage devices found across a network to become a single large storage entity that can be centrally managed.When a drive in the storage array fails, xStack storage will automatically detect the failed drive and substitute the failed drive with the hot spare drive.S.M.A.R.T. is a technology supported in D-Link SAN series to monitor the reliability of hard drives and to warn a user or system administrator of impending drive failure while time remains to take preventative action
89 Questions and Answers: SAN Product Features Overview What tasks can be done by D-Link Storage Area Network? (Choose all that apply)Volume InitializationMedia ScanningVolume RebuildError CorrectionVolume ShrinkageWhat cannot be done when an administrator expands a volume and initializes a grow task?Grow task deletionGrow task suspensionGrow task resumptionAll of the above can be done when a grow task is initializedWhat is the function of TCP/IP Offload Engine in D-Link SANTo bypass requests coming from the client over the network when the storage’s CPU is highTo turn off the xStack storage when it detects the TCP/IP utilization is highTo safely move drive in an array by turning off the unitTo reduce the amount of TCP/IP processing handled by the microprocessor and I/O subsystemA, B, CAD
90 Questions and Answers: SAN Product Features Overview What is the function of disk virtualization provided by D-Link SAN?To link multiple storage repositories to multiple clients and servers.To group all storage devices found across a network to become a single large storage entity that can be centrally managedTo create storage clustering that comprises master storage and slave storage, where the slave serves as a backup of the masterTo achieve double data rates by aggregating multi physical links as one logical link.What is the benefit of S.M.A.R.T.?Repair failed disk automatically by doing some diagnoses, analyze the main cause of the error, and perform reparation process depends on the analysis result.Provides 100% guarantee of disk failure prevention by regularly predicting each disk condition and provides maintenance to keep each disk in a good condition.Failure anticipation by regularly monitor all hard disks and report on various indicators of reliability, with the hope of anticipating failures.All of the above.BC
92 D-Link Network Attached Storage (NAS) After this section, you should gain more knowledge of the following:Various D-Link NAS appliances and differences between each of themKey selling points of D-Link NAS appliancesFunctions and applications of D-Link NASProduct positioning of D-Link NAS
93 D-Link Network Attached Storage (NAS) D-Link Products for Network Attached StorageD-Link Network Attached Storage (NAS)DNS-3131 Bay SATA Network Storage EnclosureBuilt-in iTunes, UPnP and FTP ServerMay be used as USB 2.0 portable hard drive (become a DAS enclosure)DNS-3212 Bays SATA Network Storage EnclosureRAID 1 supportDNS-323Built-in iTunes, UPnP, and FTP ServerUSB port for connecting to printerDNS-3434 Bays STA Network Storage EnclosureRAID 1, 5 supportMulti-Functional USB portThe USB port provided at each D-Link NAS (except DNS-321) can be used to connect to the printer server or UPS (Uninterruptible Power Supply) or to make the NAS act as a DAS connected directly to a client.
94 D-Link DNS-313 D-Link Network Attached Storage (NAS) D-Link Products for Network Attached StorageD-Link DNS-313Device Interface1 Gigabit Ethernet port1 USB 2.0 port*FeaturesiTunes and UPnP AV serverScandisk featureReal-time backupalertsPermission settings for user and groupMulti-language file name supportScheduled downloads from web or FTP sitesCan be used as a USB 2.0 portable hard driveSupported Hard Drive TypeOne 3.5-inches SATA Standard Drive with capacity support up to 1.5 TBFile SharingMax. User Account: 64 usersMax. Group: 10 groupsMax. Shared Folder: 45 foldersMax. Concurrent Connection: 64 (Samba) / 10 (FTP)Networking FeaturesDDNSFTPDHCP Server/ ClientNTPHTTP/ HTTPSCIFS/SMB*USB port is used for connecting to a desktop or notebook as a USB2.0 portable drive.
95 D-Link DNS-321 D-Link Network Attached Storage (NAS) D-Link Products for Network Attached StorageD-Link DNS-321Drive ManagementMultiple hard drive configurations (RAID 0, RAID 1, JBOD, Standard)iTunes and UPnP AV serverScandisk featureUser/ group Quota ManagementFile SharingSupport RAID migration (non-RAID to RAID 1)Device Interface1 Gigabit Ethernet portSupported Hard Drive TypeTwo 3.5-inches SATA Standard Drive with capacity support up to 1.5 TBNetworking FeaturesDDNSFTP / FTP over SSL/TLSDHCP Server/ ClientNTPHTTP/ HTTPSCIFS/SMBJumbo FramesFile SharingMax. User Account: 64 usersMax. Group: 10 groupsMax. Shared Folder: 45 foldersMax. Concurrent Connection: 64 (Samba) / 10 (FTP)Device ManagementAlertsPower ManagementEasy Search UtilityMultilingual support
96 D-Link DNS-323 D-Link Network Attached Storage (NAS) D-Link Products for Network Attached StorageD-Link DNS-323Device Interface1 Gigabit Ethernet portUSB port*Features4 different hard drive configurations (Standard, JBOD, RAID 0, RAID 1)iTunes and UPnP AV serverScandisk featurealertsPower managementSupports BitTorrentUSB port supports UPS monitoring and Print ServerSupport RAID migration (non-RAID to RAID 1)Supported Hard Drive TypeTwo 3.5-inches SATA Standard Drive with capacity support up to 1.5 TBNetworking FeaturesDDNSFTP / FTP over SSL/TLSDHCP Server/ ClientNTPHTTP/ HTTPSCIFS/SMBJumbo FramesFile SharingMax. User Account: 64 usersMax. Group: 10 groupsMax. Shared Folder: 45 (without BitTorrent), 10 (with BitTorrent) foldersMax. Concurrent Connection: 64 (Samba) / 10 (FTP)*The USB port provided on D-Link DNS-323 is used to connect to the print server only
97 D-Link DNS-343 D-Link Network Attached Storage (NAS) D-Link Products for Network Attached StorageD-Link DNS-343Drive ManagementMultiple hard drive configurations (RAID 0, RAID 1, RAID 5, JBOD, Standard)iTunes and UPnP AV serverScandiskUser/ group Quota ManagementFile SharingDevice Interface1 Gigabit Ethernet port1 USB 2.0 portSupported Hard Drive TypeFour 3.5-inches SATA Standard Drive with capacity support up to 1.5 TBDevice ManagementUPS MonitoringAlertsPower ManagementEasy Search UtilityMultilingual supportADS supportAuto Power RecoveryNetworking FeaturesJumbo FrameDDNSFTP / FTP over SSL/TLSDHCP Server/ ClientNTPHTTP/ HTTPSCIFS/SMBFile SharingMax. User Account: 64 usersMax. Group: 10 groupsMax. Shared Folder: 45 foldersMax. Concurrent Connection: 64 (Samba) / 10 (FTP)
98 OLED – Special Display on D-Link DNS-343 D-Link Network Attached Storage (NAS)D-Link Products for Network Attached StorageOLED – Special Display on D-Link DNS-343Organic Light-Emitting Diode (OLED) is a LED screen that displays information to enable the administrator to easily view and obtain the status and basic information of the DNS-343Information that can be viewed from the OLED include:System InformationHostname of the DNS-343Firmware versionIP address of the DNS-343Operating temperatureHard Drive StatusSpace percentage used on the hard diskServer StatusStatus of the printer serverStatus of the UPnP AV serverStatus of the iTunes serverStatus of the FTP server
99 Key Selling Point of D-Link NAS D-Link Network Attached Storage (NAS)Market Analysis for D-Link NAS ProductsKey Selling Point of D-Link NASFile-sharing across the local network and Internet using FTP and HTTPSFlexible options for array capacity, supporting up to 1.5TBEasy installationUsers and Groups/Folder with Quota and permission rights (read/ write) managementAppliance servers for network users (printer server, UPnP AV server, etc)iTunes automatic discovery of music stored on the NASPeer to Peer download client support
100 D-Link NAS Functions and Applications D-Link Network Attached Storage (NAS)Market Analysis for D-Link NAS ProductsD-Link NAS Functions and ApplicationsShares and backup files from multiple clientsRemote access via FTPStreams music, photos, and videos from the NAS to a media playerShares printer on the LANConnects to UPS for monitoring functionDownloads shared files from the Internet using BitTorrentStores recorded video surveillance directlyRemote Client(FTP: port 21)Obtains files stored in NASD-Link Multimedia Player(UPnP AV)UPSPrinterConnects through USB port(P2P Connection)Download shared file using P2P connection
101 Product Positioning for D-Link NAS D-Link Network Attached Storage (NAS)Market Analysis for D-Link NAS ProductsProduct Positioning for D-Link NASD-Link NAS products are suitable for home user, SOHO and SMBD-Link Network Storage Enclosures address the ever-growing data storage requirements for multimedia and large data files for small to medium business usersNeed for data consolidation and data sharing make this enclosure an ideal solutionVarious RAID level support offers advanced data protectionThis versatile enclosure supports the latest SATA technology and Gigabit Ethernet connectivity for best-in-class performance
102 Summary: D-Link Network Attached Storage (NAS) D-Link provides four main models for its NAS appliance product line: DNS-313, DNS-323, DNS-321, and DNS-343.All D-Link NAS appliances can be used to act as an iTunes server, UPnP server, FTP server, printer server, and for certain models, D-Link also supports added networking features such as a DHCP server, and advanced features such as quota management and DDNS, etc.D-Link DNS-343 provides an added feature on the box, which is an OLED screen to show certain status information, such as system information, hard drive status, and the server appliance status.D-Link NAS appliances are primarily targeted at home users, SOHO, or SMB users who want the benefits of network storage that is cost effective.
103 Questions and Answers: D-Link Network Attached Storage (NAS) Which model of D-Link NAS provides OLED screen feature on the box?DNS-313DNS-323DNS-321DNS-343What are the functions of D-Link NAS? (Choose all that apply)Easy RAID migration and adaptabilityPlay music from iTunes software with the music stored in NASStream music, photos and videos to a media serverWireless access of data in the NAS via wireless clientWhich RAID features are supported by D-Link DNS-323? (Choose all that apply)RAID 0RAID 1RAID 5RAID 10DA, B, CA, B
104 NAS Product Features Overview* *All features are explained based on the DNS-343 product
105 NAS Product Features Overview After this section, you should gain more knowledge of the following:What is the Easy Search Utility and the functions supported in this featureWhat is the Configuration Wizard and what configuration tasks are available to this wizardWhat is AlertsThe characteristics of power management on D-Link NASFunction of Disk Diagnostic featurePurpose of user and group creation on D-Link NASThe function of quota managementAppliance server roles with/without the use of USB port on D-Link NASRemote BackupPeer-2-Peer (P2P) DownloadsVolume/File sharing on D-Link NAS and scheduled downloading
106 Easy Search Utility NAS Product Features Overview Managing the DeviceEasy Search UtilityEasy Search Utility is provided to help the users find the D-Link NAS on the network.What D-Link Easy Search Utility can:Discover and connect to D-Link NAS products.Map drivesConfigure the IP of the NASEasy Search Utility is a software bundled in a package with the D-Link NAS to help users in the network to easily find and access the D-Link NAS around the network.In order to access the Easy Search Utility software, each user must install the software on their client device. With this software, the user can discover the device, connect to the NAS, and configure and manage the D-Link NAS. The user can also map volumes or folders created on the NAS from this software as long as the user has the proper access rights.
107 Configuration Wizard NAS Product Features Overview Managing the Device The Configuration Wizard is available in all D-Link NAS products, providing easy basic setup, including password setting, time zone setting, LAN connection type setting, and other basic additional information, such as workgroup name, domain name, device name, and description.Password SettingSet a new password for Admin user to access the web manager.Time Zone SettingSet the appropriate time zone for the proper locationLAN Connection Type SettingSet the IP address of the device, either by using a static IP or a dynamic IP from the DHCP server.Additional Information SettingSet the workgroup or domain information, name of the device, and its description.
108 Email Alerts NAS Product Features Overview Managing the DeviceAlertsWith the alerts feature supported in the D-Link NAS product series, alerts can be sent to a specified user if certain operational conditions occur, such as the following:Information about space statusA volume is fullA hard drive has failedAdministrator password has been changedFirmware has been upgradedSystem temperature has exceeded the specified temperature**If the system temperature exceeds the configured threshold, an alert will be sent. After the alert has been sent, the D-Link NAS will be powered off for safety reasons.
109 Power Management on D-Link NAS NAS Product Features OverviewManaging the DevicePower Management on D-Link NASPower management offers a green feature on D-Link NAS products.With this feature, the administrator can configure the drives to shut down after a specified idle time. The device will automatically power up when data is being accessed by the client.
110 Disk Diagnostic NAS Product Features Overview Managing the DeviceDisk DiagnosticScandisk activity can be performed to check if any error has occurred on the hard disk.With this feature, all errors found will be listed with a description, along with the option to repair each of these errors.Scandisk can be performed over selected volume.
111 User and Group Creation NAS Product Features OverviewUser and Group ManagementUser and Group CreationUser and groups can be created and managed on the D-Link NAS product series.The purpose of creating users and groups on the NAS product is to control user access to the storage and to control read/write privileges for specified folders on the network drives, or to setup FTP access rights.By default, all users have read and write access to all folders. Access rules can be created in the Network Access menu.
112 Network Access NAS Product Features Overview User and Group ManagementNetwork AccessThe Network Access feature is used to assign access rights to a user or a group for specific folders or volumes.This section allows you to assign the access rights for your users and groups to specific folders or volumes. By default, all volumes are open to anyone on the local network with read/write access. Before specific user or group rules can be created, the default rules must be deleted.OplocksOpportunistic locks (Oplocks) are characteristics of the LAN Manager networking protocol implemented in the 32-bit Windows family.Opportunistic locking (Oplock) is a mechanism that allows a server to tell a client process that a requested file is only being used by that process. The client can safely do read-ahead and write-behind as well as local caching, knowing that the file will not be accessed or changed in any way by another process while the opportunistic lock is in effect. The server notifies the client when a second process attempts to open or modify the locked file.If a client has oplocks disabled, all requests other than read must be sent to the server. Read operations may be performed using cached or read-ahead data as long as the byte range has been locked by the client; otherwise, they too must be sent to the server.When a client opens a file, it may request that the server grant it an exclusive or batch oplock on the file. The response from the server indicates the type of oplock granted to the client. If cached or read-ahead information was retained after the file was last closed, the client must verify that the last modified time is unchanged when the file is reopened before using the retained information.In general, oplocks are guarantees made by a server to its clients for a shared logical volume. These guarantees inform the client that a file's content will not be allowed to be changed by the server, or if some change is imminent, the client will be notified before the change is allowed to proceed. Oplocks are designed to increase network performance when it comes to network file sharing however when using file-based database applications it is recommended to set the share oplocks to No (Off).By default Windows Vista has Oplocks enabled and cannot be disabled. If you are having network performance issues with applications sharing files from the NAS you may want to try to improve performance by setting Oplocks to No (off).To learn more about Opportunistic Locks, please refer to the following URL:http://msdn.microsoft.com/en-us/library/aa aspxMap ArchiveThe archive bit (on Windows file systems) is used to keep track of whether or not a file has been changed since it was last backed up (archived). Enabling the “Map Archive” option will map the (Windows) archive bit to the Linux (UNIX) owner execute bit, so as to preserve this part of the file’s attribute under a Linux file system. The Linux (UNIX) file system lacks the concept of an archive bit. It is recommended that you enable this option if you are performing backups on a Windows system or if you are using applications that require the archive bit. Certain backup software will attach this attribute to files that are being stored as backups, and as such, archive bits are used in incremental backups
113 Quota Management NAS Product Features Overview User and Group ManagementQuota ManagementThe D-Link NAS product series supports quota management for groups, folders, and individual users.Assigning quotas to a groups, folders, or users will limit the amount of storage capacity allocated for them.By default users, groups, and folders do not have a quota and therefore the storage space assigned for each user/group/folder is unlimited.
114 Quota Illustration NAS Product Features Overview User and Group ManagementQuota IllustrationVolume-1Saving Data Failed!!!Quota Exceeded!!!Current available space for Robert is 1GBData saved!!! Current available space for Robert is 100MBData saved!!! Current available space for Robert is 400MBD-Link NASSaves 200MB data to volume-1Saves 600MB data to volume-1Saves 300MB data to volume-1From the animation above, we can see that by using quotas, one user space for storage capacity can be set and limited up to a certain number.RobertQuota limit for Robert is 1GBPage is Animated
115 FTP Server NAS Product Features Overview Appliance ServersFTP ServerThe D-Link NAS product series are equipped with a built-in FTP Server. With this feature, data resources kept in the NAS can be accessed via FTP, both from the inside and outside network.The D-Link NAS product series are equipped with a built-in FTP Server. The server is easy to configure and allows up to 10 users to access the server locally or remotely at the same time.If this feature is activated, the D-Link NAS will immediately act as an FTP server and users or groups can access the NAS from the Internet. Users and groups will only be allowed to access folders for which they have been granted access rights to.Note that each username or group name will only create one profile on the FTP server.
116 UPnP AV Server NAS Product Features Overview Appliance ServersUPnP AV ServerUPnP (Universal Plug and Play) is a set of network protocols that allows devices to connect seamlessly and to simplify the implementation of networks in the home digital environment (data sharing, communications, and entertainment) and/or corporate environments.UPnP AV (Audio and Video) servers store and share digital media, such as photographs, movies, and music to provide hardware-based media streaming services to UPnP AV compatible clients on the local network.The D-Link NAS product series supports media streaming to UPnP AV compatible clients on the local network. Use the UPnP AV server menu to select the media content made available to such clients. By default the UPnP server is enabled. The “root” checkbox specifies access to media content on all volumes and folders on the drive.Two main components of UPnP AV:UPnP MediaServer DCP - which is the UPnP-server (a 'slave' device) that shares/streams media data (like audio/video/picture/files) to UPnP-clients on the network. In this case, D-Link’s NAS box is the UPnP Media Server DCP.UPnP MediaServer ControlPoint - which is the UPnP-client (a 'master' device) that can auto-detect UPnP-servers on the network to browse and stream media/data files from them.When using this function, a UPnP MediaServer ControlPoint is able to auto-detect UPnP-servers on the network to browse and stream media/data files from them.
117 iTunes Server NAS Product Features Overview Appliance ServersiTunes ServerD-Link NAS comes with a feature in which end users can listen to music from iTunes at their own desk with the music files stored in the NAS.With this feature, the iTunes software will automatically detect the folder specified by the administrator. Therefore the administrator must specify a folder that contains a collection of songs stored on the NAS.The D-Link NAS product series feature an iTunes server. This server provides the ability to share music and videos to all the available computers within your local network. If the server is enabled, the folder shared by the NAS will be automatically detected by the iTunes program, and the music and videos contained in the specified directory will be available for streaming over the network.
118 iTunes at the Client Side NAS Product Features OverviewAppliance ServersiTunes at the Client SideSong library stored on the D-Link NAS is automatically detected using the iTunes application on the client sideD-Link NASiTunes server feature is activated on the D-Link NASPlay music from the NAS with iTunes
119 DDNS NAS Product Features Overview Networking FeaturesDDNSDynamic DNS (DDNS) allows the hosting of a server using a domain name assigned with a dynamic IP address.DDNS helps to deal with servers publishing IP addresses that constantly change due to the use of dynamic IP addresses.In the D-Link NAS product series, the DDNS feature can be used to make the NAS accessible from a public network.D-Link provides a utility for customers to use the DDNS service provided by (only 1 host may be created using the D-Link DDNS service).Free DDNS service can also be obtained fromThe DDNS feature allows you to host a server (Web, FTP, Game Server, etc) using a domain name that you have purchased (www.whateveryournameis.com) with your dynamically assigned IP address. Most broadband Internet Service Providers assign dynamic (changing) IP addresses. Using a DDNS service provider, your friends can use the domain name to connect to your server no matter what your IP address is.
120 Remote Backup NAS Product Features Overview Networking FeaturesRemote BackupThe D-Link NAS Remote Backup allows you to backup the files stored on the NAS to one or more remote NAS devices in order to prevent data loss in the event of a failure.D-Link’s NAS Remote Backup feature uses a Secure Shell (SSH) connection that dynamically creates secure key pairs to encrypt the data, ensuring that your data is reliably backed up or restored securely.Supports 10 concurrent downloads to multiple destination devices, providing efficient and comprehensive backups.When configuring the NAS for backup, the user must decide whether to configure the NAS as a Destination device or a Source device. As a Destination device, the Remote Backup feature allows you to browse to the shared backup folders setup on a Source device. The shared backup folder located on the Source device is encrypted before being sent to the Destination devices.
121 Peer-2-Peer (P2P) Download NAS Product Features OverviewNetworking FeaturesPeer-2-Peer (P2P) DownloadThe D-Link NAS P2P Downloads allows the user to share files and folders via torrents. This is a great way to share files with friends, colleagues, and family.
122 NAS Product Features Overview Networking FeaturesFile SharingD-Link NAS provides two ways to share files to all users over the networkSambaSamba is an Open Source/Free Software suite that provides seamless file and print services to SMB/CIFS clients and allows interoperability between Linux/Unix servers and Windows-based clients.FTPFor file sharing, D-Link also provides multilingual support for the local user to easily share files without any difficulties.Samba: UnicodeFTP Client:Croatian, Cyrillic (Kyrgyz Republic), Czech, Danish, Dutch, English, Finnish, French, German, Greek, Hungarian, Italian, Japanese, Korean, Norwegian, Polish, Portuguese, Romanian, Russian, Simplified Chinese, Slovenian, Spanish, Swedish, Traditional Chinese, Turkish.Computers communicate in numbers. In texts, each number is translated to a corresponding letter. The meaning that will be assigned to a certain number depends on the character set (charset) that is used.A charset can be seen as a table that is used to translate numbers to letters. Not all computers use the same charset (there are charsets with German umlauts, Japanese characters, and so on).One standardized multibyte charset encoding scheme is known as Unicode. A big advantage of using a multibyte charset is that you only need one. There is no need to make sure two computers use the same charset when they are communicating.Old Windows clients use single-byte charsets, named codepages, by Microsoft. However, there is no support for negotiating the charset to be used in the SMB/CIFS protocol. Thus, you have to make sure you are using the same charset when talking to an older client. Newer clients (Windows NT, 200x, XP) use Unicode.
123 Scheduled Downloading NAS Product Features OverviewNetworking FeaturesScheduled DownloadingThe D-Link NAS Download Scheduling feature allows the administrator to set up a schedule for downloading folders or files, and backup sessions.By default all local backups and file/folder downloads are in Overwrite mode, meaning that identical files in the destination folder will be overwritten by the source files regardless of which file is newer. Checking Incremental Backup will have the D-Link NAS appliance compare identical file names at the source and destination, and files will only be overwritten if the source file is more recent.
124 Printer attached to the NAS can be accessed from the client side NAS Product Features OverviewUSB Port ApplicationsPrint ServerThe D-Link NAS can be directly connected to a printer to make the NAS become a print server.D-Link NAS features a built-in USB print server, giving users the ability to share a printer on their local network. Connect a USB printer to the USB port on the back of the D-Link NAS. It is important to ensure that all the printer’s drivers have been installed on the computers you want to print from.Printer attached to the NAS can be accessed from the client side
125 UPS Monitoring NAS Product Features Overview USB Port ApplicationsUPS MonitoringAn Uninterruptible Power Supply (UPS) can be directly connected to a D-Link NAS through the provided USB port.The purpose of attaching the UPS to the NAS is to provide a way to safely shutdown the NAS in case of a power failure.When a UPS (Uninterruptible Power Supply) is connected to the NAS, the Status screen hides the printer information and displays information about the UPS (such as, the manufacturer, product type, battery power status, and UPS status).Status of the UPS:OL indicates that the UPS is onlineOB indicates that the UPS is running on battery, meaning that there has been a power failure. In this case, the D-Link NAS will keep running by consuming the battery power of the UPS. Any data should be save immediately to prevent data loss before the battery power on the UPS runs out.LB indicates that the UPS has low battery power.
126 Summary: NAS Product Features Overview (1) The Easy Search Utility is a feature in D-Link NAS that helps make the administrator's task easier by displaying all the D-Link NAS products found within the subnet. Besides providing NAS discovery, it can also be used to map drives and configure IP addresses.To make device configuration easier, D-Link NAS provides a configuration wizard to perform the basic configuration of the device. This is useful for some users who are unfamiliar with configuring the device.alerts is a feature which warns a specified user, usually the administrator, when certain conditions, as specified by the administrator, are encountered.Power management is a feature designed to help cut down on the energy used by the NAS. With this feature the D-Link NAS will automatically shutdown after being idle for some specified amount of time.D-Link provides the Disk Diagnostic feature which can be used to perform error checking on a disk. This is to ensure the integrity of the data stored on the disk.Users and groups can be created and managed on the D-Link NAS to better control user access to the data stored on the NAS. Quotas can also be applied to users/groups/folders.
127 Summary: NAS Product Features Overview (2) All D-Link NAS can be set to act as application servers serving added functionality to its clients, such as to act as an iTunes server, UPnP server, FTP server, and print server.Dynamic DNS (DDNS) is a feature which can be used to host a server using a dynamic IP address by giving the host a domain name so it is accessible by the public.With a NAS appliance, file sharing over the network becomes much easier by sharing a volume all at once using the drive mapping feature. File sharing can also be done by using FTP or Samba.The D-Link NAS appliance can be instructed to perform scheduled downloading from a specified URL.An Uninterruptible Power Supply (UPS) can be connected to a D-Link NAS through the provided USB port to provide a safe shutdown after a power failure.
128 Questions and Answers: NAS Product Features Overview What is the function of the Easy Search Utility feature?To search for files stored in the D-Link NAS based on keywords or file extensions.To find errors that have occurred on the D-Link NAS.To discover D-Link NAS products over the network.To search the activity history saved on the D-Link NAS.What feature on D-Link NAS is used to check errors that have occurred in the hard disk?Scan DiskMedia ScanningParity ScanningDisk ScanningHow many concurrent users are allowed to access FTP in D-Link NAS?1410UnlimitedWhat are the purposes of USB port provided in D-Link NAS? (Choose all that apply)To make the NAS become a print server if connected to a printer from the USB port.To connect to iPod to synchronize music from the iPod to the NAS.To connect to a USB scanner so it can scan a file directly.To connect to a UPS to enable a safe shut down upon power failure.CAA, D
129 Questions and Answers: NAS Product Features Overview What feature must be used to publish a D-Link NAS for public access when it is assigned a dynamic IP address rather than a static IP address?DNSFTP ServerD-Link UPnP AV ServerDDNSWhat are the appliance server functions supported by D-Link NAS? (Choose all that apply)iTunes ServerDNS ServerWeb ServerUPnP AV ServerWhat is the method used to share files on the D-Link NAS if using remote access?FTPTelnetSSHDA, C, EB
130 Applications and Solutions for Network Storage
131 Applications and Solutions for Network Storage After this section, you should gain more knowledge of the following:NAS application for sample referenceSAN application for sample reference
132 NAS Application for SMB Environment Applications and Solutions for Network StorageNAS ApplicationsNAS Application for SMB EnvironmentWireless RouterThe USB port can be attached to a UPS or USB PrinterDNS-343Wireless ClientsWireless LANWired LANGuest-1Guest-2Employee-1Employee-2Printer is shared by the NAS, therefore can be accessed over the network
133 SAN Application for Server Clustering Applications and Solutions for Network StorageSAN ApplicationsSAN Application for Server ClusteringServer clustering is a group of servers running the same application as a single virtual server.Server clustering prevents a single point of failure. If a server is goes down, another server will replace it and take the role of the primary server.In this scenario, the clustered servers share the same disks in the SAN.Clustered ServersClustered ERP ServersGoes to Public NetworkiSCSI SANTape Libraries
134 SAN Application for Monitoring Purposes Applications and Solutions for Network StorageSAN ApplicationsSAN Application for Monitoring PurposesLinks are aggregatedGigabit Ethernet SwitchSAN StorageVideo Server with iSCSI initiatorWired Video CamerasWireless CameraD-Link Wireless N RouterVideo Post Processing ServerRecorded videos from all cameras are stored directly into the SAN storageBackup Storage