1. Copyright © 2014 EMC Corporation. All Rights Reserved. Host Integration Basics Upon completion of this module, you should be able to: Identify storage network topologies and requirements Describe PowerPath features and functions Describe Unisphere Agent and Unisphere Server Utility considerations Host Integration Basics1

2. Copyright © 2014 EMC Corporation. All Rights Reserved. Host Integration Basics This lesson covers the following topics: Identifying Network Technologies Identifying Fibre Channel components, addressing, and Connectivity rules Identifying iSCSI components, addressing, and Connectivity rules Explaining host connectivity requirements Lesson 1: Storage Network Topologies and Requirements Host Integration Basics2

3. Copyright © 2014 EMC Corporation. All Rights Reserved. Network Technologies Network technologies offer more flexibility and distance capabilities than typical channel technologies Some characteristics of network technologies are: Low performance High protocol overhead Dynamic configuration Long distance Connectivity among different systems 3Host Integration Basics

4. Copyright © 2014 EMC Corporation. All Rights Reserved. Storage Area Network Management SANs are networks of host and storage devices often connected over Fibre Channel Fabrics A common method of managing the variety of devices on a SAN is SNMP  Out of Band The FibreAlliance is defining the SNMP MIB to facilitate SAN management  The Fibre Channel Management Integration (FCMGMT-INT) MIB provides a heterogeneous method of managing multiple devices across a SAN 4Host Integration Basics

5. Copyright © 2014 EMC Corporation. All Rights Reserved. Fibre Channel Fibre Channel is a serial data transfer interface  Copper Wire Connection  Optical Fiber Connection High-speed is obtained through:  Mapping networking and I/O protocols to Fibre Channel constructs  Encapsulating them and transporting them within Fibre Channel frames Fibre Channel Switch Windows Host Linux Host Storage Host Bus Adapters 5Host Integration Basics

6. Copyright © 2014 EMC Corporation. All Rights Reserved. Host Bus Adapter (HBA) Manages the transfer of information A Host Bus Adapter is an I/O adapter that sits between the host computer's bus and the Fibre Channel loop Minimizes the impact on host processor performance Performs many low-level interface functions automatically Fibre Channel iSCSI FICON SCSI Multiple Technologies Load balance Fail-over SAN administration Storage management The HBA enables a range of high-availability and storage management capabilities 6Host Integration Basics

7. Copyright © 2014 EMC Corporation. All Rights Reserved. Fibre Channel Addressing Fibre Channel Addresses are required to route the frames from source to target 24 bits (3 bytes) physical addresses are assigned when a Fibre Channel node is connected to the switch (or loop in the case of FC-AL) Target Source FC Initiator: HBA FC Responder: SP Ports FC Switch 7Host Integration Basics

8. Copyright © 2014 EMC Corporation. All Rights Reserved. Viewing SP Fibre Channel Port Properties 8Host Integration Basics

9. Copyright © 2014 EMC Corporation. All Rights Reserved. Switched Fabric Topology Switched Fabric is a Fibre Channel topology where many devices connect with each other via Fibre Channel switches  This topology allows for the most number of connections with a theoretical 16 million devices per Fabric Frames are routed between source and destination by the Fabric Fibre Channel Switch 9Host Integration Basics

10. Copyright © 2014 EMC Corporation. All Rights Reserved. Always put ONLY one HBA in a zone with Storage ports Each HBA port can only talk to Storage ports in the same zone HBAs & Storage Ports may be members of more than one zone HBA ports are isolated from each other to avoid potential problems associated with the SCSI discovery process Single Initiator Zoning Host Integration Basics10 Single Emulex HBA zoned to two VNX ports

11. Copyright © 2014 EMC Corporation. All Rights Reserved. iSCSI Overview iSCSI An IP-based protocol for establishing and managing connections between IP-based storage devices, hosts, and clients A method to transfer block data using a TCP/IP network Works by wrapping SCSI commands into TCP Packets to transport them over an IP network. Route or switch on standard Ethernet equipment. Can use existing TCP/IP infrastructure Bridging devices can be used between IP network and SAN No Fibre Channel content needed IP Network FC iSCSI/FC Gateway 11Host Integration Basics

12. Copyright © 2014 EMC Corporation. All Rights Reserved. iSCSI Device Options Network Interface Card (NIC) Checksum offload Fragmentation, out of order packets handled by host Could hurt system performance NIC with TCP Off-load Engine (TOE) Full TCP/IP offload Fragmentation, out of order packets handled by TOE Increased memory/processing requirements iSCSI & SCSI handled by host iSCSI Host Bus Adapter (HBA) Full TCP/IP+iSCSI/SCSI Completes storage connection Runs all layers on HBA 12Host Integration Basics

13. Copyright © 2014 EMC Corporation. All Rights Reserved. iSCSI Names An iSCSI address  Uniquely identifies nodes  There are Two variations  iqn. – iSCSI Qualified Name  iqn.1992-04.com.emc:cx.fcntr073900083.a4  eui. – Extended Unique Identifier  eui.5006016141e0163a 13Host Integration Basics

14. Copyright © 2014 EMC Corporation. All Rights Reserved. iSCSI Front-end Port Properties Host Integration Basics14

15. Copyright © 2014 EMC Corporation. All Rights Reserved. iSCSI CHAP Security Challenge Handshake Authentication Protocol 1. CHAP Target sends challenge to CHAP initiator 2. Initiator responds with a calculated value to the target 3. Target checks the calculated value, and if it matches, login continues 4. If mutual CHAP is enabled, initiator will authenticate target using the same process One-way and Mutual CHAP  Target and Initiator configured the same Configuration  Unisphere – Array  Host NBAs – Vendor Specific Tools 15Host Integration Basics

16. Copyright © 2014 EMC Corporation. All Rights Reserved. iSCSI Network Requirements LAN configuration allows Layer 2 (switched) and Layer 3 (routed) networks  Layer 2 networks are recommended over Layer 3 networks The network should be dedicated solely to the iSCSI configuration  For performance reasons EMC recommends that no traffic apart from iSCSI traffic should be carried over it  If using MDS switches, EMC recommends creating a dedicated VSAN for all iSCSI traffic.  The network must be a well-engineered network with no packet loss or packet duplication.  vLAN tagging protocol is supported 16Host Integration Basics

17. Copyright © 2014 EMC Corporation. All Rights Reserved. Ping  Check basic connectivity Trace Route  Provides information on number of hops required for the packet to reach its destination iSCSI Basic Connectivity Verification Host Integration Basics17

18. Copyright © 2014 EMC Corporation. All Rights Reserved. iSCSI and FC Host Connectivity Rules All connections from a host to an array must use the same protocol  Connections must be all FC or all iSCSI  NIC and HBA iSCSI connections cannot be mixed in the same server  A server must have all NIC iSCSI connections or all HBA iSCSI connections  Do not connect a single server to both an FC storage system and an iSCSI storage system Servers with iSCSI HBAs and servers with NICs can connect to the same iSCSI storage system Host Integration Basics18

19. Copyright © 2014 EMC Corporation. All Rights Reserved. Host Integration Basics During this lesson the following topics were covered: Identifying Network Technologies Identifying Fibre Channel and iSCSI components and addressing Explaining FC and iSCSI connectivity rules Explaining host connectivity requirements Lesson 1: Summary Host Integration Basics19

20. Copyright © 2014 EMC Corporation. All Rights Reserved. Host Integration Basics This lesson covers the following topics: Describe PowerPath Features and Functions Describe Unisphere Agent and Unisphere Server Utility Considerations Implement Host Utilities Lesson 2: PowerPath and Other Host Utilities Host Integration Basics20

21. Copyright © 2014 EMC Corporation. All Rights Reserved. PowerPath Provides Path Management Host-Based Software Multiple Storage System Support Multiple OS Support Supports Fibre Channel and iSCSI Host Integration Basics21

22. Copyright © 2014 EMC Corporation. All Rights Reserved. Features and Functionality Automatic path failover and path restore HBA/NIC Interconnect Switch Interface Interface Port Dynamic multipath load-balancing Host by Host basis Host Integration Basics22

23. Copyright © 2014 EMC Corporation. All Rights Reserved. Array and OS Support Supports all EMC-branded storage arrays All currently-shipping and supported models of VNX Both Fibre Channel and iSCSI interconnects Supports several third-party, non-EMC storage arrays IBM ESS (Shark) Hitachi Lightning HP-branded Hitachi (HPXP) HP StorageWorks EVA EMA HSG80 Supports major host operating systems Solaris Windows Server HP-UX Linux Enterprise (Red Hat and SUSE) Host Integration Basics23

24. Copyright © 2014 EMC Corporation. All Rights Reserved. Integration with Volume Managers Logical Volumes reside above native devices and PowerPath devices in the I/O stack PowerPath has been qualified for compatibility with most major third-party volume managers Solstice Disk Suite, Veritas, VCS on Solaris Veritas, native LVM on HP-UX Veritas, native LVM on AIX Sistina LVM on Linux Host Integration Basics24

25. Copyright © 2014 EMC Corporation. All Rights Reserved. Device States A native device path can be in one of two States: Live: the path is usable for I/O activity Dead: the path has been detected as Failed by PowerPath All paths are tested periodically for a possible change of state Dead paths are restored automatically by PowerPath after they are repaired Only paths currently marked Live by PowerPath can service I/O requests, and participate in load-balancing Host Integration Basics25

26. Copyright © 2014 EMC Corporation. All Rights Reserved. Device Modes Reserves Bandwidth Mode can be set per LUN Path is available to PowerPath for servicing I/O Default Mode, can be manually changed by the administrator Active mode Path is available to PowerPath, but is not servicing I/O Used in failure scenarios Standby Mode Host Integration Basics26

27. Copyright © 2014 EMC Corporation. All Rights Reserved. Active/Passive Arrays: Failover Mechanism Two types of path failover:  Array-initiated LUN trespass  Typical cause: an SP fails or needs to reboot  PowerPath logs a follow-over  Host-initiated LUN trespass  PowerPath detects a path failure, e.g. due to a cable break, port failure etc.  PowerPath initiates a trespass, and logs the event Fabric A Fabric B SP-A PassiveActive SP-B Trespass Host Host Integration Basics27

28. Copyright © 2014 EMC Corporation. All Rights Reserved. Active/Active Mode (ALUA) Asymmetric Logical Unit Access (ALUA)  Asymmetric accessibility to logical units through various ports  Request forwarding implementation  Communication method to pass IO’s between SP’s  Software on the controller forwards requests to the other controller Not an Active-Active Array model!  I/Os are not serviced by both SPs for a given LUN  I/Os are redirected to the SP owning the LUN Front-End Fault Masking Back-End Fault Masking Host Integration Basics28

29. Copyright © 2014 EMC Corporation. All Rights Reserved. LUN Cache Coherency Links LUN Symmetrical Active-Active: Overview Only one SP serves IOs via a given LUN The remaining SP is acting as standby SP trespasses LUN when paths fail and host software adjusts to new path LUN is presented across both SP- paths via internal links Only one SP is actively processing IO to the backend Host initiates trespass when path fails Both SPs serve IOs to and from a given LUN If path fails, no disruption to LUN The performance is now improved up to 2X Classic LUNs only! LUN CX: Active-Passive Active-Active (Symmetrical) VNX: Active-Active (ALUA) Host Integration Basics29

30. Copyright © 2014 EMC Corporation. All Rights Reserved. Asymmetric LUN Access: VNX SP reports SCSI descriptor:  TARGET_PORT_GROUPS  Active/Optimized  Active/Non-Optimized SPA SPB I/O resumes to LUN through alternate SP after short delay SPA SPB Optimized Path Non-optimized Path ALUA masks the failure and trespasses LUN Owned by SPA Owned by SPB Host Integration Basics30

31. Copyright © 2014 EMC Corporation. All Rights Reserved. SPA SPB Owned by SPA Symmetric LUN Access: VNX with MCx SPA SPB Both SPs send and receive  Active/Optimized Classic LUNs ONLY (OE R5.33) Optimized Path Non-optimized Path Owned by SPA I/O continues through remaining SP and paths with NO delay Host Integration Basics31

32. Copyright © 2014 EMC Corporation. All Rights Reserved. SPA SPB LUN Parallel Access Locking Service Required for Active-Active access LUN Lock Write I/O operation acquires a lock on LBA address on both SPs Lock requests sent over CMI Lock requests are smaller/quicker than the entire I/O Write I/O operation acquires a lock on LBA address on both SPs Lock requests sent over CMI Lock requests are smaller/quicker than the entire I/O CMI Host Integration Basics32

33. Copyright © 2014 EMC Corporation. All Rights Reserved. Lower risk with increased availability within data centers Improved Availability  All Paths are Active  No trespass during path failure  No trespass during NDU No setup on VNX or Host side Improved Performance  All Paths serving I/O  Up to 2X Improvement VNX with Symmetric / Active-Active Benefits Eliminate application timeouts Improve application throughput Multi-path load balancing Eliminate application timeouts Improve application throughput Multi-path load balancing LUN Host Integration Basics33

34. Copyright © 2014 EMC Corporation. All Rights Reserved. Requirements for Unisphere Host Agent, Unisphere Server Utility Supported version of the operating system EMC VNX supported HBA hardware and driver installed Each SP must have an IP connection Have a configured TCP/IP network connection to any remote hosts Host Integration Basics34

35. Copyright © 2014 EMC Corporation. All Rights Reserved. Installing Unisphere Host Agent or Server Utility Host agent and server utility can be installed on the same attached server If both are installed: Registration feature of the server utility will be disabled The host agent will be used to register the server’s NICs or HBAs to the storage system Host Integration Basics35

36. Copyright © 2014 EMC Corporation. All Rights Reserved. Unisphere Server Utility: Install Rules for NIC Initiators Must use Unisphere Server Utility Microsoft iSCSI initiator, you must install the Microsoft iSCSI Software Do not install the server utility on a VMware Virtual Machine. Do not disable the Registration Service option Reboot the server when the installation Host Integration Basics36

37. Copyright © 2014 EMC Corporation. All Rights Reserved. Host Integration Basics During this lesson the following topics were covered: Describe PowerPath Features and Functions Describe Unisphere Agent and Unisphere Server Utility Considerations Implement Host Utilities Lesson 2: Summary Host Integration Basics37

38. Copyright © 2014 EMC Corporation. All Rights Reserved. Summary Key points covered in this module: Each network technology has key components, addressing, and connectivity requirements that must be followed to enable host connectivity. PowerPath provides path management essential for multipathing and high availability. Host Integration Basics38