OSD TWG 1 Mike Mesnier January 2003 Object-based Storage 101 SNIA

OSD TWG 2 Storage Trends/Facts Storage is moving to the network –Servers connect to consolidated NAS or SAN storage Storage and networking fabrics are converging –iSCSI, iFCP, RDMA/TCP, … Storage is becoming more autonomous –Standards for richer interfaces and protocols –More functionality in the storage device –Research focusing on intelligent storage Self-aware, self-managing, self-configuring

OSD TWG 3 SwitchedFabric Compute and storage platforms are tailored for specific functions. DB Servers File Servers Web Servers Load Balancers SAN Storage Building Blocks Storage Bricks Compute Bricks Tonight’s Talk Evolving Data Center Fire Walls

OSD TWG 4 Imagine a storage brick that is: –Always available and reliable –Self-securing –Self-managed –Infinitely scalable (i.e., stackable) Object-based storage is a step closer… Storage Utopia

OSD TWG 5  Storage today Emerging solutions Object-based storage SNIA activity Agenda

OSD TWG 6 Storage App. HOST … Direct Attached Storage CLIENT Network … File System Network Attached Storage Storage App HOST Storage App HOST Network … Storage Area Network How did these evolve? Local StorageShared DataShared Capacity Architectures Today

OSD TWG 7 DAS – physically secure and simple –Not scalable –Limited connectivity for capacity sharing –No data sharing SAN – scalable capacity sharing –Limited (coarse) security through switch –No data sharing NAS – secure sharing (data or capacity) –Limited scalability The Trade-offs

OSD TWG 8 DAS and SAN provide raw block storage –No model for the stored data (e.g., files) –No support for data sharing (e.g., concurrency control) Storage applications built using DAS or SAN –File systems, databases, video servers, etc. –App. implements a data model (e.g., a file) –May implement direct data sharing (e.g., via clustering) NAS is an application for indirectly sharing data –Servers export local file systems over the network –Clients share data by sharing files The Usage Models

OSD TWG 9 Data centers need to share data. –Backup, HSM –Clustering for scalability (e.g., file server and db) Sharing data directly on the SAN is difficult. –Concurrency control, lock management, versioning –Distributed security Sharing data through NAS is easy –But imposes limits in scalability Single point of failure & bottleneck Challenge: Data Sharing

OSD TWG 10 Storage today  Emerging solutions Object-based storage SNIA activity Agenda

OSD TWG 11 Virtualization (NAS & SAN) –Aggregates heterogeneous NAS and SAN devices Clustering the file system –Mitigates file server bottleneck Giving clients direct access to storage devices –File servers share block metadata with clients –Eliminates file server bottleneck Changing the device interface –From blocks to objects Emerging Solutions

NAS Clients e.g. Web servers SAN Islands NAS Islands SAN Virtualization NAS Virtualization Clients need direct access to remove bottleneck. Network FILES + Clustering BLOCKS 1 st Generation File Server OSD TWG

OSD TWG 13 Servers Block-Based Storage Block-Based Storage MANAGEMENT Eth switch Trusted SAN DATA Clients Clients METADATA Must be trusted Difficult to directly share 2 nd Generation File Server

OSD TWG 14 Storage today Problems and partial solutions  Object-based storage SNIA activity Agenda

OSD TWG 15 ID x123 Blocks:3,42 Length:512 Objects can be self-describing! An object comprises –Application data (e.g., file, record) –Device-managed metadata (e.g., block allocation) –User-accessible attributes (e.g., access times) Objects have file-like methods for access –Open, close, read, write, get/set attributes –Commands are authorized Object-based storage devices –Disk drive, appliance, controllers Object Storage

OSD TWG 16 Object Storage Model Block Interface Storage Device Block I/O Manager Object Interface Applications File System User Component File System Storage Component System Call Interface CPU Applications File System User Component System Call Interface CPU Storage Device Block I/O Manager File System Storage Component

OSD TWG 17 So What’s the Real Value of Objects?

OSD TWG 18 The Value of Objects Better security via capabilities –Each object can have its own security domain –All I/O is authorized by the device Easier to share data –Files and records can be stored as objects –Low-level metadata managed by device Opportunities for intelligence –Attribute-based learning for resource allocation Better caching, pre-fetching and staging of data –Self-configuring storage w/ continuous reorganization Layout objects to best serve client requests

OSD TWG 19 Separates policy from enforcement –Storage managers set policy –Storage devices enforce the policy Prevents unauthorized access Minimizes interaction with storage manager Minimizes state kept on device –For better scalability, recovery and cost Value #1: Security

OSD TWG 20 Security Types Types of security –Authentication – “you are who you say” –Authorization – “you have permission” –Integrity – “data is not corrupted/modified” –Privacy – “data is not seen” TWG is considering two scenarios –Channel is trusted –Channel is not trusted OSD handles all but authentication.

OSD TWG 21 Preventable Attacks Snooping or modification of commands and data Unauthorized access via modified capability Delay and replay attacks Guards against these attacks, respectively: –Transport or app-level encryption for privacy –Transport or app-level digests for integrity –Cryptographically secure capability –Nonce (timestamp) attached to each command Requires loosely synchronized clocks Only needed when channel is not trusted

OSD TWG 22 Less metadata to keep coherent –No block allocation or free block lists –Shorter “lists” to manage Objects may contain aggregation metadata –Leads to better scalability Backup and HSM –No need to co-locate w/ application (e.g., file system) –Only backup necessary objects (not entire volume) Value #2: Data Sharing OSD is really a file system less the naming

OSD TWG 23 3 rd Generation File Server Managers Object-based Storage Devices MANAGEMENT Eth switch SAN Clients SECRETKEY SECRETKEY SECRETKEY Access Request DATA Intelligent Device Space Management Backup/Recovery QoS via attributes Security Validate Capability

OSD TWG 24 Objects can have rich attributes –Timestamps, accounting information, QoS parameters, group and user information, client-specific usage patterns Many opportunities for policy-based management –E.g, attributes may describe backup and QoS policies Attributes may also provide “information gain” –An object’s actions may be correlated with its attributes E.g., Any object written within the last 24 hours will be read up at 4 a.m. the following day (i.e., for backup) Can devices actually learn?? –This is an active research topic –OSD facilitates a further investigation –Big questions: which attributes really matter? Value #3: Intelligence

OSD TWG 25 Storage today Emerging solutions Object-based storage  SNIA activity Agenda

OSD TWG 26 Charter and Program of Work: –Requirements for OSD –Transport independent definition of OSD –SCSI Standard for OSD –White papers & industry demonstrations ~100 members and over 30 organizations –academia, industry, National Laboratories and startups. The SNIA TWG for OSD

OSD TWG 27 Establishing the commands – v1 DONE Establishing the attributes – v1 DONE Security architecture – v1 DONE How should we identify and locate objects? How to maintain integrity through failures? Should we support transactional semantics? Management of hundreds or thousands of OSDs. Work Items in the TWG

OSD TWG 28 OSD Functions Security Authorization Integrity Privacy Attributes Aid to file systems Hints to device QoS and Priorities Logging & Statistics Basic Protocol –Read –Write –Create –Delete –Open –Close –Get –Set –Append –Clear Basic I/O Space Mgmt Session “hints” Attributes Other cmds

OSD TWG 29 A big challenge in the enterprise is data sharing –Must be secure and scalable Objects complement existing technologies –Add security, low-overhead data sharing and intelligence –Enable the 3 rd generation file server OSD is more active now than ever –SNIA has become the focal point –Will complete v1 SCSI standard 1 st half of this year. Summary

OSD TWG 30 Call to Action How must your file system change to support OSD? How will OSD change your backup story? See the latest OSD standard at T10 Understand our plans for other transports Get involved in the OSD TWG –Architecture –Standards efforts –Industry demonstrations

OSD TWG 31 Academic research – – –csl.cse.ucsc.edu/obsd.shtml Standards work – – – (see OSD) Industry research & development – Download OSD Reference Code – – – Further References

OSD TWG 32 Our Leaders Mike Mesnier, Julian Satran (co-Chairs) Applications – Erik Riedel Education – Tom Ruwart Management – Ken Samarra Security – Michael Factor Contact us to get involved!