Storage Virtualization Strategies

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Storage Virtualization Strategies

• Arun Taneja
• Founder, Taneja Group
• September 25, 2006

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Agenda

• Next Generation Data Center Virtualization
• Storage Virtualization Approaches, Architecture,
  Players
• Other Types of Virtualization their Impact on
  Storage
• Recommendations to End Users

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Compute Networking and Storage Virtualization

• Pools of commonly grouped physical resources
• Dynamic allocations based on application level
  grouping and usage policies
• Interconnected and controlled through an
  intelligent interconnect fabric

Stand-By
Server Processing
I/O
Storage
Applications
Resource Pool
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Virtualized Data Center

• Four main types of virtualization technologies
  emerging
• Server Virtualization
• Virtualizes the physical CPU, Memory, I/O of
  servers
• I/O Virtualization
• Virtualizes the physical network topology and
  mappings between servers and storage
• File Virtualization
• Virtualizes files and namespaces across file
  servers
• Storage Virtualization
• Virtualizes physical block storage devices

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The State of Data Storage

• A Snapshot of Where We Are Today
• Data Tsunami Continues
• Data Scattered across data centers and remote
  locations
• Stringent Compliance And Regulatory Environment
• Data Protection is at a break point
• Cant add IT staff indiscriminately to keep up
  with capacity growth
• Storage management tools are archaic
• Storage tiers still infancy. Data is not mobile.

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Typical SAN Today
Server 1
Server 2
Server 3
Server 4
V1
V4
V2
V3
V5
SAN
V1
V3
V2
V5
V4
Ultimate Vision of SAN is Incomplete
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Why Storage Virtualization is En Vogue Again

• Heterogeneous Storage is a Reality
• Data Migration, Data Consolidation are Disruptive
  Processes Today
• V has Passed the Hype and Low Point Stages
  and into Reality Stage
• Big guys have Ratified the Concept (IBM, EMC, HDS)

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What is Storage Virtualization?

• Separation of Physical and Logical
• Enables One Common Set of Applications
• Physical can be Heterogeneous or Homogeneous
• Underwear

RAID equals elemental storage virtualization
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Heterogeneous Homogeneous Virtualization
Common Storage Applications
Virtualization Layer
EMC
EMC
HDS
JBOD
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What Does Storage Virtualization Enable?

• Consistent Interface for All Storage Applications
• Non-disruptive LUN Creation, Expansion, Deletion
• Non-disruptive Data Consolidation, Data Migration
• Non-disruptive RAID Level Changes
• Tiering of Storage Using Hetero Storage
• Replication Across Hetero Storage
• Backup/Restore, Archival, Thin Provisioning, etc.

Storage Virtualization Completes SAN Vision
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Where Can It Be Done?
Host-based Volume Management
SAN
Appliance
Intelligent Switch
Purpose Built Appliance (PBA)
Network-based Virtualization
Controller-based Virtualization
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Types of Network-based Solutions

• Intel-based platforms (Appliance)
• Simple and cost-effective form factor
• Most widely deployed approach to date
• Rich set of advanced storage applications
  available
• Examples IBM SVC, DataCore, FalconStor
• Purpose-built appliances (PBA)
• Strong interoperability support in heterogeneous
  environments
• Support for multiple storage applications
• Designed for mid-range to mission-critical apps
• Require two management interfaces
• Examples QLogic/Troika

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Types of Network-based Solutions Continued

• Intelligent Switches
• Promises highest levels of scalability,
  availability, and performance
• Data-center ready design
• Virtualization controller software unproven
  lack key storage applications
• Relatively higher cost per port
• Switch Examples Brocade, Cisco, McData
• Virtualization Controller Examples EMC InVista,
  Incipient, StoreAge

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Fundamental Concepts

• Metadata Server
• Maintains Configuration Database
• Virtualization Mapping Tables
• Control Path Software
• Provides Interface Between Metadata Server and
  Data Path Server
• Performs Background I/O Tasks
• Data Path Software
• Moves Data from Server to Storage (and vice
  versa)
• Performs Translation from Virtual to Physical
  Addresses

Note Datapath Software is Always in the Data Path
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Virtualization Architectures In-Band vs.
Out-of-Band

• In-Band
• Data and Control Data are managed by same compute
  elements
• Initial implementations lacked scalability and
  performance
• Newer implementations much more scalable and
  enterprise-class
• Examples IBM SVC, FalconStor
• Out-of-Band
• Separates data and control paths
• Requires host agents creating management
  complexity and potential for security breaches
• Example StoreAge

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Virtualization Architectures Split Path
Architecture for Intelligent Devices (SPAID)

• Hybrid of In-Band Out-of-Band Approaches
• Separates control path from the data path
• Leverages port-level processing capabilities of
  intelligent switches or purpose-built controllers
• Unproven approach given the lack of availability
  of intelligent switches (holds highest potential)
• Example EMC InVista, Incipient, StoreAge

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SPAID Architecture
Hosts

• Split Path Architecture
• Most I/O are routed through the Fast Path at near
  line speeds on purpose-built ASICs
• Few I/Os are faulted to the Control Path (CP)
• No state / no cache
• Full fabric bandwidth
• Scalable across entire fabric

Intelligent FC Switch
Fabric A
Fabric B
Arrays
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Players and Strategy

• IBM (SVC on Appliance)
• EMC (InVista on Intelligent Switches)
• Incipient (Incipient on Intelligent Switches)
• HDS (Internal Controller)
• QLogic/Troika (PBA via Partnerships with Software
  Vendors)
• StoreAge (Out of band Appliance or Intelligent
  Switch)
• FalconStor (Appliance)
• Cloverleaf (Appliance)
• Cisco, Brocade/McData (Intelligent Switches via
  Partnerships)

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File System Virtualization

• Abstraction of logical relationships above
  individual file system image
• Separates user and group relationships from
  specific devices
• Enables creation of exports and shares

Creates a global namespace
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Server Virtualization Storage

• Server virtualization presents unique challenges
  for storage
• Much higher SAN attach rate than traditional
  applications
• Shared storage CLVM is common deployment for VM
  mobility (e.g. VMotion Live Migration)
• HBAs must be specifically qualified to run at
  hypervisor level for VMWare
• Single HBA shared across all virtualized guest
  OSes

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Server Virtualization Virtual HBAs

• Enables HBAs to be virtualized using
  industry-standard N-Port ID Virtualization (NPIV)
• Enables SAN best practices, standard management
  tools in a virtualized environment
• Examples Fabric zoning, Array-based LUN masking

Example Emulex
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Network I/O Virtualization

• IO Virtualization
• Quickly map and re-map server and storage
  configuration (e.g. MAC WWN identifiers, boot
  images, etc) so that applications can be
  provisioned and re-provisioned without changes to
  fabric or servers.
• Step toward virtual data center and stateless
  servers that change personality based on demand
• Ex. HP Virtual Connect, Cisco VFrame, Voltaire
  GridVision

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Recommendations to Users

• If Mostly Homogeneous, virtualization is still
  important.
• Stay with existing vendors virtualization
  solution.
• If Highly Heterogeneous, go with intelligent
  switch, PBA, or appliance
• Ensure the Applications you want are Available
• Be Wary of Internal Controller Approaches
• Ensure Solution is Not All or Nothing

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Questions
?

• Arun Taneja
• ArunT_at_tanejagroup.com