CCDP SAN Design Considerations - Study Notes - Part 1

    SAN Design Considerations - Study Notes - Part 1

     

    Main Concepts

     

    DAS - Direct Attached Storage

     

    NAS - Network Attached Storage (access via NFS, CIFS)

     

    SAN - Storage Area Network (scsi technologies and fibre channel)

     

    Fabric

     

    HBA - Host Bus Adapter

     

    Initiator

     

    Zone

     

    VSAN

     

    Cisco Storage Virtualization

     

    - Available logical space for data storage.

     

    - The SAN system handles the process of mappig to an actual physical device.

     

    - MDS 9000 family ==> VSANs capable

     

    - Trunking between VLANs ==> ISL and Enhanced ISL

     

    Inter-VSAN Routing

     

    - IVR is fabric routing

     

    - Sharing of centralized storage services across VSANs

     

    - Fabric Shortest Path First

     

    - Topology database

     

    - Dynamic Incremental SPF

     

    - Associates a cost with each link

     

    Zoning

     

    - Logical grouping of fabric devices within SAN or VSAN

     

    - Soft Zoning (using DNS) or Hard Zoning (equipment built in).

     

     

    FICON - Technology

     

    - Fiber connectiviy invented by IBM

     

    - Connects mainframes to SAN

     

    - Cisco supports FICON and FCP (Fibre Channel Protocol).

     

     

    SANTap - Technology

     

    - Protocol that allows third party storage application to be integrated into the SAN.

     

    - Replicates the data simultanously.

     

    Design Concerns

     

    - Port density.

     

    - Topology

     

    - Oversubscription

     

    - Traffic Management ==> different performance requirements should be handled using techniques

     

    - Fault Isoltation ==> using VSAN

     

    - Convergence and Stability

     

     

    SAN Design

     

    - Collapse core.

     

    - Dual Fabric collapse core

     

    SAN Extension

     

    - Remote connectivity between different SAN networks using protocols like FCIP and iSCSI.

     

    - FCIP: fiber channel over IP ==> any distance

     

    - iSCSI: SCSI over IP

     

    - Several enhancements: data compression and write acceleration