Definitions

• SAN – Storage Area Network
• NAS – Network Attached Storage
• DAS – Direct Attached Storage
• SCSI – Small Computer Storage Interconnect (Interface?)
• FC – Fiber Channel Protocol
• FC – Fibre Channel light pipe cabling
• iSCSI – IP based SCSI communication
• TCP – Transmission Control Protocol/Internet Protocol
• LAN – Local Area Network
• ROI – Return on Investment
• TCO – Total Cost of Ownership
• PBP – Pay Bay Period
• CDP – Continuous Data Protection
• IB – Infiniband
• Backup window – time it takes to back up data
• Server Clustering – method of making two or more servers appear as one
• DNS – Domain Name Servers
• WINS – Windows Internet Naming Servers
• DC – Domain Controllers

• HBA – Host Bus Adapter
• GBIC – Gigabit Interface Controller
• RAID – Redundant Array of Inexpensive (Independent) Disks
• JBOD – Just a Bunch Of Disks
• Storage Array – hardware/firmware combo
• Storage Network Industry Alliance
• GLM – Gigabit Link Module
• SAS – Serial Attached SCSI
• SATA – Serial ATA

 

 

• Layers

• Physical Layers
• Software Layers

• Protocol stack

• TCP/IP v.s. FC

• TCP/IP protocol with Ethernet (Files)
• FC protocol with FC Switches (Data)

• Functions

• LAN – move files
• SAN – direct access to hardware

• 4 P’s

• Parts
• Protocols
• Players
• Platforms

• Parts

• Host Layer/Fabric Layer/Storage Layer
• Host Layer

• HBA – Host Bus Adapter

• Plugs into server itself
• Interfaces between software and hardware

• Gigabit Interface Controller

• This port is present at EVERY connection point in the FC network
• Houses laster and electronics that convert data from/to light/electronic pulses
• Interfaces between FC protocol and HBA for block access

• Fiber Optic Cable

• Used as interconnect
• 3 types, based on wavelength employed in the FC network

• Fabric Layer

• Middle layer of a SAN
• Hub

• (only one devices talks at a time) creates loop, thus SAN loop

• Switch

• Smart device that routes information to SPECIFIC destination

• Gateway/Bridge

• Converts data to/from differing protocols
• iSCSI to FC

• Router

• Moves data from separate networks

• Storage Layer

• All data exists here
• Disk drives, Tape drives, optical storage
• RAID/JBOD arrays
• Storage Array – big box of disks running smart code(firmware) for managing disks

• Modular

• Smaller unit with computer memory for caching data from slower disks
• Fewer port connections
• Upgrade via

• Shelves of 10-16 disks
• Plug-in controllers for more throughput

• Controllers usually are mirrored and have 16-32G memory
•  

• Monolithic

• Huge machine with 100s of Gigs of memory
• Many port connections
• Hundreds of disks
• Shared GLOBAL memory
•  

• SAN Protocols

• Fibre Channel

• Low-level protocol between disks and host applications
• FC-AL (Fibre Channel – Arbitrated Loop) [HUBS]
• FC-SW (Fibre Channel – Switched ) [SWITCHES]
• Fibre Channel provides a pipe for SCSI to work within
•  

• SCSI

• Works on top of FC

• iSCSI over IP

• Infiniband iSER and SRP

• Platforms

• Olders OS’s such as Windows NT don’t support SAN
• Big, fast servers with Intel/AMD do
• Unix machines
• Mainframes
• 

SAN Building Blocks

• Host Layer

• HBA
• HBA Drivers
• GBIC
• Cables
• Host Bus Adapter

• Hardware and BIOS firmware that works between OS and Disks

• GBICs and GLMs

• Shortwave

• .5 meters and 500 meters
• 780 nm and 850 nm
•  

• Longwave

• 2m to 10km
• 1300nm and

• Each GLM has 2 connections, IN and OUT (FULL DUPLEX)
• Full  Duplex allows for simultaneous comm IN/OUT
• Each FC cable has 2 thin pieces of glass for this purpose

• SC

• Original connectors used in SANs
• 1Gps

• LC

• Smaller 2nd generation
• 2,4,8,10Gps

 

• Fabric Layer

• Fabric Layer – hardware in SAN, specifically FC components
• Storage Fabric – set of organized, connected storage devices on a network of interconnected switches that can be accessed by servers (up to 239)
• Switched Fabric – consists of all switches in a single storage fabric
• SAN Fabric – consists of all the individual switched  fabrics in the SAN
• SANs can have more than one SAN fabric

• Usually two are present for redundancy
• When switches are not connected together, they constitute individual fabrics each with their own fabric ID in each switch
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