How to Hook Up a SAN?

A storage area network is directly attached to the system and controlled by an integrated processor and software designed to enhance users’ productivity. Installing a SAN is a great way to increase any enterprise network’s storage capacity without upgrading or replacing servers or other equipment.

Options for SAN connectivity are

  • TCP/IP
  • WAN
  • Fibre Channel
  • iSCSI
  • FCoE

Basic Options for connectivity:

Fibre Channel [FC]: The older and dedicated solution.

iSCSI [ Pronounce iScuzzy ] .

  • Built to handle storage traffic. Always expensive and requires purchasing dedicated switches.
  • iSCSI refers to using ethernet network switches and infrastructure to connect servers to your SAN.
  • iSCSI still lags behind FC’s performance potential and inherently places more demands on your server’s processor. This is because of the need to run on top of TCP/IP protocols and requiring the server’s processor to generate storage commands. However, when implemented properly with 10Gbps Ethernet links on over-provisioned servers the difference is almost negligible. 10Gbps ethernet cabling and switches are not cheap either.
  • For small businesses with low demand, even using 1Gbps cabling can be a cheap and easy solution to setting up a SAN. It is just going to be slower.

FCoE (Fibre Channel over Ethernet) is the latest.

  • Like iSCSI, it runs over multipurpose ethernet infrastructure.
  • FCoE uses its own protocol, rather than sitting on top of TCP/IP.
  • Basically, it generates less code and is therefore faster.
  • It can’t be routed over WAN – requiring a bridge to connect remote locations.

FCoIP (Fibre Channel over IP)

  • Used in a limited capacity to cheaply link FC SANs across multiple locations using a TCP/IP network.
  • Never used as a local system because of high latency.

What Infrastructure Choice is Best for Your SAN?

Looking Positive Side:

  • FCoE is the complicating factor in decision making.
  • iSCSI has generally be considered the cheaper and more accessible option for small businesses
  • FC has been the premium enterprise solution.
  • The growing prevalence of 10Gbps ethernet cables are somewhat nullifying the need to invest in FC for all but the most I/O heavy environments.

Conversely:

The flexibility of FCoE is undermining the cost benefits of using iSCSI. The problems with FCoE are mostly centred on expertise.

  1. FCoE uses many of the same specialised management tools as FC that may be unfamiliar to those not already operating FC infrastructure.
  2. Extending your FC network with FCoE requires extra steps to connect the different types of physical infrastructure.
  3. FC still remains the premium solution – but, creative use of iSCSI and FCoE are certainly viable and cheaper options.
  4. FCoE over 10Gbps ethernet will be best bet for many businesses in future.
  • Fibre Channel is the dedicated and premium solution
  • iSCSI has become increasingly accessible and powerful as higher performance ethernet cabling has entered the market
  • FCoE is the newcomer that looks likely to swing the balance in favour of existing 10Gbps ethernet infrastructure.