Xsan Components: 17

A list and description of supported components of the Xsan

Client

•  Typically this is a regular Apple G5 or Intel Apple.
• Also possible is a Windows PC/Server using the right StorNext FX SAN client. (See also Apple KB # 303222).

Metadata Controller (MDC)

• This is usually an Apple Xserve but can also be a regular G5 or Mac Pro.

Storage

• Usually an Apple Xserve Raid.
• Some users have built very stable and fast Xsans on 3rd party storage.

Ethernet Network

• It is highly recommended you have a separate ethernet network that doesn't access the internet or use any services, this network is strictly for the Xsan metadata. The most simple GBit ethernet switch is ok, the simpler the better. (this has to do with the latency in the more advanced Ethernet switches).
• The Metadata network should be below the main network in the service order, this is because OS X likes to chatter a lot over the primary network (itunes looking for shared music etc).  If OS X was allowed to chatter on the metadata network it would increase the latency and thus decrease xsan performance.
• Tiger - Open the Network pane within System Preferences select 'Network Port Configurations', and drag the network you wish to be the primary connection to the top of the list.  The metadata network should sit just below.
• Leopard - Open the Network pane within System Preferences, click the small cog at the bottom left corner and select 'Set Service Order...'.  In the pop-up window place the primary network at the top of the list and the metadata network just below.

Fibre Channel Network

• All of your clients and metatdata controllers will communicate with the storage over fibre

Xsan Software

• Xsan requires every client and every MDC to have a license.
• The pricing of the StorNext FX is a bit higher than Xsan. And is only a client license. It is not possible to use the StorNext FX as a MDC.

Uninterruptible Power Supply/Condition

• XServe Servers, MDC's, switches, monitors, etc do not have batteries included. So good back up power supply is  an essential component of a well designed system.
• Is there enough power? Is a question often overlooked. If you take into account that a XServe Intel has a power-consumption of max 4A on 240 V, and max 8A on 110 to 120 V. So add a couple of XServe's and all the rest of the hardware needed, make sure that the power-consumption groups do have enough Amps available to power the setup on... Or you will be in for a surprise!
• So make sure that the UPS is capable to power the components.

Air Conditioning!  All those drive, servers and switches throw off a lot of heat.

• Often overlooked, air conditioning is crucial to the health and longevity of the  drives.
• Most X-SAN's are on 24/7. Does your AC run 24/7?   Many offices use "economy modes" which kill the AC after hours and on weekends.  This can also kill your X-SAN.