Apple Xsan 1.0 - Manual (Page 43)

Chapter 3 Managing SAN Storage 43
Adding LUNs to a Storage Pool
You can increase the capacity of a SAN volume by adding LUNs (RAID arrays or array
slices) to a storage pool that belongs to the volume.
Choosing Compatible LUNs
Add LUNs that are similar in performance and capacity to the LUNs already in the
storage pool. Mixing LUNs of different sizes or speeds in the same storage pool can
degrade performance and waste capacity.
Note: A storage pool can’t contain more than 32 LUNs and the total number of LUNs in
a volume can’t be greater than 512.
To add a LUN to a storage pool:
1 If you’re adding an Xserve RAID system to host the array, connect it to the SAN’s Fibre
Channel and Ethernet networks.
2 If you haven’t already done so, use RAID Admin to create the RAID array or slice. For
help, see Using RAID Admin and Disk Utility (available at
www.apple.com/server/documentation) or look in the RAID Admin online help.
Note: Don’t use Disk Utility to format the new array. You’ll use Xsan Admin to format
the array for Xsan in Step 6.
3 Open Xsan Admin and select the SAN in the SAN Components list.
4 Click Setup, then click LUNs.
5 Select the new array or slice in the list of available LUNs and click Edit.
6 In the dialog that appears, type a label for the LUN, click OK, and click Save.
The label can’t contain spaces. Only SAN administrators, not users, will see this label.
7 Click Storage, then click Available LUNs.
8 Drag the new LUN to make it the last LUN in the storage pool and click Save.
If the new LUN is not the same size as the existing LUNs, the usable size is shown next
to the LUN in the list.
9 Select the volume in the SAN Components list, click Clients, and unmount and remount
the volume on each client that has it mounted.
Note: To have an existing file redistributed across all of the LUNs in the storage pool
(including the LUN you just added), you must make a new copy of the file. If you are
adding LUNs to speed up access to a file, be sure to duplicate the file so a new copy is
distributed across all available LUNs.
LL0192.book Page 43 Thursday, July 29, 2004 5:20 PM