Xsan Configuration Files
Xsan stores its configuration information in the following files.
Note: Don’t edit these files except under the direction of an Apple support engineer.
File or folder in /Library/Filesystems/Xsan/
Additional volume settings used by Xsan Admin
Volume autostart list
Xsan volumes to be mounted during startup,
and their mount options
Private Xsan Admin configuration information
Notification settings made with Xsan Admin
Note files whose contents were entered in Xsan
Admin’s Inspector window
Private Xsan Admin computer identification
affinity A relationship between a folder on an Xsan volume and one or more storage
pools that provide storage for the volume. The affinity guarantees that files placed in
the folder are stored only on the associated storage pools. Storage pools can differ in
capacity and performance, and affinities can be used to assure that data such as video,
which requires high transfer speed, is stored on the fastest storage devices.
affinity tag In Xsan predefined volume types, you assign LUNs to affinity tags
instead of assigning the LUNs directly to storage pools. Then Xsan Admin can create
underlying storage pools with appropriate affinities and the optimal numbers of LUNs
to achieve best performance.
allocation strategy In Xsan, the order in which data is written to the storage pools
that make up a volume. Applicable only if there’s more than one storage pool in
a volume, and only if the pools are of the same class. Can be fill, round robin, or
balance An Xsan storage pool allocation strategy. Before allocating space on a volume
consisting of more than one storage pool, Xsan checks available storage on all pools,
and then uses the one with the most free space.
block allocation size An Xsan volume property. The smallest number of bytes that can
be reserved on, written to, or read from an Xsan volume.
client A computer (or a user of the computer) that requests data or services from
another computer, or server.
controller In an Xsan storage area network, short for metadata controller. In RAID
systems, controller refers to hardware that manages the reading and writing of data.
By segmenting and writing or reading data on multiple drives simultaneously,
the RAID controller achieves fast and highly efficient storage and access. See also
failover In Xsan, the automatic process by which a standby metadata controller
becomes the active metadata controller if the primary controller fails.
failover priority On a SAN with more than one controller, specifies which standby
controller to try first during failover.