Cache device requirements
Note the following:
The cache device is a raw disk partition: either a logical volume or physical disk. The cache is used for storing the portions of the client's data that incoming write requests change while the copy-on-write is in progress.
For the cache device, do not select an active partition containing valuable data. Any data in that partition is lost when the snapshot is complete.
Warning:
Choose a cache partition carefully! The cache partition's contents are overwritten by the snapshot process.
Specify the raw partition as the full path name of either the character special device file or the block device file. For example:
Solaris raw partition:
/dev/rdsk/c2t0d3s3
Or
/dev/dsk/c2t0d3s3
VxVM volume:
/dev/vx/rdsk/diskgroup_1/volume_3
Or
/dev/vx/dsk/diskgroup_1/volume_3
Note:
Do not specify wildcards (such as /dev/rdsk/c2*) as paths.
The cache partition must be unmounted.
The cache partition must reside on the same host as the snapshot source (the client's data to back up).
The partition must have enough space to hold all the writes to the partition that may occur during the backup. Note that backups during off-peak periods normally require a smaller cache than a backup during peak activity.
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