Recommendations for State Database Replicas

• You should create state database replicas on a dedicated slice of at least 4 Mbytes per replica. If necessary, you could create state database replicas on a slice that will be used as part of a RAID 0, RAID 1, or RAID 5 volume, soft partitions, or transactional (master or log) volumes. You must create the replicas before you add the slice to the volume. Solaris Volume Manager reserves the starting part of the slice for the state database replica.

• You can create state database replicas on slices that are not in use.

• You cannot create state database replicas on existing file systems, or the root (/), /usr, and swap file systems. If necessary, you can create a new slice (provided a slice name is available) by allocating space from swap and then put state database replicas on that new slice.

• A minimum of 3 state database replicas are recommended, up to a maximum of 50 replicas per Solaris Volume Manager disk set. The following guidelines are recommended:

  • For a system with only a single drive: put all three replicas in one slice.

  • For a system with two to four drives: put two replicas on each drive.

  • For a system with five or more drives: put one replica on each drive.

• If you have a RAID 1 volume that will be used for small-sized random I/O (as in for a database), be sure that you have at least two extra replicas per RAID 1 volume on slices (and preferably disks and controllers)that are unconnected to the RAID 1 volume for best performance.