Oracle Solaris ZFS Administration Guide

Creating a ZFS Storage Pool With Log Devices

By default, the ZIL is allocated from blocks within the main pool. However, better performance might be possible by using separate intent log devices, such as NVRAM or a dedicated disk. For more information about ZFS log devices, see Setting Up Separate ZFS Log Devices.

You can set up a ZFS log device when the storage pool is created or after the pool is created.

The following example shows how to create a mirrored storage pool with mirrored log devices:

# zpool create datap mirror c1t1d0 c1t2d0 mirror c1t3d0 c1t4d0 log mirror c1t5d0 c1t8d0
# zpool status datap
  pool: datap
 state: ONLINE
 scrub: none requested

        NAME        STATE     READ WRITE CKSUM
        datap       ONLINE       0     0     0
          mirror-0  ONLINE       0     0     0
            c1t1d0  ONLINE       0     0     0
            c1t2d0  ONLINE       0     0     0
          mirror-1  ONLINE       0     0     0
            c1t3d0  ONLINE       0     0     0
            c1t4d0  ONLINE       0     0     0
          mirror-2  ONLINE       0     0     0
            c1t5d0  ONLINE       0     0     0
            c1t8d0  ONLINE       0     0     0

errors: No known data errors

For information about recovering from a log device failure, see Example 11–2.