Backing up Solaris Zettabyte file systems

On Solaris SPARC and Solaris x86 systems, you can backup Zettabyte file systems (ZFS), by using ZFS snapshots. The advantage of this approach, over an ordinary incremental or selective backup, is that the files and folders in a snapshot are always in a read-only state, so they cannot be changed during a backup.

About this task

You create a ZFS snapshot by using Oracle Solaris ZFS commands. For example:

zfs snapshot tank/myZFS@mySnapshot

In this example, the ZFS pool name is called tank and the ZFS file system name is myZFS. Files that belong to this ZFS snapshot are in the subdirectory named tank/myZFS/.zfs/snapshot/mySnapshot/.

Procedure

Use either of these two methods to backup a ZFS snapshot.

Backup each file of the snapshot by using the snapshotroot option. For example:
```
dsmc inc -snapshotroot=/tank/myZFS/.zfs/snapshot/mySnapshot /tank/myZFS
```
This option allows the administrator to replace the current snapshot path with the ZFS file system path, so that the files and folders are backed up under the original file system.
Backup the complete snapshot by using Oracle Solaris ZFS commands. For example:
```
zfs send tank/myZFS@mySnapshot > /tmpdir/mySnapshotFile
```
The advantage of backing up the complete snapshot is that the full file system can be restored, in a disaster recovery scenario.