Preparing a Volume to Restore From Backup

Create a snapshot mirror of the volume to be backed up.

The vxassist snapstart task creates a write-only backup mirror, which is attached to and synchronized with the volume to be backed up. When synchronized with the volume, the backup mirror is ready to be used as a snapshot mirror. However, it continues being updated until it is detached during the actual snapshot portion of the procedure. This may take some time, depending on the volume size.

To create a snapshot mirror for a volume, use the following command:

	
	# vxassist snapstart volume_name

For example. to create a snapshot mirror of a volume called voldef, use the following command:

		# vxassist snapstart voldef 

Choose a suitable time to create a snapshot volume.

If possible, plan to take the snapshot at a time when users are accessing the volume as little as possible.

Create a snapshot volume that reflects the original volume at the time of the snapshot.

The online backup procedure is completed by running the vxassist snapshot command on the volume with the snapshot mirror. This task detaches the finished snapshot mirror, creates a new normal volume, and attaches the snapshot mirror to it. The snapshot then becomes a read-only volume. This step should only take a few minutes.

To create a snapshot volume, use the following command:

		# vxassist snapshot volume_name new_volume_name

For example, to create a snapshot volume of voldef, use the following command:

		# vxassist snapshot voldef snapvol

The snapshot volume can now be used by backup utilities, while the original volume continues to be available for applications and users.