




If the Tivoli® Storage Manager image feature is configured, you can create an image backup where the real volume is available to other system applications.
A consistent image of the volume is maintained during the image backup.
When you perform an image
backup using the client GUI image backup option, Tivoli Storage Manager honors
the snapshotproviderimage setting in your client
options file (dsm.opt). If the Tivoli Storage
Manager online image support is configured, Tivoli Storage Manager performs an online
image backup, during which the volume is available to other system
applications.

When you perform an image backup using the client Java™ GUI image backup option, Tivoli Storage Manager honors
the setting of the snapshotproviderimage option.
The snapshotproviderimage option defaults to an AIX® JFS2 snapshot for AIX and a Linux LVM
snapshot for Linux. You can
override the default by using the Preferences editor Snapshot tab
and the Image Snapshot Preferences.

For
HP-UX and Solaris clients, selecting the image backup option
performs a static image backup by default. For static image backup,
the client unmounts and remounts the volume as read-only, so that
no other applications can access it. You can override the default
value by using the include.image option and selecting dynamicimage yes.
For dynamic image backup, the client performs the image backup without
making the file system read-only during the backup.
To create an image backup of your file system or raw logical volume, perform the following steps:



To perform a static image backup,
select Image Backup from the drop-down list.
To perform an offline image backup, select Image
Backup from the drop-down list.
To perform an online image backup, select Snapshot
Image Backup from the drop-down list. 
For AIX and Linux clients only: To
perform a snapshot image backup, use the snapshotproviderimage option.


The following are some
items to consider when you perform an snapshot-based image backup:
The following are some items to consider when you
perform an online image backup:
Because image backup allows you to back up
only used blocks in a file system, the stored image size on the Tivoli Storage Manager server
could be smaller than the volume size. For online image backups, the
stored image can be larger than the file system based on the size
of the cache files. To determine the actual stored image size, select View → File
Details. The actual stored image size is noted in the Stored Size
field.
Because image backup allows you to back up
only used blocks in a file system, the stored image size on the Tivoli Storage Manager server
could be smaller than the volume size. For online image backups, the
stored image can be larger than the file system based on the size
of the cache files. To determine the actual stored image size, select View → File
Details. The actual stored image size is noted in the Stored Size
field.
Linux only: The Tivoli Storage Manager Version
5.4 (and newer) client will not recognize any LVM1 volumes for image
operations. However, it allows prior image backups of LVM1 volumes
to be restored on LVM2 volumes. Table 1 shows
the combinations involving the old and new client levels handling
LVM1 and LVM2 volumes for different image operations.

| Tivoli Storage Manager client version | LVM1 Backup and Restore | LVM2 Backup and Restore | Mixed Volumes | |
|---|---|---|---|---|
| Backup: LVM1, Restore: LVM2 | Backup: LVM2, Restore: LVM1 | |||
| V5.3 and prior | YES | Only static image for file system | NO | NO - raw volumes are not supported |
| V5.4 and beyond | NO |
YES | YES |
NO |