Backup Image

You can use the backup image command to back up NTFS or ReFS, or unformatted RAW volumes. If a volume is NTFS-formatted, only those blocks that are used by the file system are backed up. On ReFS volumes, all blocks are backed up.

If you set the imagegapsize option to 0, all blocks, including unused blocks at the end of the volume, are backed up.

If you specify an AIX® JFS2 file system for image backup, only those blocks that are used by the file system are backed up. If you set the imagegapsize option to zero, all blocks, including blocks at the end of the volume, are backed up.

Note:

1. AIX only: By default, snapshot-based image backup is enabled for JFS2 volumes. To turn off snapshot-based image backups, set -snapshotproviderimage=NONE on this command.
2. For the Linux clients, image backup is only supported on partitions with id 0x83 or logical volumes that are created with the Linux Logical Volume Manager. Backing up other partitions, such as extended partitions that contain mounted file systems or database data, can produce inconsistent backup data if the data changes during the image backup operation.
3. Backup image is not supported on any GPFS™ file system.
4. The Tivoli® Storage Manager API must be installed to use the backup image command.
5. When you change the attribute of a JFS2 file system to an HSM-managed file system, an image backup is not done for that file system.

Important: The last incremental backup time refers to the server time and the file modification time refers to the client time. If the client and server time are not synchronized, or the client and server are in different time zones, this affects incremental-by-date backup and image backup where mode=incremental.

The client backs up the files that have modification dates and times (on the client) that are later than the date and time of the last incremental backup of the file system on which the file is stored (on the server).

If the server time is ahead of the client time, incremental-by-date backups, or image backup with mode=incremental, skip the files, which had been created or modified after the last incremental or image backup with a modification date earlier than the last incremental backup time stamp.

If the client time is ahead of the server time, all files that had been created or modified before the last incremental or image backup and have a modification time stamp later than the last incremental backup time stamp, are backed up again. Typically, these files would not get backed up because they had already been backed up.

The backup date can be checked by the query filespace command.

Note:

1. The account that is running the Tivoli Storage Manager client must have administrator authority to successfully perform any type of image backup.
2. The API must be installed to use the backup image command.

The Tivoli Storage Manager client must support the raw device type on the specific platform to perform an image backup of a raw device. You can perform an image backup only on local devices. Clustered devices or file systems as well as devices or file systems that are shared between two or more systems are not supported. If you want to perform an image backup for a file system that is mounted on a raw device, the raw device must be supported.

Use the include.image option to include a file system or logical volume for image backup, or to specify volume-specific options for image backup.

The backup image command uses the compression option.

Supported Clients

This command is valid for AIX, HP-UX, all Linux clients, and Solaris.

This command is valid for all Windows platforms.

Parameters

filespec

Specifies the name of one or more logical volumes. If you want to back up more than one file system, separate their names with spaces. Do not use pattern matching characters. If you do not specify a volume name, the logical volumes that are specified with the domain.image option are processed. If you do not use the domain.image option to specify file systems to process, an error message is displayed and no image backup occurs.

Specify the file space over which the logical volume is mounted or the logical volume name. If there is a file system that is configured in the system for a given volume, you cannot back up the volume with the device name.

For example, if the /dev/lv01 file space is mounted on the /home volume, you can issue backup image /home, but backup image /dev/lv01 fails with an error:

ANS1063E Invalid path specified

Note: For Sun systems, specify either a file system name or a raw device name (block device type).

Image backup is only supported on a volume that has a mount or a drive letter assigned to it. A volume without a drive letter or mount point cannot be backed up.

Table 1. Backup Image command: Related options

Option	Where to use
asnodename	Client options file (dsm.opt) or command line.
asnodename	Client system options file (dsm.sys) or command line.
compressalways	Client system options file (dsm.sys) or command line.
compressalways	Client options file (dsm.opt) or command line.
compression	Client options file or command line.
dynamicimage	Use with the backup image command or the include.image option in the options file.
imagegapsize	Use with the backup image command, the include.image option, or in the options file.
mode	Command line only.
postsnapshotcmd	Use with the backup image command, the include.image option, or in the options file.
presnapshotcmd	Use with the backup image command, the include.image option, or in the options file.
snapshotcachesize	Use with the backup image command, the include.image option, or in the options file.
snapshotproviderimage	Client options file or with include.image option.