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The backup image command creates an image backup of one or more volumes on your system. These volumes can be formatted FAT, FAT32, NTFS, or unformatted RAW volumes. If a volume is NTFS-formatted, only those blocks used by the file system will be backed up. If you set the imagapsize option to 0, all blocks, including unused blocks at the end of the volume, will be backed up. See Imagegapsize for more information.
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 traditional offline image backup prevents access to the volume by other system applications during the operation.
If the LVSA is installed and configured, Tivoli Storage Manager performs an online image backup during which the volume is available to other system applications. See Performing an Image Backup (Windows 2000 Only) for information on how to install and configure the LVSA.
You can use the imagetype option with the backup image command or the include.image option to specify whether to perform an offline or online image backup. See Imagetype for more information.
During an online image backup, the following occurs:
You can use the following options to control an online image backup:
The following considerations apply to offline and online image backups:
The Windows 2000 client supports SAN-based server-free data movement that off-loads data movement processing from the client and server processor and from the LAN during image backup and restore operations. Data is transferred directly between client disks and SAN-attached storage devices by a third-party copy function initiated by the Tivoli Storage Manager server. Tivoli Storage Manager will not compress or encrypt data during sever-free image backup.
If SAN errors occur, the client fails-over to a direct connection to the server or a connection to the storage agent and proceeds to move data via LAN-free or LAN-based data movement. When server-free data movement fails-over to LAN-free or LAN-based data movement, the data will not be compressed, even if you set the compression option to yes, to allow for a subsequent server-free restore of the image.
To enable SAN-based server-free support, the Tivoli Storage Manager Managed System for SAN feature must be installed and configured on the Tivoli Storage Manager Windows server. For an overview of the SAN-based server-free backup, see Appendix B, SAN-Based Server-Free Image Backup.
After the Tivoli Storage Manager Managed System for SAN feature is installed and configured on the Tivoli Storage Manager Windows server, use the enableserverfree option in your dsm.opt file. See Enableserverfree for more information.
When performing a server-free image backup, you must bind the volume to a management class that has a nonblocked destination storage pool; server-free paths must exist between all of the client disk(s), data mover, and storage pool. For more information, refer to Tivoli Storage Manager for Windows Administrator's Guide, GC32-0782.
The client can perform an offline or online image backup. If the LVSA is installed, the client performs an online volume image backup, allowing access to the volume by other system applications during the operation. See Offline and Online Image Backup for more information about options you should use to perform online image backups, and considerations that apply to online image backups.
Server-free backup is only available for NTFS-formatted volumes and raw volumes; FAT and FAT32 file systems are not supported. The following volume types are supported:
When using the backup image command, it is important to be aware of special considerations if you want to do either of the following:
To ensure that you can perform point-in-time restores of your file systems, including deleting original files which no longer exist on the logical volume, use a combination of full image backups and the incremental command as described in the steps below:
dsmc incremental h:
dsmc backup image h:
dsmc incremental h:
You must follow these steps in the order shown to ensure that the server records additions and deletions accurately. The following command restores the file system to its exact state as of the last incremental backup:
dsmc restore image h: -incre -del
If you do not follow the steps exactly, two things can occur:
Two types of backup apply to logical volumes: mode=selective (the default) and mode=incremental. The mode=selective option creates and sends a full backup copy of the logical volume to the server. The mode=incremental option sends only those files that were added or changed since the last full image backup to the server. Tivoli Storage Manager ignores the -deletefiles option when the image+image incremental technique of backing up has been used.
If you use the backup image command, first with mode=selective followed by one or more executions with mode=incremental, use the incremental option with the restore image command to apply any changes made after the original image backup. The restore may include files that were later deleted plus the latest versions of files added or changed after the original image backup. If logical volumes are running at or near capacity, an out-of-space condition could result during the restore. For more information, see "Incremental-by-Date". The deletefiles option is allowed on the restore image command, but the client ignores it because the server is not aware of any deleted files.
The following restrictions apply:
Supported Clients
This command is valid for Windows 2000 only.
Syntax
.-----------------. V | >>-Backup Image--+----------+----+-------------+-+------------->< '- options-' +- filespec---+ '- "filespec"-'
Parameters
You can also use these common options: domain.image, exclude.image, include.image, imagegapsize, postsnapshotcmd, presnapshotcmd, snapshotcachelocation, snapshotfsidleretries, snapshotfsidlewait, snapshotcachesize. For information, see Chapter 9, Setting Processing Options.
Examples
Command: dsmc backup image m:\mnt\myntfs
Command: dsmc backup image h: -mode=incremental
Command: dsmc backup image f: -imagetype=static
Command: dsmc backup image f: