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The incremental command backs up all new or changed files or directories in the default client domain or from file systems, directories, or files you specify, unless you exclude them from backup services.
To incrementally back up selected files or directories, enter a file specification in the command. If you do not enter a file specification, the default is to back up files or directories in the default domain.
The following attributes in the management class assigned to the file or directory affect whether the data is actually backed up:
For more information on management classes, see Chapter 8, "Understanding Storage Management Policies".
Using the include option in an include-exclude list, you can assign the default management class to a file. You can also assign a specific management class to a file.
You can perform either a full incremental backup or an incremental by date backup. The default is a full incremental backup.
For Windows NT, 2000, XP, Windows.NET: If you are journaling a file system and the journal is valid, the full incremental backup performs a journal-based backup. See Journal-Based Backup (Windows NT, 2000, XP, Windows.NET) for more information. You can perform a full incremental backup without the journal by using the nojournal option. See Nojournal for more information.
You can also use the selective command to perform a selective backup that backs up only the files, directories or empty directories that you specify. For more information, see Selective.
A full incremental backs up all files or directories that are new or have changed since the last incremental backup. During a full incremental backup, the client queries the server or the journal database (Windows NT, 2000, XP, Windows.NET) to determine the exact condition of your storage. Tivoli Storage Manager uses this information to:
If the journal engine service is installed and running, then by default the incremental command performs a journal-based incremental backup on any journaled file systems. Tivoli Storage Manager does not use the journaling facility inherent in Windows NTFS 5 file systems or any other journaled file system.
The journal engine service records changes to an object or its attributes in a journal database. During a journal-based backup, the client obtains a list of files that are eligible for backup from the journal database. Performing backups on a regular basis maintains the size of the journal.
Journal-based backup can increase backup performance. With journal-based backup, the client does not scan the local file system or obtain information from the server to determine which files to process. Journal-based backup also reduces network traffic between the client and server.
Tivoli Storage Manager filters the list based on the current include-exclude list. Tivoli Storage Manager processes, expires, and updates the resulting files according to policy constraints, such as serialization. The management-class copy frequency attribute is ignored during journal-based backup.
The journal engine service excludes specific system files (pagefile, registry, etc.) from having changes recorded in the journal. Because changes to these files are not journaled, Tivoli Storage Manager does not back up these files. See the journal service configuration file tsmjbbd.ini located in the Tivoli Storage Manager installation directory for specific system files that are excluded.
To support journal-based backup, you must install the journaling engine service. Install this service by using the dsmcutil command or the GUI setup wizard. See Using the Dsmcutil Commandfor more information about using the dsmcutil command to install the journaling engine service. See "Journal-Based Backup (Windows NT, 2000 only)" for more information on how to install the journaling engine service using the GUI setup wizard.
If the file specification on the incremental command is a file space, Tivoli Storage Manager processes any journal entries for that file space. Tivoli Storage Manager processes directories and wildcarded file specifications in the same way. Tivoli Storage Manager uses the domain list if you do not specify a file specification.
Note: Journal-based backup may not fall back to the traditional incremental backup if the policy domain of your node is changed on the server, depending on when the policy set within the domain was last updated and the date of the last incremental. In this case, you must force a full traditional incremental backup to rebind the files to the new domain. Use the nojournal option with the incremental command to specify that you want to perform a traditional full incremental backup, instead of the default journal-based backup.
When a user deletes a file with a long name, the Windows operating system may supply a short, or compressed, name to the journal engine service. After the object is deleted, the compressed name may be reused and the deletion notice may no longer identify a unique object. During a journaled incremental backup, the attempt to expire the file will fail because the compressed name is not known to the server. When this occurs, a record is placed in the journal indicating that the current directory is not exactly represented at the server. Use the incrthreshold option to specify what action is taken when this occurs. See Incrthreshold for more information.
Under the following conditions, the journal database is considered invalid and the client reverts to the traditional full incremental backup:
Journal-based backup differs from the traditional full incremental backup in the following ways:
You can use the nojournal option with the incremental command to perform a traditional full incremental backup instead of the default journal-based backup. See Nojournal for more information.
If you perform an incremental backup of a file space on which a volume is mounted, Tivoli Storage Manager does not traverse the mount junction and back up all mounted data. For example, if you have a mounted volume named c:\mount on file space c:, Tivoli Storage Manager backs up only the junction point, not the data under c:\mount.
To back up all data for a file system, including virtual volumes and virtual mount points, run an incremental backup on each virtual volume. You must also perform an incremental backup on the file system.
The exclude.dir option is not valid for a mounted virtual volume if the volume is backed up as a file space. Exclude.dir is valid for a mount point that is backed up.
If you perform an incremental backup of Microsoft DFS root with dfsbackupmntpnt=yes specified, Tivoli Storage Manager backs up only the junction points, not the subtree under the junctions.
If you want to traverse the DFS tree and back up the files and subdirectories of any junction it encounters, specify the dfsbackupmntpnt=no option. If you want to backup both the DFS tree structure and the date contained in the DFS tree you must run two backups: one with dfsbackupmntpnt=yes and one with dfsbackupmntpnt=no.
This option has no effect if you are backing up individual junctions. The exclude.dir option behavior for DFS junctions is same as for mounted virtual volumes. For more information, see Dfsbackupmntpnt.
An incremental-by-date backup backs up new and changed files with a modification date later than the date of the last incremental backup stored at the server, unless the files are excluded from backup by an exclude statement.
If an incremental-by-date is performed on only part of a file system, the date of the last full incremental is not updated, and the next incremental-by-date will back up these files again. Use the query filespace command to determine the date and time of the last incremental backup of the entire file system.
To perform an incremental-by-date backup, use the incrbydate option with the incremental command.
Unlike a full incremental, an incremental-by-date does not maintain current server storage of all your workstation files because:
For these reasons, if you have limited time during the week to perform backups, but extra time on the weekends, you can perform an incremental-by-date backup on weekdays and a full incremental backup on weekends to maintain current server storage of your workstation files.
If the incremental command is retried because of a communication failure or session loss, the transfer statistics will display the number of bytes Tivoli Storage Manager attempted to transfer during all command attempts. Therefore, the statistics for bytes transferred may not match the file statistics, such as those for file size.
If you plan to perform a backup over a network device with limited bandwidth, such as a modem, you can reduce the network traffic by using the subfilebackup option. If you plan to use this option, ensure that you specify the subfilebackup, subfilecachepath and subfilecachesize options during the initial backup of your file. The options specify whether to perform an adaptive subfile backup along with the path and size of the data to be transferred. For information on these options, see Chapter 9, Setting Processing Options. For information about adaptive subfile backups, see Performing a Backup with Limited Bandwidth.
Please see Autofsrename for information about using the Unicode-enabled client.
Tivoli Storage Manager backs up named streams on a file basis only. Backup of a named stream containing sparse file data is not supported. Tivoli Storage Manager will back up a sparse file as a regular file if the client compression is off. Enable file compression (compression=yes) when backing up sparse files to minimize network transaction time and to maximize server storage space.
Microsoft disk quotas do not affect the amount of data you can back up.
Supported Clients
This command is valid for all Windows clients.
Syntax
>>-Incremental--+----------+--+---------------+---------------->< '- options-' | .-----------. | | V | | '--- filespec-+-'
Parameters
You can use these common options with the incremental command: autofsrename, changingretries, domain, incrthreshold, memoryefficientbackup, subdir, subfilebackup, tapeprompt. For information about these options, see Chapter 9, Setting Processing Options.
If you specify a file system, all new and changed files are backed up. In addition, the last incremental date for the file space is updated on the server. If you specify a file or directory, the last incremental date is not updated. This means the file or directory might be backed up again if a later backup is performed using the incrbydate option.
If you specify a file system, specify the file system without a trailing slash.
Examples
Command: Incremental
Command: i c: d: e:
Command: i \home\ngai\