Installation and User's Guide

You can perform the backup only on formatted volumes; not on raw logicalvolumes. You can either use image backup with file system incremental or you can useimage backup with image incremental mode to perform image backups of volumeswith mounted file systems.The following are some examples of using image backup with file system incremental.v To perform a full incremental backup of the file system: dsmc incremental h:v To perform an image backup of the same file system: dsmc backup image h:v To periodically perform incremental backups: dsmc incremental h:You must follow the next steps in the order shown to ensure that the serverrecords additions and deletions accurately.Use this command to restore the file system to its exact state as of the lastincremental backup: dsmc restore image h: -incremental -deletefiles.During the restore, the client does the following:v Restores the most recent image on the server.v Deletes all of the files restored in the previous step which are inactive on theserver. These are files which existed at the time of the image backup, but weresubsequently deleted and recorded by a later incremental backup.v Restores new and changed files from the incremental backups.If you do not follow the steps exactly, two things can occur:1. After the original image is restored, all files backed up with the incrementalcommand are restored individually.2. If you perform a backup image before performing an incremental, files deletedfrom the original image are not deleted from the final restored file system.The following are some examples of using image backup with image incremental mode.v To perform an image backup of the same file system: dsmc backup image h:v To perform an incremental image backup of the file system: dsmc backup imageh: -mode=incrementalThis sends only those files that were added or changed since the last imagebackup to the server.v To periodically perform full image backups: dsmc backup image h:v To restore the image: dsmc restore image h: -incrementalOn restore, Tivoli Storage Manager ignores the deletefiles option when theimage+image incremental technique of backing up has been used. The restorewill include files that were deleted after the last full image backup plus thelatest versions of files added or changed after the last image backup.Note: You should perform full image backups periodically in the following cases.This will improve restore time because fewer changes are applied fromincrementals.v When a file system changes substantially (more than 40%).v Once each month.v As appropriate for your environment.The following restrictions apply when using the image backup with imageincremental mode:vThe file system can have no previous full incremental backups produced by theincremental command.Chapter 13. Using commands 545