How TSM point in time (PIT) restore works


The Tivoli Storage Manager point in time restore function is used to restore a file space, directory, or file to a previous condition. While a point in time restore can be useful for restoring the state of a system to an earlier date, it also has limitations - it can indirectly restrict what files and folders are selectable for the restore (such as from the GUI or web interface).

How to do TSM Point In Time Restore

Take the following example, which assumes that directories are bound to the same management class as files:

C:\ 
|
|-folder1
|
|-file1.txt(static)
|
|-file2.txt(changes before each backup)
|
|-folder2(static)

Copygroup settings for this client (for both directories and files):

Verexists = 7 versions of a file(file exists on the original system)
Verdelete = 7 versions of a file(file no longer on the original system)
Retextra = 7 days
Retonly = 7 days

Actions:
Assume that file2.txt changes every day, and a schedule backs up this filespace every day. When each incremental backup occurs, it sends a new active version of file2.txt, and a NEW ACTIVE version of folder1. In this example, the following table would result. This shows the backups that are available on Day 8, looking back for each of the prior 8 days (including Day 8). Active copies of the backed up file and folder are represented by the letter "A", inactive copies by the letter "I", and versions deleted from the filespace by the letter "X", as shown below.

On Day 8, if a point in time restore of either file1.txt or folder2, using Day 1 as the point in time criteria, it would fail to see any folders under C:\ (as viewed by the GUI or web client). That is, folder1 and any of its contents are not visible for selection under a point in time restore. Why ?

The Tivoli Storage Manager client GUI/web client GUI point in time restore requires an active or inactive version of that folder to exist (at the point in time specified by the user) so that it can display items from within that folder to restore. Since folder1 now has a point in time scope going back only to Day 2, folder1 and its contents are unavailable because a backup version for that folder no longer exists at that point in time. Thus, nothing within that folder (active or not) can be selected for restore from the Tivoli Storage Manager client GUI/web client GUI.

To restore a folder or file to a particular point in time (such as file1.txt or folder2), use the 'display active/inactive files' option instead. With the Tivoli Storage Manager client GUI/web client GUI, select the 'View' menu, then select the 'Display active/inactive files' option. This is the equivalent of using the Tivoli Storage Manager command line client command 
restore c:\* -pick -inactive -subdir=yes
restore "/user/project/*" -pick -inactive

Select the version to be restored, based on the date and time criteria. Refer to the Tivoli Storage Manager B/A client manual for further information regarding the use of the client command line and its available options.

Alternatively, restore the filespace using the Tivoli Storage Manager client command line, which does not have this restriction. Use the PITDATE and PITTIME options to specify the desired point in date/time.
restore -pitd=8/17/2016 -pitt=13:00:00 /home/mydir/

Managing proper versions of directories can be maintained using the DIRMC option in the dsm.opt file. See the Tivoli Storage Manager client manual for details.




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