Bucky Backup - How Tivoli Storage Manager Manages Backups

This document provides an overview of how Tivoli Storage Manager (TSM) manages backups.

Management Classes

When a file is backed up it is bound to a Management Class. The Management Class dictates how TSM will handle that file and its versions.

Within a Management Class several settings can be specified:

  • Number of versions to keep
    • If client data exists
    • If client data is deleted
  • Length of time to retain extra backup version (number of days to keep inactive versions of files)
  • Length of time to retain only backup version (number of days to keep the last backup version of a file that has been deleted)

A commonly used Management Class is the default Management Class in the 3VER180DAYS Policy Domain.

  • Number of versions to keep
    • If client data exists: 3
    • If client data is deleted: 1
  • Length of time to retain extra backup version: 180
  • Length of time to retain only backup versions: 180

Backup Example

So, imagine a file is created and backed up on day 1. Then the file is edited each day for the next 4 days and backed up each night. No further changes are then made to the file. After 300 days the file is deleted. The following shows what is stored in TSM:

  • Day 1
    • File version 1
  • Day 2
    • File version 1
    • File version 2
  • Day 3
    • File version 1
    • File version 2
    • File version 3
  • Day 4
    • File version 1 is now deleted because it retains a max of 3 version
    • File version 2
    • File version 3
    • File version 4
  • Day 5
    • File version 2 is now deleted because it retains a max of 3 version
    • File version 3
    • File version 4
    • File version 5
  • Day 6
    • File version 3
    • File version 4
    • File version 5
  • ...
  • Day 184
    • File version 3 is now deleted because it is over 180 days old
    • File version 4
    • File version 5
  • Day 185
    • File version 4 is now deleted because it is over 180 days old
    • File version 5
  • Day 186
    • File version 5
  • Day 187
    • File version 5 is retained forever if the file exists on the node
  • ...
  • Day 300
    • File version 5 is now retained for 180 days because the file has been deleted from the node
  • ...
  • Day 480
    • File version 5 is now deleted because it does not exist on the node and is over 180 days old

Keywords:
tivoli storage manager management class schedule versions delete 
Doc ID:
9682
Owned by:
Kevin K. in Bucky Backup
Created:
2009-04-21
Updated:
2020-01-27
Sites:
Bucky Backup, DoIT Help Desk, DoIT Staff, Systems Engineering