One of the most valuable and definitly one of the most useful aspects of the history command is the ability to undo or redo a transaction. Below is an example of its use:
# yum history undo 1
...
Undoing transaction 1, from Fri Nov 27 22:39:59 2009
Install 0xFFFF-0.3.9-4.fc12.i686
Resolving Dependencies
--> Running transaction check
---> Package 0xFFFF.i686 0:0.3.9-4.fc12 set to be erased
--> Finished Dependency Resolution
Dependencies Resolved
==============================================================================
Package Arch Version Repository Size
==============================================================================
Removing:
0xFFFF i686 0.3.9-4.fc12 installed 100 k
Transaction Summary
==============================================================================
Remove 1 Package(s)
Reinstalling 0 Package(s)
Downgrade 0 Paquete(s)
Is this ok [y/N]:y
Downloading Packages:
Running rpm_check_debug
Running transaction check
Running transaction
Erasing : 0xFFFF-0.3.9-4.fc12.i686 1/1
Erased:
0xFFFF.i686 0:0.3.9-4.fc12
Complete!
The contents of the history must have changed:
# yum history
...
ID | Login user | Date and time | Action(s) | Altered
-------------------------------------------------------------------------------
2 | root <root> | 2009-11-27 23:07 | Erase | 1
1 | root <root> | 2009-11-27 22:39 | Install | 1
And now the transaction can be done again.
# yum history redo 1
...
Repeating transaction 1, from Fri Nov 27 22:39:59 2009
Install 0xFFFF-0.3.9-4.fc12.i686
...
