One of the least-known secrets about rpm is that it can rollback (undo) package changes. It can take a fair bit of storage space to track the information necessary for rollback, but since storage is cheap, it’s worthwhile enabling this feature on most systems.

Here are cut-to-the-chase directions on using this feature:

1. To configure yum to save rollback information, add the line tsflags=repackage to /etc/yum.conf.

2. To configure command-line rpm to do the same thing, add the line %_repackage_all_erasures 1 to /etc/rpm/macros.

3. Install, erase, and update packages to your heart’s content, using pup, pirut, yumex, yum, rpm, and the yum automatic update service.

If/when you want to rollback to a previous state, perform an rpm update with the –rollback option followed by a date/time specification. Some examples: rpm -Uhv –rollback ‘9:00 am’, rpm -Uhv –rollback ‘4 hours ago’, rpm -Uhv –rollback ‘december 25′.