Clean up older installed kernels on CentOS

Linux generally keeps multiple versions of the kernel installed. This is done to maintain backwards stability and allow the selection of an older (tried and tested) kernel if the latest update fails in any way.

On a small system all these kernel versions can quickly add up and waste valuable space. In such case keeping only the needed versions (the latest and the one currently booted, if different) is an acceptable risk to take.

Recover from a broken rpmdb and missing rpm/Packages in CentOS

One can never have too many backups. There’s always room for one more backup. Backups are what keep computers running (most of the time)… Except when backups are not set up. At all. Not even a single antiqued copy exists of what broke down…

Let’s imagine that worst case scenario. Let’s imagine…

Disable yum fastestmirror plugin on CentOS

The fastestmirror plugin may be useful at some points, but it can be a pain in the ass at others.
For example, I tried updating my CentOS installation today and because of the mirror caching it was downloading the updates at 30K/s. After disabling the plugin the speed from picking a different mirror jumped to 3MB/s.

To disable the plugin…