How to tell when RedHat was last updated

Question

I have a RHEL 5 server and I want to know the last date in which it was updated.

Is this technically feasible? If yes, how?

Answer 1

One way to do this is to look at the installation dates of the packages.

Show the latest installed rpm:

rpm -qa --queryformat '%{installtime} (%{installtime:date}) %{name}\n' | sort -n | tail -n 1

Note: This won't tell you if someone ran yum update but there were no packages to install / update, which may or may not matter to you.

(Credit to Sean Reifschneider, this information is from his post)