Why should I keep old Linux kernel versions installed?

Question

I've just updated my Linux kernel and I wonder if there is any other concern apart from being able to recover if the new version can't boot.

What do you think?

Thank you!

Answer 1

The biggest reason I've found for why you might want an old kernel is because it's a specialty kernel and there's no recent counterpart. I have an "old" -rt kernel because there is no "current" one available mainstream.

Specialty kernels aside, though, as far as I can personally tell or care, old generic ones are obsolete except for recovery purposes. I've never had a compatibility issue between an old program and a new kernel.

Answer 2

No other reasons than to be able to boot should the latest upgrade go wrong. I tend to keep one or two older versions available and kick out the rest.