This is not something I've ever had to do before, and in light of the heartbleed bug I've been looking for a guide of how to do it properly, but all I can find are guides on how to log into a server with a certificate instead of a password (but might just be googling the wrong thing?).
I'd just like to know the steps revoke/renew all the keys/certificates associated with ssh access to a server in Debian (Wheezy) Linux, I don't know where they're stored or how they're configured.