I read a lot about howto recreate the server certificates (self signed).

But what happens if the certificates are not valid anymore?

-is the server stopping with some services
-is it not possible to install new services.

I like to know what happend if OES or SLES certificates are expired.
I couldn't find something about it on the web, only how to renew.

Maybe someone can explain me, this simple question (i though).