In my oppinion there are two excercises to do as an admin, when the server crashes:
1. Report crash to someone, who can fix it.
-after that-
2. Show ppl on server, how they can enjoy the 'crashed mod'. Once when we had this situation and I didnt find anyone on msn, I tried to explain everyone how to play along. Then almost every player stayed online, and didn't quit xD. They were enjoying the game, and weren't disappointed in our services xD. The worst behavior in a situation like this: every admin quit and says: sorry we have a problem, please everyone leave server now :S. We have to stay and make from the problem a bit fun for them xD.