I'm not a SysAdmin but I like to put my hands on my servers.
Most of the times I have a specialist that handles most of the boring stuff but if not I'm not afraid to roll up my sleeves and get the stuff done.
Like said in other comments, I strongly believe that most senior devs are pretty good at administration of their servers, it's too much at stake and we need to be on top of what's going on at all levels.
Note: The definition of senior developer have suffered some strange changes in the last couple of years
I've got a guy on my team who takes care of most of that stuff. I, and others on the team, rely on his skills and perspective. I just hope he knows how much we appreciate it. (And this is a reminder to make sure he does.)