How much a programmer should know about system admin?
system-administration
Solution
It is critical for a programmer to have a Big Picture view of all aspects of software development, deployment, runtime environment, safety, and security.
Otherwise, "innocent mistakes" can be made that have very costly results, and the net effect is one of diminished productivity (or worse).
Know enough about how things work to satisfy the Big Picture for your environment, but you do not need to know how to make them work.
Problem
How much should a programmer should know about system admin? I mean, obviously the more the better. But for the sake of argument, what is the average a programmer should know? I have seen my friend ( a programmer) does database schema design, database backup, database tuning, data migration etc. Sometimes I wonder whether he is a programmer or a system admin.