This really depends. If you have responsibility for a production system that is supposed to be running 24/7, of course Ops will and should call you if there's a problem.
But if you have no such responsibility, you can route to voice mail.
"This really depends. If you have responsibility for a production system that is supposed to be running 24/7, of course Ops will and should call you if there's a problem.
But if you have no such responsibility, you can route to voice mail."
That is an excellent point.
I remember long ago when I was the most junior process engineer at a film plant I once got a late night call.
Production guy: How much does a cubic foot of water weigh?
Me: (Half asleep) About 1000 kilograms per cubic meter
Him: How much per cubic foot?
Me: 64 pounds
Him: Uh Oh.... click
I never did figure out who he was or what he had done... they apparently covered it up nicely.
Of course, you need people on site who can properly define the word 'problem'. I've gotten some very late night calls for severely stupid, non-critical issues.