Buildbots down

It would appear that most of the buildbots are offline. They have been that way for at least the last 9h since I’ve been online.

Is this a known issue? Is someone dealing with this or are the individual buildbot owners expected to restart their bots?

This appears to be a lab.llvm.org issue, the sanitizer bots are failing to come up because they can not connect to lab.llvm.org:9990.