Hi,

After updating Jenkins with the latest 1.560 and slave.jar (on all slave machines) with latest 2.39, I'm experiencing some random connection problems.

Slaves are either not started at all or they are started but not connected and jobs endlessly wait for available executors.

Here are some screenshots with errors I see after examining the pending job slaves...

The truth is, that the slave machine is long time turned off (turns off 5 minutes after last finished build), so the message about "ignoring connection attempt because the machine is being shut down" is completely senseless.

In some cases, it helps to turn the machine ON manually. After that, the connection is (usually) established. But sometimes not. All worked OK with 1.559 and slave.jar 2.32.