During a recent Jenkins plugin upgrade and master restart, it seems that Jenkins failed to resume at least two Pipeline jobs. The pipeline was in the middle of a sh() step when the master was restarted. Both jobs have output similar to the following in the console:

Resuming build at Thu Apr 13 15:01:50 EDT 2017 after Jenkins restart
Waiting to resume part of <job name...>: ???
Ready to run at Thu Apr 13 15:01:51 EDT 2017

However this text has been displayed for several minutes now with no obvious indication on what the job is waiting for. We can see that the pipeline is still running on the correct executor that it was running on pre-restart however, if we log into the server, there is no durable task or process of the script that the sh() step was running. From logging of the script that we were running, we can tell that the command did finish successfully but can't understand how Jenkins lost track of it. From the logging, the time when the command finished was around the same time when the master was restarting (it is difficult to pinpoint exactly).