I need to change Unix-UIDs of several users while PBS-Jobs might still be running (that were submitted by them). I can stop the queues of course, but I’m wondering if anything could go wrong if a job that was submitted before finishes?
I checked in the postgres database and it seems like PBS is only using usernames, not UIDs directly so I should be fine theoretically.
The job processes will continue to run as the UID set when the jobs started. If the UIDs are changed while the job is running, the jobs may run into permission issues when they try to open new files. There may also be problems copying output back via ssh.
I’d suggest you move all jobs owned by users whose UIDs will change to a stopped queue (or put a hold on them) and let any running jobs for those users complete. You may then safely change the UIDs. Then move the jobs back to their original queues (or release the holds).