Device or resource busy
Every now and then, I've encountered this on some Jenkins job and today I wanted to get to the bottom of it:
java.nio.file.FileSystemException:
/var/lib/jenkins/workspace/release-phase-2/src/common/.nfs000000000218264e00002879:
Device or resource busy`
As often is the case, a few Unix commands saved the day. First check what process is keeping this file open:
$ lsof /var/lib/jenkins/workspace/release-phase-2/src/common/.nfs000000000218264e00002879
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
less 22763 escenic 4r REG 0,22 2531 35137102
/var/lib/jenkins/workspace/release-phase-2/src/common/.nfs000000000218264e00002879
Then, figure out the actual file (the NFS file name was misleading here) used. For this, I use the PID in the above listing:
$ ps up 22763
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
escenic 22763 0.0 0.0 10776 956 pts/0 S+ 13:12 0:00 less common/pom.xml
If this is a server, which it normally is, you can have a look at the
output from w to find out from which host the user is connecting to
give a hint of who he/she is (if you're using common users for the
build server):
$ w | grep less
The remedy was just to close the less session and re-run the Jenkins
job. Easy when you know what's wrong. Really weird error otherwise 😊
