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Last night I launched a command via nohup on a cluster and then closed the connection. Today I would like to kill this job (I know it's still running because output is being generated in an output file) but I can't even determine its PID. If I type ps -ax, for instance, the name of my executable does not show up. Just typing ps only shows me executables that I have launched this login session.

Any suggestions?

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I use $ps -ef all the time. For me it shows all process (even not owned by me) on linux hosts. Does it help for you ? Get the pid and kill it. – Naai Sekar May 28 '13 at 14:43
It depends on the OS. For BSD-derived systems, ps -aux is reasonably equal to ps -ef on Linux. – Jenny D May 22 '14 at 9:46

Try jobs command, if you can see it there take note of the job number and then kill -9 %job_number_you_recorded

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You can use lsof to find the pid of what has that output file open.

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lsof:command not found. Cluster is running Red Hat: Scientific Linux SL release 5.5 (Boron) – alexvas Feb 16 '13 at 21:40
Run it as root. – Dennis Kaarsemaker Feb 16 '13 at 21:42
I don't have root access on the cluster... Also, why would a command be recognized by root but not by another user? – alexvas Feb 16 '13 at 22:02
Becaue on RHEL 5 and clones, /sbin and /usr/sbin are not in normal users' $PATH. You can use the full path, but lsof works best as root. – Dennis Kaarsemaker Feb 16 '13 at 22:07

do you remeber the name of the process? Try to list with:

ps aux | grep -i $your_process_name

If you find that process you can easily kill it with ($pid = second column):

kill -9 $pid

You will not find that process in your current session, the nohup executed the given program then detached the program from your terminal. This parent-less process's parent will now be the init process (PID #1). You can see this with the command:

pstree -a

If you are sure, only one instance of given process is running you can easily kill with this:

killall -9 $process_name

for example:

killall -9 nano
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pgrep is probably a better tool here than killall, since it can selectively search for the process name (with -f) and only select processes started by the user (-u) – jsbillings Sep 1 '13 at 13:08

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