Port to PID
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Jump to navigationJump to searchUse the `lsof` command to find which process is listening on a given port.
The -n option for `lsof` turns of reverse name resolution which speeds up the output. Otherwise it will try to reverse each IP address to a name.
For example, say I saw that some process was already using port 69 (normally TFTP). I did not expect this port to be in use, so I ran the following command to find out which process what listening on port 69:
lsof -n -i :69
To find which process is listening on port 80 (you would expect some http server):
lsof -n -i :80
To see who is connected via SSH or SCP look for port 22:
lsof -n -i :22
You can also look for files opened by a given user or command:
lsof -n -u USER
lsof -n -c COMMAND