For finding out if something is listening on a port and if so what the daemon is.

lsof -i :[port number]
Gives also the name of the deamon
Sample Output
$ sudo lsof -i :443
COMMAND  PID     USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
apache2 1018     root    5u  IPv4   4121      0t0  TCP *:https (LISTEN)
apache2 1044 www-data    5u  IPv4   4121      0t0  TCP *:https (LISTEN)

0
By: CodSpirit
2010-08-20 11:14:11

3 Alternatives + Submit Alt

What Others Think

When I use it with port 80, it shows me all the processes that are sending requests using that port (Chrome for example) but not the ones listening. Any idea why?
imgx64 · 559 weeks and 5 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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