Match IP with process

[Fritz-Gerald: Zephir]

I have a process which listens to a port and spawn processes whenever someone connects on that port. e.g.
ps -ef | grep user
user 1234 1 master
user 2345 1234 child_1
user 3456 1234 child_2

I use
netstat -an | grep $PORT
to see which IP is connected to $PORT e.g.
IP_1 port
IP_2 port


I'd like to link the two, match an IP to a process, how could this be done?

[Fritz-Gerald: Zephir]

P.S. Unfortunately, I'll browse for answers in 24hrs from now.

[Jordan Bean · Accepted solution]

And everyone says: "Use lsof."

Get it here:
http://hpux.cs.utah.edu/hppd/hpux/Sysadmin/lsof-4.61/

With it you can find everything in use by a process or port.

$ lsof -np
$ lsof -ni [proto][@host|addr][:port_list]

For example, let's see all the processes on port 23:

# lsof -ni tcp:23

[sven verhaegen]

I agree , LSOF is the tool to use , it tells you the info you need to know follow the previous advise