Cannot find an associated process to a listening port

[Grande Mario]

Hi,
we have the problem that we cannot find an associated process to a listening port.
netstat -a shows the port listening

# netstat | grep 3520
tcp 0 0 *.3520 *.* LISTEN

but we can't find an associated process id when we look with lsof:

# lsof -i -nP | grep 3520 => nothing

Any idea?

THX's
Mario Grande

[Ivan Ferreira]

If you telnet to that port, do you get any information?

Like sshd, if you telnet to that port (22), it reports the sshd version.

[Grande Mario]

Yes, you can telnet to that port.

[Al Licause]

Is this on a cluster or stand alone system ?
If a cluster, did you look at all members ?

Did you try netstat -A; lsof | grep {PCB} ?

[Reto Kisseleff · Accepted solution]

thanks all for responding.
please checkout the attachement, there you'll find the solution.

cheers
Reto