Identifying Port Usage

[Chuck Ciesinski]

Is there a best method for identifying what application is running on s specific port? I would like to identify what is running on say port 8080 or 2026, etc.

Thanks in advance,

Chuck

[Dave Olker · Accepted solution]

Hi Chuck,

I've always found lsof to be the best way to map applications to port numbers.

Regards,

Dave

[A. Clay Stephenson]

Netstat -an can be of some help but, by far, the most direct mapping of port usage to a process is lsof. You can get lsof from any of the HP-UX Porting Centre's and is one of those utilities that no UNIX box should be without.

[Jeff Schussele]

Hi Chuck,

You can also go to iana.org to see what ports software *should* be using. It's no guarantee but it can get you started - here:

http://www.iana.org/assignments/port-numbers

HTH,
Jeff

[Ralph Grothe]

I am not sure if things have changed by know
but I felt inclined to add that I didn't find the prebuilt binaries of lsof from the porting centre of much use since they used to be 32bit builds which crashed while executing them on our 64bit OSes.
I had to compile a 64bit binary myself from the sources that could be used on our 11.11 v1 boxes.
But compilation was straight-froward.
lsof is defenitely the best tool for questions like yours.
As an aside I would like to mention that the GNU netstat command as can be found on all Linux distros has many more features than the vanilla netstat of the venerable Unices.
One such feature is the -p switch to also identify the processes that use the sockets.
You could for instance issue

netstat -tnp

Maybe you could try to compile GNU netstat for HP-UX as well?

[Victor Fridyev]

Hi,

Run
#> lsof +M |grep -e 8080 -e 2026
and you will see the process which running on the portd

HTH

[Sandman!]

# lsof -i@hostname:8080 -i@hostname:2026

if you don't specify the hostname it will show all hosts, remote and local, that are running apps on the supplied ports (8080 or 2026).