What processes are using which ports on unix?

Question

Hi there,

I need to find out what ports are attached to which processes on a unix machine (HP Itanium). Unfortunately, the lsof is not installed and I have no way of installing it.

Does anyone know an alternative method? A fairly lengthy google hasn't turned up anything.

Thanks.

Answer 1

netstat -l (assuming it comes with that version of UNIX)

Answer 2

Try "pfiles PID" to show all open files for a process.

Answer 3

I know FreeBSD has sockstat.

Answer 4

Given (almost) everything on unix is a file, and lsof lists open files...

Linux : netstat -putan or lsof | grep TCP

OSX : lsof | grep TCP

Other Unixen : lsof way...

Answer 5

netstat -pln

EDIT: linux only, on other UNIXes netstat may not support all these options.

Answer 6

netstat -ln | awk '/^(tcp|udp)/ { split($4, a, /:/); print $1, a[2]}' | sort -u

gives you the active tcp/udp ports. Then you can use the ports with fuser -n tcp or fuser -n udp, as root, and supposing that fuser is GNU fuser or has similar options.

If you need more help, let me know.

Answer 7

Assuming this is HP-UX? What about the Ptools - do you have those installed? If so you can use "pfiles" to find the ports in use by the application:

pfiles prints information about all open file descriptors of a process. If file descriptor corresponds to a file, then pfiles prints the fstat(2) and fcntl(2) information.

If the file descriptor corresponds to a socket, then pfiles prints socket related info, such as the socket type, socket family, and protocol family.

*In the case of AF_INET and AF_INET6 family of sockets, information about the peer host is also printed.*

For example, see http://www.theunixblog.com/2007/01/find-out-which-process-is-using-port.html

Answer 8

Thanks all for your input. My main problem here is that I don't have permissions on the box to install anything. I've managed to solve my specific problem anyway.