lsof – local open ports

A short one:


lsof -i -P -n | grep LISTEN

This will output all the ports the system is listing on. You might have to prepend “sudo”.

So then the command will be:

sudo lsof -i -P -n | grep LISTEN

The list is long without the “grep”, it will filter the output and only show the lines which contain “LISTEN”.

Oliver from Hubzilla (part of the Fediverse) pointed out that

netstat -anpl

might be helpful too. The command shows all the listing sockets of the Linux machine it is run on. (I added the “l” parameter to just show listing sockets.