Freeing up a TCP/IP port?

Question

netstat -tulnap shows me what ports are in use. How to free up a port in Linux?

Answer 1

If you really want to kill a process immediately, you send it a KILL signal instead of a TERM signal (the latter a request to stop, the first will take effect immediately without any cleanup). It is easy to do:

kill -KILL 

Be aware however that depending on the program you are stopping, its state may get badly corrupted when doing so. You normally only want to send a KILL signal when normal termination does not work. I'm wondering what the underlying problem is that you try to solve and whether killing is the right solution.