topic resolving a close_wait status on a particular port in Operating System - Linux

resolving a close_wait status on a particular port

Andrew Kaplan — Mon, 27 Feb 2006 12:33:45 GMT

Hi there --

I have a server running Red Hat 7.3 and there is a CLOSE_WAIT status on a particular port that is preventing my starting a program that needs that port available. Is there a way, other than restarting the server, of resolving the CLOSE_WAIT status on the port? Thanks.

Re: resolving a close_wait status on a particular port

Stuart Browne — Mon, 27 Feb 2006 15:03:33 GMT

netstat -nap | grep CLOSE_WAIT

Run this as 'root'. Does this list a PID?

Re: resolving a close_wait status on a particular port

Andrew Kaplan — Mon, 27 Feb 2006 15:13:32 GMT

It appears the pid is 29877. I am referring to the column after the CLOSE_WAIT entry which reads 29877/df.

Re: resolving a close_wait status on a particular port

Andrew Cowan — Tue, 28 Feb 2006 02:10:59 GMT

After killing the process try a "service network" restart as this may refresh the port.

Re: resolving a close_wait status on a particular port

Sergejs Svitnevs — Tue, 28 Feb 2006 03:23:25 GMT

CLOSE_WAIT means that the system is waiting for the local process to close
the socket. The socket doesn't get closed until all the processes that have descriptors for it call close() (or terminate, since that automatically closes all of a process's descriptors).

So you need only to close your program which use a open socket in a listening mode.

Regards,
Sergejs

Re: resolving a close_wait status on a particular port

Andrew Kaplan — Tue, 28 Feb 2006 08:32:29 GMT

I tried to kill the process using the kill -9 syntax as root, but it did not seem to have any effect. Despite that, I ran the service network restart command and while that went by without a problem, the CLOSE_WAIT status of port did not change.

I ran the ps -ef command and grepped for the application, but there was no listing of it.

Re: resolving a close_wait status on a particular port

Andrew Cowan — Tue, 28 Feb 2006 09:56:08 GMT

If the process refuses to die, try killing the parent.

Re: resolving a close_wait status on a particular port

Tucker_1 — Thu, 02 Mar 2006 15:10:33 GMT

Try lsof -i TCP |grep [port# | or named port defined in /etc/services] then kill the associated pid of that process. If this works it could then be incorporated into a script.