topic Re: killing sockets in red hat linux in Operating System - Linux

killing sockets in red hat linux

Oved — Mon, 26 Jul 2004 12:28:58 GMT

Hey,

I would like to know how can I kill/remove a socket in linux.

In HP-UX I can use ndd to do this, but linux doesn't have ndd.

Thanx,
Oved

Re: killing sockets in red hat linux

Fred Ruffet — Mon, 26 Jul 2004 12:44:46 GMT

What do you mean by "kill/remove" a socket ?
Do you want to close an open port ?

For me ndd helps tuning some network parameters. This can be an equivalent to Linux sysctl, which offers to tune kernel parameter, and, in your case, network ones.

Regards,

Fred

Re: killing sockets in red hat linux

Oved — Mon, 26 Jul 2004 12:54:11 GMT

Hey,

I mean to close an open socket...
ndd can do it in HP-UX

(There are applications with a "bug" that causes sockets in "CLOSE_WAIT" state to remain in the system, and it causes problems with that applications. )

Thanx,
Oved

Re: killing sockets in red hat linux

Huc_1 — Mon, 26 Jul 2004 13:58:07 GMT

One way to do this could be

ex: (from root)
#lsof -i | grep "CLOSE_WAIT"
# mozilla-b 5914 himself 3u IPv4 49447 TCP 10.22.55.11:ssh->whatever.dom:32798 (CLOSE_WAIT)

then you could use some form of KILL on pid 5914

Hope this help you out.

Jean-Pierre

Re: killing sockets in red hat linux

Oved — Mon, 26 Jul 2004 14:10:10 GMT

It doesn't help so much, because in the cases I want to solve the socket is hang without a process.

I am looking for a solution just like ndd in HP-UX.

Thanx,
Oved

Re: killing sockets in red hat linux

Steven E. Protter — Mon, 26 Jul 2004 14:29:22 GMT

Since ndd does not exist in Linux, a few wild suggestions:

1) Find the source code for ndd, port it and compile it in Linux
2) try the binaries and see if they work.
3) Write a program in c that does what you want.

SEP

Re: killing sockets in red hat linux

Olivier Drouin — Mon, 26 Jul 2004 14:50:53 GMT

a socket in close_wait without a process?? I'd like to see this.

Re: killing sockets in red hat linux

rick jones — Mon, 26 Jul 2004 21:46:50 GMT

the ndd thing in HP-UX is a kludge that should only be used by the truly desparate until the bug(s) in the application(s) can be fixed. As such, I'm not terribly surprised that there might not be a ready replacement in Linux. If someone becomes "dependent" on the ndd connection closing stuff, they are only adding little to little to eventually have a big pile.

CLOSE_WAIT without a process would indeed be a neat trick, and would imply a bug in the transport/kernel. however, unless I read too fast, I think there wasn't mention of the process going away, just lingering and leaving connections in CLOSE_WAIT (bug 1) and then if I extrapolate, leaving things unable to restart (bug 2 - not setting SO_REUSEADDR - but that one is a WAG)