sockets without owner.

[pluknet]

On 04/04/07, Stefan Lambrev <stefan.lambrev at sun-fish.com> wrote:
> Hello list,
>
> I'm having very strange problem.
> I have near 200 sockets reported by netstat -An, which are NOT reported
> by sockstat and fstat.
> All of them look like (output from netstat -An) :
>
> ffffff0169282000 tcp4       0      0  192.168.13.12.4965
> 192.168.13.3.8080  FIN_WAIT_2
>
> I'm trying to figure out what keeps them active (tcpdump shows traffic
> from 192.168.13.12 to 192.168.13.3)
> The application that create them is stopped before more then a week but
> request are still "flying" around.
>
> I tried fstat |grep ffffff0169282000, but the output is 0 lines.
> Is there any way to close those sockets, as it appears that they are
> stalled and without owner?
>
> And what is the timeout for FIN_WAIT_2 in freebsd ?
> (the rfc doesn't define timeout but I read somewhere that freebsd's
> network stack have timeout)
>
> FreeBSD 6.2-PRERELEASE SMP amd64.
>
> I have access to both IPs - 192.168.13.12 is http balancer and
> 192.168.13.3 is apache server (both were restarted)
>
Maybe I'm wrong, but it looks like if your server didn't close() its connection
for the socket. In that case the server will not send the FIN segment
and the client will not receive it and than will not send the ACK segment
to the server. AFAIK in the Berkeley implementation it should be 11 min timeout
for the client's connection and never (with possible descriptor
exhaustion) for the server' in this situation.

> --
> Best Wishes,
> Stefan Lambrev
> ICQ# 24134177
>
wbr,
pluknet