[Gllug] TCP connections not closing

[Formi]

On Sun, 9 Nov 2003, Nix wrote:

> On Sat, 8 Nov 2003, formi moaned:
> >  sysctl -a | grep -i ttl shows:
> >
> >  net.ipv4.inet_peer_maxttl = 600
> >  net.ipv4.inet_peer_minttl = 120
> >  net.ipv4.ip_default_ttl = 64
> >
> >  Any ideas why this is happening?
>
> Because these TTLs don't relate to NAT?
>
> The timeouts you want are in the tcp_timeouts[] array in
> net/ipv4/netfilter/ip_conntrack_proto_tcp.c; there is no way to adjust
> them without hacking the source.
>
> For reference, as of 2.4.22, they are:
>
> static unsigned long tcp_timeouts[]
> = { 30 MINS, 	/*	TCP_CONNTRACK_NONE,	*/
>     5 DAYS,	/*	TCP_CONNTRACK_ESTABLISHED,	*/
>     2 MINS,	/*	TCP_CONNTRACK_SYN_SENT,	*/
>     60 SECS,	/*	TCP_CONNTRACK_SYN_RECV,	*/
>     2 MINS,	/*	TCP_CONNTRACK_FIN_WAIT,	*/
>     2 MINS,	/*	TCP_CONNTRACK_TIME_WAIT,	*/
>     10 SECS,	/*	TCP_CONNTRACK_CLOSE,	*/
>     60 SECS,	/*	TCP_CONNTRACK_CLOSE_WAIT,	*/
>     30 SECS,	/*	TCP_CONNTRACK_LAST_ACK,	*/
>     2 MINS,	/*	TCP_CONNTRACK_LISTEN,	*/
> };
>
> > Source                Destination           Proto   State        TTL
> > 82.35.34.114,58980    81.86.18.XXX,2200     tcp     ESTABLISHED  119:59:59
> > 127.0.0.1,32772       127.0.0.1,53          udp                    0:00:48
> > 192.168.1.25,1229     143.127.8.50,80       tcp     ESTABLISHED   88:01:18
> > 192.168.1.25,1233     143.127.8.50,80       tcp     ESTABLISHED   88:04:27
> > 192.168.1.25,1236     143.127.8.50,80       tcp     ESTABLISHED   88:07:37
> > 192.168.1.22,1110     143.127.8.50,80       tcp     ESTABLISHED   87:51:01
> > 192.168.1.22,1151     143.127.8.50,80       tcp     ESTABLISHED   87:57:22
> > 192.168.1.22,1112     143.127.8.50,80       tcp     ESTABLISHED   87:54:13
>
> You're misreading this display: that 119:59:59 is 119 *hours*, not 119
> *minutes*. So I'd expect it to be still alive.
>
 Yes I'm aware about that, I've seen it before.
 What I don't get is why those particular connections are still hanging
 off when other ones have timed-out? And probably this is basic tcp stuff,
 but which machine sets the TTL, the web server or the client?

 What's the point of having a connection open for 5 days? And why hasn't
 the gateway machine closed it? It should know nothing has been flowing
 all this time.

> Most of those connections have seen no traffic for a good few days, but
> their initial timeout was consistent with that for a connection in
> ESTABLISHED state.
>

 If you reply could you remove my email address? Thanks.

 Formi.



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