Re: ssh: connect() stalls on RedHat 5.1 / kernel 2.0.34

Ville Herva (vherva@niksula.hut.fi)
Wed, 17 Jun 1998 06:43:29 +0300

On Wed, Jun 17, 1998 at 12:11:29AM +0100, you [Alan Cox] claimed:
> > I can't imagine how this could be a bug in ssh (the connect()
> > parameters are perfectly correct according to strace), but
> > I never get these stalls with other programs doing connect().
> > Further more, I've not seen this on any other RH 5.1 or kernel
> > 2.0.34.
>
> Its probably happening in a case where the socket in question is
> in TIME_WAIT from a previous connect. 2.0.34 ought to be replying
> to that however. Can you send me a tcpdump. I think I know the fix
> especially if 2.0.33 doesnt show it.
>
> Alan

I can't say 2.0.33 doesn't do that, since I've not tested 2.0.33 on the
same platform. I can say that I've never seen this on the other
2.0.33-machines I've used (much more than 2.0.34), though.

The machine I've tried to connect is 2.0.33, though, but as I said I could
even telnet to the same port from the same machine while ssh was stalling
in connect(). BTW: The local port allocated for the lagging connection
always
seems to be the same (1023).

In netstat it says

tcp 0 2 client:1023 server:22
SYN_SENT

>From tcpdump I get [all the packets related to the local port connect()]
reports having had via strace.

06:42:07.856907 client.1023 > server.22: S
2665709351:2665709351(0) win 512 <mss 1460>
06:42:10.856907 client.1023 > server.22: S
2665709351:2665709351(0) win 32120 <mss 1460>
06:42:16.856907 client.1023 > server.22: S
2665709351:2665709351(0) win 32120 <mss 1460>

Hope I did that too much, ask for more if so.

-- v --

v@iki.fi

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu