Messages in this thread | | | Date | Thu, 3 Dec 1998 13:44:04 +0100 (MET) | From | Wojtek Pilorz <> | Subject | Re: IPv4: ssh failure, local port 1023 |
| |
On Tue, 1 Dec 1998, Geert Uytterhoeven wrote:
> Date: Tue, 1 Dec 1998 19:20:03 +0100 (CET) > From: Geert Uytterhoeven <Geert.Uytterhoeven@cs.kuleuven.ac.be> > To: Linux kernel <linux-kernel@vger.rutgers.edu> > Subject: IPv4: ssh failure, local port 1023 > > > Sometimes I have problems using ssh to log in. The ssh connection just doesn't > seem to succeed. Using the `-v' option, the last line it prints is > > Allocated local port 1023 > > If I CTRL-C and retry, it fails again (reproducible). However, if I retry > without breaking the first attempt, ssh gets allocated a different local port > number and the connection succeeds. > > The sshd runs on a Pentium with 2.0.35, ssh client runs on a 68040 with > 2.1.130. > I have also had this problem quite a few times. I cannot explain exactly how this happens, but the patterns seems to be as follows: netstat -a on a destination host (where sshd is run) shows that there is a connection from client machine with port number, say 1023, which is not quite finished (on FreeBSD mchine netstat reports it as having state of TIME_WAIT) On the client machine netstat -a shows a connection from the same 1023 port in state SYN_SENT; Unfortunately I cannot find an easy way to produce this on purpose.
> But I've been seeing this on different types of machines, running both > Linux/m68k and Linux/ia32, with both 2.0.x and 2.1.x kernels, since more than a > year. There seems to be one common thing in the failures: the allocation of > the local port 1023. It doesn't always fail if the local port is 1023, but if > it fails, it's always 1023. > This would depend on number of ssh sessions you are running on your machine? Strange ...
> Needless to say, this is hard to track. Just when I wanted to start using > tcpdump, I couldn't reproduce the problem anymore :-( > What about disconnecting network cable (or modifying routing tables) while some output is going from remote machine and then killing ssh session on client and starting another one?
> Could this be related to a (possible) bug in the m68k IPv4 checksum code? > But then, the first time I saw the problem, it was between two ia32 boxes > running 2.0.x, more than one year ago. > > Anyone with a clue? Thanks! > > Greetings, > > Geert > > -- > Geert Uytterhoeven Geert.Uytterhoeven@cs.kuleuven.ac.be > Wavelets, Linux/{m68k~Amiga,PPC~CHRP} http://www.cs.kuleuven.ac.be/~geert/ > Department of Computer Science -- Katholieke Universiteit Leuven -- Belgium > It was perhaps not much help,
just wanted to share my experiences.
Best regards,
Wojtek Wojtek.Pilorz@bdk.pl
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
| |