OpenSSH Problem with disconnects

[Alexander Schlichting]

Hi,

 

I am having a big problem with the OpenSSH Daemon on my server. Whenever I
am connected to the server and the connection is idle for a few seconds it
gets disconnected. It's almost impossible to work from remote on the server
when the connection is always getting dropped. The server is running FreeBSD
angmar.domain.com 6.2-RELEASE FreeBSD 6.2-RELEASE #0: Fri Jan 12 11:05:30
UTC 2007     root at dessler.cse.buffalo.edu:/usr/obj/usr/src/sys/SMP  i386 and
the SSHD installed by sysinstall OpenSSH_4.5p1 FreeBSD-20061110, OpenSSL
0.9.7e-p1 25 Oct 2004 . I tried a complete FreeBSD reinstall but it did not
help, I tried various settings like KeepAlive TCPKeepAlive but they did not
help either. I upgraded OpenSSL to 0.9.8e and I installed OpenSSH 4.6p1 but
it did not solve the problem. When I run SSH with loglevel debug I see this
in the auth.log when I am getting disconnected: Read error from remote host
192.168.2.100: Connection reset by peer . When I use strace to monitor the
process I see this on disconnect

 

643   wait4(-1, [WIFEXITED(s) && WEXITSTATUS(s) == 0], WNOHANG, NULL) = 4975

643   wait4(-1, 0xbfbfdc9c, WNOHANG, NULL) = -1 ECHILD (No child processes)

643   syscall_416(0x14, 0, 0xbfbfdc20)  = 0

643   syscall_417(0xbfbfdcd0)           = -1 (errno 4)

643   select(7, [3 4], NULL, NULL, NULL <unfinished ...>

 

I tried to find information's about syscall_417 but had no luck with that. I
am stuck here and have no idea what to do. When I am connected to the server
by FTP I don't get disconnected when the connection is idle ( no nohup or so
being sent ) and when I connect by Telnet I also don't get disconnected when
the connection is idle. I am not sure if I should add the dmesg output here
for sys specs or not. I don't do it now but can give it if needed.

 

I installed Debian on another HDD of the server today and I am not having
any problems there. No SSH disconnects all the time. Thanks for any help.

 

-Alex