Robert Storey wrote:
Dear All,
An interesting and disturbing problem recently appeared on our server
which is running FBSD 5.3. Rather suddenly, all users found themselves
locked out because ssh stopped working. We had to send an email to tech
support at our hosting service (Netsonic). They said this seems to be
happening frequently on many FreeBSD servers (something to do with
reaching the limit of ssh connections). They didn't tell us how to solve
the problem, but they suggested rebooting, which should return the
server under our control. We asked them to reboot and they did, problem
solved for now.
I'm wondering if anyone knows what is causing this, and if there is a
permanent solution? The server was running fine for four months without
issues - this just suddenly came out of the blue.
TIA,
Robert
We had exactly the same problem with 5.3 on a dual opteron machine.
One minute it worked and the next minute it stopped and had to be
rebooted. The host insisted that this was clear evidence that machine
had been compromised but this was nonsense. I have spoken to other
people using 5.2 and 5.3 who report identical behavior. I don't know if
it's a physical connection limit that's causing the problem though,
because only two people log into my BSD server.
I think a safer bet is this worm that tries to compromise servers by
ssh. Perhaps the ssh server isn't cleaning up the failed connections
well enough, or maybe it's detecting an attack and simply shutting down.
This worm can generate a thousand or more connection attempts in a
single session, so I can see how a tiny memory leak could grow into a
big problem in a hurry.
--
John Davis
___
freebsd-questions@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-questions
To unsubscribe, send any mail to "[EMAIL PROTECTED]"
