Server overloaded? Or is it a bug?

[Daniela]

On Wednesday 04 June 2003 13:15, Robert Watson wrote:
> When X wedges, even if the kernel is still alive, it can be hard to regain
> control of the console.  Here are some things you might try, though:
>
> (1) Try pinging the machine from another machine on the LAN/WAN.  If it
>     responds to pings, then the kernel is at least a bit alive.  You might
>     try logging in and see if the X server process is doing anything
>     particularly unusual.

Yes, ping is working.

>     If you can ping but not build a TCP connection, it could be part of
>     the kernel is starved of resources -- too many sockets open, or the
>     like.

Don't think the sockets are the problem. This machine is also a router for the 
LAN, and the client machines could still surf the net.

>     If you can build a TCP connection but not get an SSH banner back from
>     the server, then maybe you're out of processes and sshd can't fork.

It asked me for the password, and then hanged. I guess it's something with the 
processes, but the kern.maxproc sysctl is set to 4068, and I never have so 
many processes.

>     If you can get partway through the banner but hang later, that might
>     be the result of a file system deadlock of some sort.

This is also possible, but what could have caused it? My file I/O is not 
really heavy.

>     If you can log in, cool, it's probably an X problem and not strictly a
>     FreeBSD problem.
>
> (2) Try setting up a serial console

...

> This will help clarify the problem a bit.  If it's a panic or hang, the
> next steps are generally to rebuild your kernel with debugging symbols and
> DDB, see if you can get stack traces etc (documented in the handbook).
> Having a serial console set up makes this a *lot* easier, since you can
> use the other machine to copy/paste debugging information rather than
> trying to hand-transcribe, get a system core (difficult if system is
> wedged in X), etc.

Can't set up a serial console.

I already have debug symbols everywhere. I have alredy rebooted, and I'm now 
looking for application core dumps (however, I don't think an application 
crashed). Maybe I can reproduce it, I still know everything I did.