AW: Webserver crashes sometimes - don't know why

[Maxim Dounin]

Hello!

On Mon, Jan 07, 2013 at 12:45:52PM +0100, Patrik Kernstock wrote:

> I just found something interest in "dmesg" log:
> [5294633.862284] __ratelimit: 20 callbacks suppressed
> [5294633.862288] nginx[20568]: segfault at aa ip 00007fdc5a44eb41 sp
> 00007fff0260a1a8 error 6 in libc-2.11.3.so[7fdc5a3cf000+159000]
> [5294634.659735] nginx[20569]: segfault at aa ip 00007fdc5a44eb41 sp
> 00007fff0260a0a8 error 6 in libc-2.11.3.so[7fdc5a3cf000+159000]
> [5294634.818078] nginx[20571]: segfault at aa ip 00007fdc5a44eb41 sp
> 00007fff0260a0a8 error 6 in libc-2.11.3.so[7fdc5a3cf000+159000]
> [5294634.819429] nginx[20581]: segfault at aa ip 00007fdc5a44eb41 sp
> 00007fff0260a0a8 error 6 in libc-2.11.3.so[7fdc5a3cf000+159000]
> [5294634.920149] nginx[20567]: segfault at aa ip 00007fdc5a44eb41 sp
> 00007fff0260a0a8 error 6 in libc-2.11.3.so[7fdc5a3cf000+159000]
> [5294635.313816] nginx[20589]: segfault at aa ip 00007fdc5a44eb41 sp
> 00007fff0260a0a8 error 6 in libc-2.11.3.so[7fdc5a3cf000+159000]
> [5294635.402682] nginx[20590]: segfault at aa ip 00007fdc5a44eb41 sp
> 00007fff0260a0a8 error 6 in libc-2.11.3.so[7fdc5a3cf000+159000]
> [5294682.926163] nginx[20596]: segfault at 4a ip 00000000004459df sp
> 00007fff0260a0f0 error 4 in nginx[400000+a3000]
> [5294685.155117] nginx[20595]: segfault at 4a ip 00000000004459df sp
> 00007fff0260a280 error 4 in nginx[400000+a3000]
> [5294686.158466] nginx[21276]: segfault at 4a ip 00000000004459df sp
> 00007fff0260a130 error 4 in nginx[400000+a3000]
> [5294688.683947] nginx[21313]: segfault at 1 ip 00007fdc5a44eb41 sp
> 00007fff0260a0c8 error 6 in libc-2.11.3.so[7fdc5a3cf000+159000]
> [5294695.987059] nginx[21361]: segfault at 1193d ip 00007fdc5a44eb41 sp
> 00007fff0260a0c8 error 6 in libc-2.11.3.so[7fdc5a3cf000+159000]
> 
> Seems to be a error in libc...

It's highly unlikely to be an error in libc, segfaults in libc 
usually heppen when libc functions are called with incorrect 
arguments.

You need to obtain coredump and provide a backtrace, see 
http://wiki.nginx.org/Debugging for details, in paricular these two 
sections:

http://wiki.nginx.org/Debugging#Core_dump
http://wiki.nginx.org/Debugging#Asking_for_help

Please note: it would be good idea to make sure you are able to 
reproduce the problem without any 3rd party modules compiled in.

-- 
Maxim Dounin
http://nginx.com/support.html