NGINX 500 http error

[Maxim Dounin]

Hello!

On Fri, Nov 15, 2013 at 05:51:16AM -0500, fatine,al wrote:

> Hi,
> 
> I have a lot of 500 http error in nginx access.log.
> I think it's due to the number of requests that nginx receives. Because when
> I was testing the configuration with one ip adress I don't have this error
> but when I redirect all client traffic (sometimes more than 2000
> simultaneous connexions) to nginx I'm getting 500 http error.
> I don't have any error log in error.log.

The 500 errors usually indicate either configuration problem (e.g, 
an infinite rewrite loop or something like this) or some resource 
shortage (memory, file descriptors, space for temporary files, and 
so on).

> I tried to modify this parameters : worker_connections,
> worker_rlimit_nofile, keepalive_timeout, proxy_connect_timeout ...
> 
> And then I start to get this logs in error.log :
>       worker process XXXXX exited on signal 11

Here nginx exits due to memory access violation.  This is a 
serious problem and usually indicate a bug somewhere (well, it 
might be also hardware problem).

First of all, it might be a good idea to show "nginx -V" output 
(and basically make sure you are using latest version and no 3rd 
party modules), and obtain core dump and show a backtrace.

See here for basic instructions and more details:

http://wiki.nginx.org/Debugging

>       an upstream response is buffered to a temporary file
> /var/lib/nginx/proxy/2/00/0000000002
>       failed (104: Connection reset by peer) while sending response to
> client

These are not problems per se.

> Here is my nginx.log conf :
> 
> user www-data;
> worker_processes 4;
> worker_rlimit_nofile 50000;
> pid /var/run/nginx.pid;

[...]

>         include /etc/nginx/sites-enabled/*;

Note that configuration you've provided isn't nearly a full one.  
It lacks an unsepcified number of included files.

-- 
Maxim Dounin
http://nginx.org/en/donation.html