502-Error but nothing in error.log (anymore)

[bernado]

Hi there,

I'm using nginx on my arm5 to run a seafile-server and ran into a couple of
problems just now. when I open a page that embeds a picture from a certain
folder the picture won't show. When I copy the pictures url and open that
url manually, I get the error:
"An error occurred.

Sorry, the page you are looking for is currently unavailable.
Please try again later
..."
As I've understood, thats a fallback-template for all server-related errors.
But when I open the error.log, it shows me nothing. Only a notice, that some
pid has been created or similar.
I haven't set a specifc path to a log-file in the nginx.conf, so it should
log to the default location, which in my case is /var/log/nginx/error.log,
and it used to do that  back when I had some 403 permission errors with
wrong ownership of files. so it's not the configurations fault. It seems
that it's just that particular kind of error that doesn't get properly
logged.

The access.log in that same folder gets filled with access logs, upon
opening the image it responds with 502.

Any help on how I could debug this further?

thank you

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,242295,242295#msg-242295