Troubleshooting Techniques

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If the new binary still has a master process running, you can send it a TERM signal to

force it to quit:

kill -TERM cat /var/run/nginx.pid

Likewise, any new worker processes that are still running may first be stopped with

a KILL signal.

Note that some operating systems will automatically perform the binary

upgrade procedure for you when the nginx package is upgraded.

Once we have our debug-enabled nginx binary running, we can configure

debug logging:

user www;

events {

worker_connections 1024;

}

error_log logs/debug.log debug;

http {

...

}

We have placed the error_log directive in the main context of the NGINX

configuration, so that it will be valid for each subcontext, if not overwritten
within. We can have multiple error_log directives, each pointing to a different

file and with a different logging level. In addition to debug, error_log can also
take on the following values:

• debug_core


• debug_alloc


• debug_mutex


• debug_event


• debug_http


• debug_imap