as I understood in nginx I could specify an error log as warn , error , info , debug , ...
my problem is that I wanna have warn logs and error logs on separate files but as you know if I a specify a file for warn logs then It would include error logs too
so I will have a file containing only error log and another file containing both error log and warn log
but I wanna have a file just for errors and another just for warns
how can I separate them entirely?
In theory, you can achieve what you want by having error_log logging to syslog.
Then create a "rule" in rsyslog configuration to forward different severities to different files.