I've seen questions about how to not log 404 errors to the error log, this is the opposite.
For some reason my apache installation does not log 404 errors to my error log (or to my access log for that matter). I have set the error log properly and see errors going to it, but when I access non-existent pages I simply get my 404 error - the access (but not the 404 error) shows up in the access.log, but I don't see anything in the error log (which makes it hard, for example, to debug why some pages aren't showing up).
My apache (2.4.7) conf settings regarding logs (in the order they are set) are:
ErrorLog ${APACHE_LOG_DIR}/error.log ErrorLog logs/error_log LogLevel warn # Though I've tried setting this to debug LogFormat "%v:%p %h %l %u %t \"%r\" %>s %O \"%{Referer}i\" \"%{User-Agent}i\"" vhost_combined LogFormat "%h %l %u %t \"%r\" %>s %O \"%{Referer}i\" \"%{User-Agent}i\"" combined LogFormat "%h %l %u %t \"%r\" %>s %O" common LogFormat "%{Referer}i -> %U" referer LogFormat "%{User-agent}i" agent LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"" combined LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\"" common LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\" %I %O" combinedio CustomLog logs/access_log common LogFormat "%{HOST}i %h %l %u %t \"%r\" %s %b \"%{User-Agent}i\"" vcommon CustomLog logs/access_log vcommon
So the only ones that I think are relevant to error log (ignoring overwritten settings) are:
ErrorLog logs/error_log LogLevel warn # Though I've tried setting this to debug