Short story: I get a 500 error when opening a page, but when I look at the error log, there is nothing about this error. I think every 500 error on front-end should be recorded somewhere, am I right? If yes, where could the error log be?
Long version: I am upgrading my Joomla website from 3.6.2 to 3.6.5. It is a security upgrade, and previously this site has been hacked due to not upgrading in time. From my website's backend, when I click "install upgrade", I get a 500 page. I hosted my website on Linode (Ubuntu 14.04), and use webmin/virtualmin to manage the server. For other sites that are hosted on the same machine with same setting, if I get a 500 error, I can just look at the apache error log from webmin's interface, and I've thought this is where all the apache/php errors are being recorded. But this time, there is nothing in the error log. So I wonder whether there is any 500 error that can't be recorded in log? Or maybe this error was recorded else where? How do I find the log?