This is some documentation based on Linux things which have driven me crazy. This document is more for my reference than anything else, so don't complain about accuracy, but it's nice to share!

When restarting Apache if you are getting the following errors:

Syntax error on line 127 of /etc/httpd/conf.d/ssl.conf:
SSLCertificateFile: file '/etc/httpd/conf/ssl.crt/server.crt' does not exist

and / or

(13)Permission denied: make_sock: could not bind to address 0.0.0.0:80

check to see if your server knows it's hostname. I had issues after a powercut, and basically my server had forgotten it's hostname locally. Strange that I could ping "LINUX" from my network, but pinging "LINUX" from the actual server didn't work at all. Quick fix - add "LINUX" to the host file pointing to it's physical address.

ie in /etc/hosts

192.168.2.2 LINUX