Hostname won't resolve correctly if apache ServerName isn't localhost

Question

We have a lamp centos 7 server in a datacenter, behind some sort of a Nginx proxy. We only have control over our centos server, we don't know anything about the proxy/firewall or anything. We have installed SSL.

In httpd.conf, ServerName, the one that is not in <VirtualHost>, line 97

if ServerName localhost then the website loads correctly, HTTP only, you get this SSL error

 RSA certificate configured for example.com:443 does NOT include an ID which matches the server name 

if ServerName example.com then SSL loads correctly but if you try to access it either over HTTP or HTTPS you get access denied, just that, probably this error is from Nginx or something not sure

If we omit ServerName, line 97 we get

httpd: Could not reliably determine the server's fully qualified domain name

The datacenter support says

We tested port 80 & 443 for the server and they are open; it looks like a web configuration issue.

Answer 1

Servername must match with the common name of the ssl certificate. Regarding access denied error you need to provide the correct document path that must have the complete rights to access.