Recently when we were testing extranet on two new servers in DMZ, it was not possible to open the URL home page http://extranet3.justanexample.com. Checking the access_log we found that whenever we tried to access the URL, Apache access_log would show HTTP-501 message:
The 501 status code message is displayed when the server does not recognize the document request method. The server is not capable of fulfilling this request and states the request was “Not Implemented”.
Once the load balancer team corrected the SSL certificate, we stopped receiving this error.