OK, what I want is, if a person types the URL "test.MyClientsDomain.net" they actually go to "MyCompanyDomain.com" (but the URL bar shows "test.MyClientsDomain.net").

Here is what I have done so far:

• We purchased a SSL from goDaddy that allows us to add multiple domains and both domains are on it.
• MyCompanyDomain.com is our main site, on a windows server at Rackspace that I have control over, and that works as expected
• I have MyClientsDomain.net registered at NameCheap, the DNS is hosted at a 3rd party (plesk server that I have control of)
• I have added a CNAME at the 3rd party DNS that points test.MyClientsDomain.net to MyCompanyDomain.com
• I have added the "zone" MyClientsDomain.net to the DNS at Rackspace and it points to the webserver's IP
• I have added a CNAME at the Rackspace DNS that points test.MyClientsDomain.net to MyCompanyDomain.com

But it's not working as I want, can you tell me what I am doing wrong?

CodePudding user response：

You aren't mentionning the use of Name Virtual Hosting on MyCompanyDomain.com and for this reason you're ending serving that old domain matching the same IP.

Name Virtual Hosting allows one to publish multiple applications on the same IP, or to publish a very same application with different domain names (what you call "masking"). However for the latter to be completely transparent, nothing like a 301/302 Redirect from one domain to the another should be configure.

Have a look at how configuring