@ Hostname not being overridden by other A record?

Question

My domain's A records are:

Host:           Points to:
@               66.6.44.4
experiments     188.121.46.1    

The @ points to my Tumblr blog, and the experiments subdomain points to my hosting.

The problem I'm having is, experiments.example.com is somehow redirecting (curl shows that it's a 301) to example.com/experiments/. I've checked http://whatsmydns.net and it too confirms that those hosts point to those IPs.

How is this happening? I've emptied my DNS cache a few times so I don't think it's that. Where is that redirect coming from?

Thanks.

Answer 1

Actually this is not a DNS problem, but a webserver issue.

Your webserver running at http://experiments.example.com redirects to http://example.com/experiments/. So check your Webserver configuration to find any redirect directives.

DNS only resolves names to IP addresses. It does not redirect HTTP requests.

HTTP is a protocol. With http://experiments.example.com you connect to a server experiments.example.com (IP 192.0.2.46) on port 80 where your webserver listens, accepts the request and redirects it to http://example.com/experiments/ and your broswer follows this redirect querying host example.com (IP 203.0.113.42) on port 80 to GET /experiments/ there.