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I have a site, www.example.com hosted with a company. I have created a subdomain, sub.example.com and would like it to point to a different server. I have the required ports forwarded for server access, although I am unsure how to set up what I want. I believe it is something to do with the subdomains DNS needs to point to my other IP addressbut I do not have a static IP, merely a DynDNS domain.

The questions are:

  • If I point my subdomains DNS to my ISP's DNS will my non-static IP stay the same as long as I am connected to the internet?

  • Is it possible to use the sub.example.com to directly access the server, rather than forward to the DynDNS-assigned domain?

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2 Answers 2

up vote 3 down vote accepted

Where do you host the name servers for example.com? I assume with the the company that hosts www.example.com. Here is what you do:

  1. Set up your dyndns client so that it updates myhomeserver.dyndns.org with your dynamic IP where myhomeserver.dyndns.org is the domain name you selected from dyndns.

  2. Configure your DNS through your hosting company's DNS control panel so that home.example.com is CNAMEd to myhomeserver.dyndns.org. I.E. create a new CNAME RR for home.example.com that is myhomeserver.dyndns.org..

  3. Profit.

No extra DNS mojo needs to be done. No additional name servers are needed.

NB. The DNS "forwarding" (actually name canonicalization) will be completely invisible to higher level protocols. E.g., when you type "home.example.com" in a browser it will stay that and not change into myhomeserver.dyndns.org. It sounds like that may be the concern driving the second question.

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seems to work, thanks. –  tombull89 Sep 30 '10 at 15:03
This worked for me too. Thanks. –  mouche Apr 21 '11 at 20:05
  • Most likely
  • No, at least not unless there's a service similar to DynDNS that does this.
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