The Simplicity Of A Custom Domain Setup

Custom domain publishing is a very simple way to give your Blogger blog a non BlogSpot URL - when you follow the recommended procedure.

Along with the simplicity, you'll find rather rigid requirements, when any alternative procedure is used.

Too many blog owners, unfamiliar with the complexity of the custom domain infrastructure, try to "fly by the seat of their pants", when they see a requirement that they don't understand.

Improper domain setup, caused by bad decisions, is how many custom domain publishing problems start.

First, understand some of the most common mistakes, made by too many blog owners. Blog owners in the USA may use Google Domains, though others must purchase directly from a registrar.

That reality does not change any of the necessities of proper domain setup, however. Substituting for "Buy a domain", Blogger offers instructions, in How do I use a custom domain name for my blog?.

There are 3 - and only 3 - supported DNS Models.

To understand the significance of the mistakes that are commonly made, first understand the three basic DNS models, involved in custom domain publishing.

1. Published To Domain Root - Symmetrical DNS Configuration. The most obvious configuration uses a symmetrical DNS structure - dual "CNAME" referrals.
   

   mydomain.com. 3600 IN CNAME ghs.google.com.
   www.mydomain.com. 3600 IN CNAME ghs.google.com.

2. Published To Domain Root - Asymmetrical DNS Configuration, aka "Google Apps". If you have a domain with email, FTP, and other possible auxiliary services, you use an asymmetrical structure, which use Google Apps to let you add auxiliary services, with quadruple DNS server redundancy.
   

   mydomain.com.  3600 IN A 216.239.32.21
   mydomain.com.  3600 IN A 216.239.34.21
   mydomain.com.  3600 IN A 216.239.36.21
   mydomain.com.  3600 IN A 216.239.38.21
   www.mydomain.com. 3600 IN CNAME ghs.google.com.

3. Published To Non Root Virtual Host. If you wish to add an additional blog to the domain, maybe to add your Blogger blog to your web site, you setup an additional virtual host.
   

   blog.mydomain.com. 3600 IN CNAME ghs.google.com.

The "Buy a domain" wizard produces an Asymmetrical Configuration. Choice of any one of the three above models determines what URL you may publish the blog.

The published URL, when setup wrong, produces most symptoms.

The published URL is one of the most frequent causes of problems. Do not make any of these mistakes.

• Only publish to a URL defined by "CNAME" referral to "ghs.google.com".
  The referral target, spelled properly, is essential.
  
  
  • Only ghs.google.com
  • Not ghs.l.google.com
  • Not www.ghs.google.com
  • Not ghs.blogger.com
  • Not ghs.blogspot.com
  • Not ghs.gogle.com
  • Not ghs.gooogle.com
  • Not any of a myriad other variations in spelling.
• Do not publish to a URL defined by "A" referral to the "216.239.nn.21" servers.
• The "CNAME" referral must target "ghs.google.com", absolutely.
  • Only ghs.google.com
  • Not ghs.google.com.yourdomain.com
  Understand how to define an absolute referral target.
• The "CNAME" referral must target "ghs.google.com", directly.
  • Only ghs.google.com
  • Not yourdomain.com
  Do not target the domain root, or any other indirect address.
• Understand how to define a referral host.
• Only publish to a referral host using lower case letters.

The domain root, in an asymmetrical DNS model, is similarly crucial.

If you use an asymmetrical DNS addressing, target only the four Google servers, as "A" referrals.

216.239.32.21
216.239.34.21
216.239.36.21
216.239.38.21

Use of these four servers is very specific. Do not make these mistakes.

• Do not provide these servers as "nameservers", as you setup your domain. If your registrar is demanding "nameservers", you need to check your invoice / receipt, and ensure that you did not just pay for "Name Registration", instead of for "DNS Hosting".
  
  You need your own "DNS Hosting", as Google does not provide DNS hosting for private domains. If necessary, use a (free) third party DNS hosting service.
• Do not publish to the URL referred to the four servers. Those servers may only be used to redirect the secondary URL to the published URL.
• Do not include a server provided by your registrar - either substituted for any one of the four, or in addition to the four.
• Do not include any of the three earlier used Google servers.
  

  mydomain.com. 3600 IN A 64.233.179.121
  mydomain.com. 3600 IN A 66.249.81.121
  mydomain.com. 3600 IN A 72.14.207.121

  Those servers are offline - do not include them in your DNS addresses.
• For best results, always include all four servers.
• Understand how to properly define a referral host.
• Though official instructions may disagree, my experience suggests that the domain root must be setup, properly, for a stable custom domain.

The "CNAME" to "ghs.google.com" is sufficient, for the published URL.

If you use "CNAME" referral for any host, only use one "CNAME" referral - do not add a complementary "A" or "CNAME" address, for that host.

www.mydomain.com. 3600 IN CNAME ghs.google.com.

This is all that is needed.

• A second "CNAME" referral is not helpful - and is not supported by many registrars.

  www.mydomain.com. 3600 IN CNAME ghs.google.com.
  www.mydomain.com. 3600 IN CNAME ns1.googleghs.com.

  This is not helpful.
• An additional "A" referral is not helpful - and is not supported by many registrars.

  www.mydomain.com. 3600 IN CNAME ghs.google.com.
  www.mydomain.com. 3600 IN A 64.233.179.121

  This is not helpful.
• You will, however, probably need a second "CNAME" for domain ownership verification. You cannot bypass this requirement - when it is required.

If you must setup the domain yourself, instead of using "Buy a domain", learn the rules - none of them are optional. If you follow the rules, you have a much better chance of having a reliable and working domain - instead of eventually seeing the well known "Another blog ..." or "404 Server Not Found".