: HTTP 301 redirect http://.example.com to http://www.example.com One of my customers has recently had their site reviewed against best practice for security, SEO, end-user experience etc, and interestingly

@Welton855

Posted in: #301Redirect #Dns #Domains

One of my customers has recently had their site reviewed against best practice for security, SEO, end-user experience etc, and interestingly one of the points highlighted in the final report was that they stated the customer should:


"Put a permanent (HTTP 301) redirect to www.example.com on
.example.com .


At present there are A records for www and @ with a 301 redirect when the requested host name is missing the www prefix (I've checked this is working correctly), however there are also subdomains such as webmail.example.com and imap.example.com etc.

Without using an asterix (*) A record to catch-all, how can I address this point?

I've always thought the hostname part could never start or end with a full stop but that they were used only as separators, and having checked, IETF RFC 1035 states, p8, s2.3.1, "Preferred Name Syntax":


The labels must follow the rules for ARPANET host names. They must
start with a letter, end with a letter or digit, and have as interior
characters only letters, digits, and hyphen.


And while the section title uses the word Preferred the paragraph at s2.3 prior to the above paragraph makes it clear that this syntax is mandatory for Internet-connected systems.

Does anyone believe this domain beginning with a dot but no subdomain could be considered valid under any circumstances? If I try to connect via HTTP I get the error:


Domain name lookup failed: .example.com/

(Note: real domain name substituted for example.com throughout this question)

Vote Up Vote Down

Login to post a comment!