Forum Discussion

MW1's avatar
MW1
Icon for Cirrus rankCirrus
May 16, 2012

GTM - DNS question- subdomain

All,

 

really a DNS question more than a GTM question but hoping I can be given direction.

 

 

I need to create records on my GTM in zonerunner for :

 

 

www.country.domainname.com

 

 

in a zone (domainname.com )I already have an A record for www (i.e. url is www.domainname.com)

 

 

 

Do I need to create a subdomain zone of country.domainname.com with then a A record in it of www, or can I just create an A record in the main domainname.com zone which is www.country, or will I be sent to the depths of hell and this is terribly bad practise?

 

 

Thanks to anyone who can shed any light on this!

 

 

 

3 Replies

  • George_Watkins_'s avatar
    George_Watkins_
    Historic F5 Account
    Hi MW,

     

     

    Don't do it. DNS namespace (www.country.domainname.com) consists of labels delimited by periods. RFC 1912 states that "Allowable characters in a label for a host name are only ASCII letters, digits, and the `-' character." Adding periods to hostname labels will likely cause unexpected results for clients consuming your DNS services.

     

     

    In full disclosure, I do this on my home network and it works for my purposes, but I'm the only who uses the DNS server. Definitely not something I would try in a production environment. If you'd like to automate the workload of adding a bunch zone to Zonerunner, consider writing an iControl script. Here is a thread with an example of using iControl to add zone files: Getting Error while using add_zone_file API for creating Management Zone.

     

     

    -George
  • Thanks for the response - I did test t(doing it the wrong way) on the GTM and it does appear to work as you mentioned, however if you update a record (e.g. change the IP of a A record) it creates a duplicate record in the zone and leaves the old record untouched.

     

     

    I am presuming on the GTM's I would simpy define NS records in the main zone (domainname.com) for the subdomain zone, i.e.country.domainname.com and then create a new zone in zonerunner to add the A records to?
  • Yes the correct way would be to create the new zone for country.domain.com and would think the NS records would be part of the new zone..