Sub-Domain Delegation GTM/DNS


Lets say that you have hosted with a 3rd party DNS provider and you would like to create GTM (BigIP-DNS) DNS load balancing by utilizing Sub-Domain Delegation.

In this scenario, there are 2 GTM. One in each DC (DC-1 & DC-2). The basic set up has been completed and the GTMs are in a common sync-group.

Create A-Records for the 2 GTM using their Listener IP addresses: IN A IN A

gtm1 and gtm2 exist in DC-1 and DC-2 respectively and & are the listener IP address configured on gtm1 and gtm2.

Delegate the sub-domain to the GTM using NS Records: IN NS IN NS

Use CNAME records: IN CNAME

The above DNS records (A, NS & CNAME) will be added to the 3rd party DNS records that is hosting Any request for

will be sent to the 3rd party DNS provider which will then resolve to

because of the CNAME and that will be handled by the GTMs because of the NS & A records.

SOL277 – Sub-domain delegation.