GTM as a Forwarder to multiple ADs

Hello,

I think you are on track; nothing is missing. Just ensure that the return traffic from the DNS servers is routed through the F5 GTM again. You can create two listeners for both TCP and UDP requests.

you can also, add a caching layer on the F5 GTM using the DNS profile attached to the listener.

https://techdocs.f5.com/content/kb/en-us/products/big-ip_gtm/manuals/product/gtm-implementations-11-5-0/8.html

Thanks,

Mohamed Salah