Condition GTM wide-ip response based on source IP of requestor when GTM is not primary DNS
Hi - we have a setup where our GTM infrastructure is not our primary DNS - instead, we have separate DNS infrastructure, and for any GTM-managed wide-IPs we have a delegated sub-zone on our primary DNS servers - and the GTMs only handle wide-IPs that are referred to via CNAMEs in our primary DNS. That is, e.g. company.com is hosted on our primary; gslb.company.com is a delegated zone, with name server IPs that are the GTMs; wip.company.com is a CNAME to wip.gslb.company.com, which is a wide-IP on our GTMs.
In that scenario, a client will request resolution of wip.company.com - and our primary DNS server will contact the GTMs to obtain the IP (i.e., will handle the call recursively), and return the IP to the client. But from the GTM's perspective, I believe it will see our DNS server's source as the "client". The only way (at least that I'm aware of) to affect that is to have the client call non-recursively - but the average client doesn't do that, and we wouldn't WANT it to for anything besides these particular WIPs.
This whole problem goes away, of course, if you use the GTMs as your primary DNS infrastructure. But for other reasons, we don't want to switch all clients to accessing our GTM tier for DNS services.
SO - is there any way, without imposing a requirement on the clients to call non-recursively, to condition the GTM response on that original client IP?
If it's relevant, our GTMs are currently running 11.5.3, though that will change to more recent soon. Oh, and sorry, i know it's supposed to be called BIG-IP DNS now.