I'm not sure if dnsmasq is involved in this process on pfSense or not.

Before pfsense, we'd do this in BIND thusly:

zone "firstpartner.com" { type forward; forwarders { 1.2.3.4; 5.6.7.8; w.x.y.z; };

I'm intentionally over-explaining this in the interests of specificity:

We currently use dnsmasq to direct local queries for our primarydomain.com. Anything that doesn't match a host override entry in pfSense gets passed off to our external name servers, as defined elsewhere in pfSense.

There are certain other zones which are not publicly accessible, let's call them firstpartner.com and secondpartner.com that each have various subdomains that their own name servers handle.

I need a way to define a list of name server IPs for each domain zone (see BIND example above).

Thanks in advance for any help you can provide.