Actually, that's the preferred setup to have all the DNS handled on the DNS only machines with the web server or servers pushing the zones to them. If you are going to do it that way, this would be the best setup:
On each web server ==> WHM > Configure Cluster ==> add ns1, ns2, etc. to that area with "Synchronize Changes" for the role
Nameservers (ns1, ns2, etc.) ==> WHM > Configure Cluster ==> add each web server to that area with "Standalone" for the role