I've got a DNS (BIND9) and DHCP (ISC-DHCP-SERVER) setup in which the DHCP server dynamically updates the DNS when hosts grab an IP address. I'm currently resubnetting a portion of my network that's not currently handled by DHCP and it's critical that clients can access the servers in this subnet. To avoid interruption to clients, I wish to create static entries pointing to various servers so clients can access them via their FQDN rather than IPs and once I change the subnet these servers are on (and the servers start grabbing DHCP addresses) the clients won't have to modify anything as the FQDN's will then point to the new addresses.
Since DNS is dynamically updated for the zone I cannot manually create records in the zone file since they'll just be overwritten. What I'm wondering is how could one create (permanent until removed) static entries in a dynamically updated zone? Right before the subnet changes, these entries would be deleted and then dynamically re-added by DHCP with the proper addresses.