I am using the DNS Proxy on a Palo Alto Networks firewall for some user subnets. Besides the default/primary DNS server, it can be configured with proxy rules (also called conditional forwarding) which I am using for reverse DNS lookups, i.e., PTR records, that are answered by a BIND DNS server. While it is easy and well-known to configure the legacy IP (IPv4) reverse records, the IPv6 ones are slightly more difficult. Fortunately, there are some good tools on the Internet to help reversing IPv6 addresses.
