Hi,
I wrote a small migration helper for ISC DHCP to Dnsmasq on OPNsense.
The main goal is reviewability: inspect the current state, generate a migration profile, show a plan, and only then apply changes after confirmation.
Only the core DHCPv4 migration path has been tested by me. Everything else should be considered untested or experimental.
I am sharing this as-is. I cannot guarantee support, fixes, further development, or additional testing. I also cannot run further tests myself.
Functions are explained in
sh opnsense_dhcp-migration-isc-to-dnsmasq.sh --help
Hope this could be helpful though.
Cheers grisey