The master DNS server field accepts hostnames (though not recommended), IPv4 and IPv6 addresses... However, what of a host that is dual-stacked and has one network go down, yet still be available on the other? What if I update a zone and it pushes, just to have it refuse the notify because the IP is not configured?
This has happened to me a few times, so I'm starting to see why this would be a good idea.
Master: <IPv4 Address> [ ] IPv6? <- checkbox, if enabled, then under it:
Master (IPv6): <IPv6 Address>
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