How to sub-delegate a reverse zone [KB1240]

How to sub-delegate a reverse zone [KB1240]: "Sub-delegate from less than a class C (< 256 IP addresses)

If you have an IP address range of less than 256 IP addresses, then the best way to sub-delegate reverse DNS for part of that range is to ask your IP address provider to create/change this delegation on their DNS servers.
Technically you could create another level of CNAME redirection similar to "classless IN-ADDR.ARPA delegation" (see above) but this is not recommend because the redirection becomes too deep."

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