On 2018-03-28 12:46 -0500, Matthew D. Hardeman wrote: > As an aside, for smaller than /24 delegation, an ISP can literally > further delegate reverse lookup to a zone of a single IP address, > allowing smaller customers direct access to update the reverse DNS for > those IPs within their own name servers, if desired. This configuration > is rare, but exists.
This is documented in RFC 2317 - Classless IN-ADDR.ARPA delegation aka BCP 20 This document describes a way to do IN-ADDR.ARPA delegation on non- octet boundaries for address spaces covering fewer than 256 addresses. The proposed method should thus remove one of the objections to subnet on non-octet boundaries but perhaps more significantly, make it possible to assign IP address space in smaller chunks than 24-bit prefixes, without losing the ability to delegate authority for the corresponding IN-ADDR.ARPA mappings. The proposed method is fully compatible with the original DNS lookup mechanisms specified in [1], i.e. there is no need to modify the lookup algorithm used, and there should be no need to modify any software which does DNS lookups. -- Patrick Mevzek _______________________________________________ Acme mailing list [email protected] https://www.ietf.org/mailman/listinfo/acme
