reverse delegating range of ip addresses

[Kevin Darcy]

Doug Barton wrote:

> Kimo R. wrote:
> > Hello,
> >
> > I have a class C 192.168.1.0/24. I would like to delegate a range
> > 39-50. In 1.168.192.in-addr.arpa, I add
> > $GENERATE 39-50 $ NS ns1.otherserver.com.
> > $GENERATE 39-50 $ NS ns2.otherserver.com.
>
> This isn't exactly how this kind of thing is usually done. In order for
> this to work the servers you're delegating to would have to have zones
> for each one of those individual IP addresses. It would be easier to do
> an RFC 2317 delegation. In the 1.168.192.in-addr.arpa zone you would do
> this:
>
> $ORIGIN 1.168.192.in-addr.arpa.
> 39-50   NS      ns1.otherserver.com.
> 39-50   NS      ns2.otherserver.com.
> $GENERATE 39-50 $ CNAME $.39-50
>
> Then the name servers you're delegating to just need one zone,
> 39-50.1.168.192.in-addr.arpa.

Well, for only 12 reverse names, it could go either way. I personally
think that delegating each reverse name is a more logical,
easy-to-understand way of doing "classless delegation" than RFC 2317-style
aliasing, but of course the price to be paid is more delegations in the
parent zone, and more zones to be defined/maintained on the delegated
nameservers. At a certain point, these disadvantages outweigh the
advantages, but different folks will put that "more-pain-than-gain" line
in different places.


- Kevin