Non-Octet Boundary Delegation (RFC 4183)

Simon Hobson dhcp1 at
Wed Sep 21 20:55:03 UTC 2011

Stas’ wrote:
>I've tried to use "zone" for a reverse
>zone but it didn't work.

No it won't. The reverse zone config option sets 
the *base* to which dhcpd adds the reversed 
address - so in your case it would (I believe) 
try and update

Bear in mind that the technique you quote does 
not in fact rely on any hard-codes support for it 
- it's merely a use of PTR records to add a 
second level of indirection, has a PTR record to, and ns records 
allow the client to then query another server to 
map back to a FQDN.

If you read section 6, it mentions using 
alternate domain names - is only 
really a convention to make all the reverse zones 
easily findable from the root, and since you are 
running a custom bit of reverse zone with 
pointers to it's records, you can put this 
anywhere (such as reverse.mydomain.tld - but 
obviously using real names !).

So if you run your own alternate reverse domain 
tree under, then you can 
get the owner of to create 
pointer records to for the addresses 
you use, and let dhcpd update that zone by 
setting the reverse zone root to

Simon Hobson

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author Gladys Hobson. Novels - poetry - short stories - ideal as
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