| I've now found an internet draft at
ftp://ietf.org/internet-drafts/draft-ietf-cidrd-classless-inaddr-02.txt
The following is an excerpt:
The proposed method is fully compatible with the original DNS lookup
mechanisms .. , 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 either.
So maybe someone has already experience with it? Please tell me!
Sebastian
[Posted by WWW Notes gateway]
|
| I know a bit more:
1) The (fairly near) future is that the latest version of named can do what's
called classless delegation (I think that's the right term). Essentially this
is the idea of delegating the reverse lookup of the range x.y.z.a to x.y.z.b to
another server, and setting that other server only to be authoritative for that
range of addresses.
As Mark says, that requires a later version of named than is in DU at present.
I'm afraid I don't know which version that is, but it shouldn't be difficult to
track it down.
If you want to use it now, then get hold of that version of named, and build it
for the version of DU you're using, and off you go. (Of course, by using a
different version of named, then you (your customer) will not get any support
from Digital if they have problems with named ...)
2) One ISP in the UK has a solution that can be implemented immediately on any
version of named. (I think I wrote this up before, but in case I didn't, here
it is ...) In the domain z.y.x.in-addr.arpa, there is a CNAME defined for every
address in the range, of the form a.z.y.x.in-addr.arpa CNAME
a.ab.z.y.x.in-addr.arpa. That is to say, every reverse lookup entry is aliases
to another similar entry, but with an extra level of "sub-domain". Then the ISP
delegates SOA for the ab.z.y.x.in-addr.arpa domain to you, and you define the
real PTR records for a.ab.z.y.x.in-addr.arpa instead of a.z.y.x.in-addr.arpa.
It's interesting that another UK ISP said that "it can't be done", while this
ISP does it regularly! This is a very good indication of the level of technical
support that the two ISPs can provide!
So, you could try to persuade the ISP to do this for your customer...
T
|
| Hi,
I've done it today according to the Internet Draft mentioned in reply .2,
which tells basically the same as alternative 2) in reply .3
There was no need to persuade the ISP to do that: he suggested it himself.
Should anyone like to have a look at a real example, see the network
193.175.194.64, netmask 255.255.255.192. (This is not my current firewall
installation, but it is setup in the same way.) For example type
# nslookup -q=ptr 66.194.175.193.in-addr.arpa.
Thanks for your help,
Sebastian
P.S.
Has anybody built a named supporting classless delegation directly,
i.e. without the additional CNAMES and arpa level? From what sources and
under which DUNIX Version?
[Posted by WWW Notes gateway]
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