Just to add to the excellent comments already posted here, using +trace can be helpful in seeing how things are delegated. I use the paid version of DNSreports to provide a non-tech friendly version of the delegation, which has the added benefit of beings able to trace it down other "branches" as well, when multiple NS servers are listed.
Frank -----Original Message----- From: bind-users-boun...@lists.isc.org [mailto:bind-users-boun...@lists.isc.org] On Behalf Of Michael Milligan Sent: Wednesday, June 03, 2009 8:42 PM To: Scott Haneda Cc: Bind Mailing Subject: Re: PTR delegation Scott Haneda wrote: > On Jun 3, 2009, at 11:53 AM, Scott Haneda wrote: >> >> 1) Is it possible to determine what ip range/space has been given to >> user of that IP space? For example, in a colocation environment, I am >> given say, a /24, and I want to look that up and see if it really is a >> /24. I have found the -x option which is making life a lot easier to >> find PTR records. Only your local router knows for sure. DNS reverse-mapping delegation and routes in the routing tables often have little or no relation to each other. They are used for entirely different purposes, of course. >> >> 2) Given an IP that does not have a PTR, how do I determine if it has >> been "sub delegated" (?) to the user of that IP? I need to learn >> whether or not I need to contact the IP provider, and ask for a PTR >> record, or if I need to add one in myself. Follow the delegations. Or find where a missing delegation should be... > I was thinking and testing, and I believe I can answer part of my own > question, but please correct and advise where I am wrong. > > Given an ip of 64.84.37.2 > $dig -x 64.84.37.2 > 2.37.84.64.in-addr.arpa. 3589 IN PTR capone.hostwizard.com. > > So I clearly have a PTR, but I want to see who has been delegated > control of the PTR. > Dropping the trailing 2 > $dig 37.84.64.in-addr.arpa NS > 37.84.64.in-addr.arpa. 3538 IN NS ns1.nacio.com. > 37.84.64.in-addr.arpa. 3538 IN NS ns3.nacio.com. > 37.84.64.in-addr.arpa. 3538 IN NS ns2.nacio.com. > > This to me looks like nacio.com in this case is going to control the PTR > zones? Zone (not plural), yes. > I can go to arin.net and do a lookup there, and find that I have been > dished out a /26, how do I use dig to get that same answer? You really can't. See above. All you can do is follow the delegation path and see where it ends. In the case of a *routed* subnet smaller than a /24 prefix, then you may or may not be able to get it delegated to you in DNS ala RFC 2317 depending on the competence or desire/will of your co-lo provider to do it. Regards, Mike -- Michael Milligan -> mi...@acmeps.com _______________________________________________ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users _______________________________________________ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
