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I setup a DNS configuration for iodine.ninjanet.info, but when I perform a "dig iodine.ninjanet.info", I get a SERVFAIL, which leads me to believe I made a mistake in my configuration. I think I may have specified that the nameserver for iodine.ninjanet.info is iodine.ninjanet.info, so a circular dependency is created whereby a user must resolve iodine.ninjanet.info in order to resolve iodine.ninjanet.info (can someone confirm?).

To my great surprise, if I perform "dig z11.iodine.ninjanet.info", the DNS server responds with a CNAME record (ie. somehow, dig was able to get an answer from my iodine server).

I'm 99.8% sure it is NOT due to a cache somewhere, since I can reproduce using entirely new/unique hostnames for the iodine server that were not in any cache. I was thinking maybe the DNS server was providing some glue records, but as far as I can tell, the additional data sections are all empty.

I'm trying to understand what's going on here / how this works. If dig is unable to resolve iodine.ninjanet.info to an ip address, how is dig able to resolve z11.iodine.ninjanet.info for which iodine.ninjanet.info is a nameserver? What am I missing here?


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That is interesting. Now I am even more confused. If I dig ns.iodine.ninjanet.info, I get, which appears to be reserved as private network space, so I don't understand how this address could be valid. Certainly not an address I setup. All I did is setup an A record (iodine-> and an NS record (iodine->iodine.ninjanet.info). At the address, I have a DNS server that responds to zXX.iodine.ninjanet.info where XX is a number. I don't understand where the ns.iodine.ninjanet.info came from, nor do I understand how zXX appears to be served from there. –  Diana Fong Apr 2 '13 at 5:17
I am starting to think that NameCheap (my registrar) is doing fancy things with the host records. I am thinking that ns.iodine.ninjanet.info is owned by them, and when I add my NS record, they are having their name server consult my name server. Does this make any sense, or am I completely off base? I am also still very confused as to why/how their nameserver has a 10.x.x.x address. –  Diana Fong Apr 2 '13 at 5:46
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