[dns-operations] Inconsistent NS records for ARPA zones at OpenDNS

[Frank Bulk]

I tried Ulevitch yesterday at his private email address, but didn't get a
response, so I'm reaching out here.  Both yesterday and today our automated
DNS checks (which check NS records for domains we host, both the forward and
reverse ones) show inconsistent results at resolver1.opendns.com and
resolver2.opendns.com.

Inconsistent in the sense that it doesn't match up with that we've
configured, as well as resolver1 and resolver2 don't match up for some of
the ARPA zones.  Here's some examples; the output from Google is correct.

nagios:/home/fbulk# dig NS 10.31.96.in-addr.arpa @resolver1.opendns.com
+short
NS1.MTCNET.NET.
NS1.NETINS.NET.
nagios:/home/fbulk# dig NS 10.31.96.in-addr.arpa @resolver2.opendns.com
+short
NS1.MTCNET.NET.
NS1.NETINS.NET.
nagios:/home/fbulk# dig NS 10.31.96.in-addr.arpa @8.8.8.8 +short
ns1.netins.net.
ns2.mtcnet.net.
ns1.mtcnet.net.


nagios:/home/fbulk# dig NS 7.31.96.in-addr.arpa @resolver1.opendns.com
+short
ns2.mtcnet.net.
ns1.mtcnet.net.
ns1.netins.net.
nagios:/home/fbulk# dig NS 7.31.96.in-addr.arpa @resolver2.opendns.com
+short
NS1.NETINS.NET.
NS1.MTCNET.NET.
nagios:/home/fbulk# dig NS 7.31.96.in-addr.arpa @8.8.8.8 +short
ns1.mtcnet.net.
ns2.mtcnet.net.
ns1.netins.net.
nagios:/home/fbulk#