Totally Frickin' Wierd DSN Crap!!

[Kevin Darcy]

Brett Busch wrote:

> Okay, I am about to go insane with this stupid F&*#@(?? problem. Here it is:
>
> I have the domain "esubcontractor.com" that is hosted on our dns servers
> ns1.websourcemedia.com & ns2.websourcemedia.com. Up until Tuesday, the mail
> record was pointing to 209.29.205.67. Well, it was then changed to
> 209.247.122.205.

Huh? That's the address of ns1.websourcemedia.com. According to the
authoritative servers for the domain, the MX record for esubcontractor.com
points to mail.esubcontractor.com, which has the address 209.247.122.254. Is
that what you meant?

By the way, your servers only advertise ns1.websourcemedia.com as authoritative
for the zone, thus creating a single point of failure. It's generally
recommended to have at least 2 nameservers for each zone. The fact that the
delegations from "com" reflect 2 nameservers does *not* completely remove the
single-point-of-failure, since nameservers will override those delegations with
the data they get from an authoritative source.

> Now whenever I randomly select almost any DNS server and
> query it, I either get the old address of 209.29.205.67 or even stranger I
> will get the 209.247.122.205 one minute, then 209.29.205.67 the next??

The TTL on your A record appears to be an hour, but did you have a much higher
TTL on the record before it was changed? Looks like a stale record is slowly
expiring from (for example) ns.kivex.com's cache. It should be gone from there
within 2 days. Unfortunately, there's no way within the DNS protocol to
*force* a nameserver to flush a cache entry.

> As an
> even weirder problem, I recently created a db file for "esubcontractor.net"
> just yesterday and gave it the mail address of 209.247.122.254 and I'm
> getting the same problem with it. In other words, on our dns servers this
> record NEVER pointed to 209.29.205.67???

I'm getting the same results for that: the MX record points to
mail.esubcontractor.net which has the address 209.247.122.254. ns.kivex.com
seems to be answering the same way. Are you seeing something different?


- Kevin