Mysterious DNS Problem

[Mark_Andrews at isc.org]

> Well, at least it is mysterious to a rookie like me.
> 
> I have registered 3 DNS servers with the internic. However, some ISPs have
> the third DNS addresses in their cache, which point to a mirror site. I
> waited until the cache was cleared (TTL value expired), and when I queried
> the ISPs name server, the #3 DNS value was there again.
> 
> Why does it not cache DNS1 or DNS2? Even though I know they were not down?
> 
> For example the A record for WWW.MYDOMAIN.COM is 255.255.255.1 on DNS1 and
> DNS2. The A record for WWW.MYDOMAIN.COM for DNS3 is 255.255.255.2.
> 
> If you were to use home.net's DNS server, you will be sent to 255.255.255.2.
> Why doesnt it cache the first value?

	mydomain.com has 4 dns servers not 3.  The nameservers
	names are ns1.mydomain.com, ns2.mydomain.com, ns3.mydomain.com
	and ns4.mydomain.com.  The IP address for www.mydomain.com
	is 209.153.199.62 from all of these servers.

	Why does every rookie expect to get an answer when they hide
	the domain names / IP addresses involved.  You have a problem,
	do you hide symtoms when you go to your doctor or to the mechanic
	to fix your car.  How do you expect us to help you unless we
	can actually identify the problem.

	Mark
> 
> Thanks,
> 
> Mo
> 
> 
> 
> 
> 
--
Mark Andrews, Internet Software Consortium
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka at isc.org