Do both servers have to be up to resolve?

[David Cost]

Ran into a curious situation with one of three domains not resolving DNS and
wondering if it is due to the secondary nameserver:

All three have their primary server as ns1.granitecanyon.net
ONE of them has realdns as the secondary at: dns.realdns.com 167.160.249.51,
the other two use granite canyon for secondary.

When I changed zone data on the above DNS servers to reflect an IP address
change of our local webserver, the latter two worked OK, but when changing
the real DNS zone, the domain got deleted from their server and could not be
restored (they are not responding to email right now). However it is still
listed as the secondary server on internic. This domain does not resolve any
longer however, although nslookup shows granite canyon's server has the
correct IP, etc.

I have put-off changing the secondary back to GraniteCanyon because RealDNS
as the secondary has been a good strategy, there have been a number of times
that GC went down and our one site that uses the alternative secondary was
the only one working, and I'm hoping that eventually they will answer my
email, I have been unable to figure out even how to make payment to them for
their service. .

Question is: because the zone for the domain that no longer works no longer
exists on the secondary nameserver, would that account for the Domain
returning a DNS error when you try to find it with a browser even though the
primary nameserver is working and configured correctly? In other words do
zones physically have to exist on both nameservers in order to get it to
resolve via one of them without an error?

Best Regards, -DC