Problems with load balancing on slave server

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I just recently upgraded from QuickDNS 2.2.1 to QuickDNS 3.5, and am
experiencing some very strange behavior.

When I create a new zone with a load balancing record, the domain looks fine
on the primary name server, and when testing with the load balancer, or with
my own manual test (taking down one server, etc) it works fine on the
primary name server.

However, when I look at the zone on the secondary name server, it has some
very strange entries - notably, there are two new entries made - both called
www, with a TTL of 300 (the TTL I set for the load balance record), with a
type of NS, and data of ns2.universalmac.com and ns.universalmac.com (my
primary and secondary name servers).

The load balance record is still there, however, if I look at it it has a
TTL value of 86400 (the default) instead of the 300 I set it to.

Load balancing for the secondary DNS server does not work at all, when
tested with the LB tester it always returns the secondary web server or non
load balanced result about 1 in 25.

Here's what's the primary zone looks like:

@ IN NS ns.universalmac.com.
@ IN NS ns2.universalmac.com.
@ IN MX 10 mail
@ IN MX 20 mail2
@ IN A 208.30.235.242
mail2 IN A 208.30.235.242
mail IN A 63.228.116.133

Load balance record:

Name: www
TTL: 300
Interval: 30
Hostlife: 60
Protocol: HTTP
Host addreses:
208.30.235.242 preference 100
63.228.116.133 preference 1

Here's what the secondary zone looks like:

@ IN NS ns.universalmac.com.
@ IN NS ns2.universalmac.com.
@ IN A 208.30.235.242
@ IN MX 10 mail
@ IN MX 20 mail2
www 300 IN NS ns2.universalmac.com.
www 300 IN NS ns.universalmac.com.
mail IN A 63.228.116.133
mail2 IN A 208.30.235.242

Load balance record:

Name: www
TTL: 86400
Interval: 30
Hostlife: 60
Protocol: HTTP
Host addreses:
208.30.235.242 preference 100
63.228.116.133 preference 1

Note the two odd www entries, only present on the secondary server.

The goal of load balancing in this case is purely for redundancy, which is
why I set the preference values to 100 and 1 - so that all my traffic will
got to 208.30.235.242 when it is up, if it's down, then the traffic should
go to 63.228.116.133. I could adjust these values if necessary, but
208.30.235.242 has significantly more bandwidth than 63.228.116.133 and a
much more powerful server.

There are currently 25 zones being served by these two DNS servers, pretty
much all of them look the same, and are having the same load balancing
problem.

After I configured all this, I read on this list that load balancing 20
servers might be a bad idea due to the overhead caused by the interval
checking.

However, all 25 of these servers combined generate less than 500 hits a day,
and are running on a 869Kbit internet connection on a PowerMac G3 400mhz B&W
running WebStar 4.4 for 208.30.235.242 and a 128Kbit internet connection on
a PowerMac 8100/80 running WebStar 4.3 for 63.228.116.133 at a remote
location.

208.30.235.242 is behind a IPNetRouter gateway. QuickDNS 3.5 runs on the
same box as IPNetRouter, I port mapped UDP 53 to enable QuickDNS to
communicate. The WebStar 4.4 server itself is on a separate box behind the
firewall.

Is the number of domains I am load balancing, or the IPNetRouter gateway
itself causing problems? I can reduce the need for load balancing records by
creating CNAMEs for as many hosts as possible, but I will still have 15 or
more domains and am going to be adding quite a few more in the near future.

Should I be using fully qualified names for load balancing records, or does
it make a difference?

I have also tried taking the gateway completely offline so that QuickDNS 3.5
is the only service running on 208.30.235.242 and then re-creating the zone
manually or with the assistant, either way the result is the same.
Therefore, I believe IPNetRouter is not getting in the way at this point.

The DNS server that load balancing works properly with, ns.universalmac.com,
properly pushes people to 208.30.235.242 99% of the time, and to
63.228.116.133 only on rare occasion, which is exactly what I want.
Therefore, I believe that IPNetRouter and my internal WebStar server
accessed at 208.30.235.242 are not part of the problem.

Which leaves me just with this strange anomaly on the secondary server at
208.30.235.242. Any ideas?

When I check out all 25 domains with DNS Expert Professional, they all come
out clean except for a need for a ptr record for the mail server at
63.228.116.133 (Just how big of a problem is that, anyways? Mail has been
consistently working for years without complaint)

Perhaps their is a better way to achieve the redundancy I am looking for?
It occurred to me that if I intentionally fragmented the zone data so that
the primary DNS server gave the primary web server IP's and the secondary
DNS server game the secondary web server IP's, I would get the result I am
looking for, but that seems like very bad policy.

Am I missing something here? How does the rest of the world deal with this
seemingly basic issue of 25 virtual domains that need to be able to
withstand a network outage? I plan on adding quite a few more domains over
the next couple months, and need a fully redundant connection system.

Thanks in advance for all the help, and sorry for such a lengthy post!

Noah

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