DNS Conundrum

[boden]

I run a 12 machine Win2000 network in my home. Two servers (Win2000 Pro
Server, SP4), one with DNS implemented on it and 10 workstations running
Win2000 Pro, SP4. These machines are connected through an unmanaged
switch and connect to my ISP through a D-link RT311 Router. All
machines point to the D-Link Router first as the DNS source, and then to
the internal server on which DNS is implemented (for internal machine
name resolution). The D-Link server points to my ISP's DNS server first
and then to their backup DNS server which is operated by AT&T. The
connection to my ISP is through a Paradyne DSL modem.

My problem is that sometimes, not always, when I enter a literal domain
name in the URL bar of Netscape 7.01 I will connect normally, other
times I will get a message saying that the name can't be resolved.
Hours later I may be able to connect. If I ping to the literal domain
name and obtain its numeric IP address and enter that into the URL bar I
will connect immediately.

I can't figure out what is happening and my ISP has tried numerous times
to determine what is happening without success.

Any and all ideas will really be appreciated.

Boden

 

[Frankster]

Intermittent probs like this are the result of a DNS mis-config.

In TCP/IP Properties of the NIC, all DNS client PCs (including your servers)
should point only the internal DNS you are running yourself (not your ISPs
DNS). The internal DNS server should point to itself.

Your internal DNS server should be configured with a forwarder to your
internal router's IP.

In TCP/IP Properties your router should have your ISP provided external DNS
servers.

That will fix it.

-Frank

 

[boden]

Thanks for the help. I added a forwarder, and pointed all boxes to just
the server running DNS and all is working as it should be.

Boden

 

[Frankster]

Great! Glad you got it working. This is probably the most common DNS
misconfiguration mistake (i.e. using the ISP-provided DNS server IPs in the
client's config.).

-Frank