Win95 machine not looking at 2nd and 3rd DNS

[Kevin Darcy]

nobody wrote:

> Hi All
>
> I have a Win 95 machine which is set up to look at 3 DNS servers.  The
> first is our internal, and the second and third are the ISP's.  If I
> look for a web address, the machine will query only the internal then
> give up (checked this with a packet sniffer).

This is working as it is supposed to. The nameserver list in a resolver is
only for finding a server to answer a query, it is not for getting a second
or third opinion on how a particular name should resolve. Once a nameserver
answers the query, then "misson accomplished"; no other nameserver in the
list is tried.

One thing this implies, among others, is that unless your ISP's DNS servers
have *full* knowledge of all of your internal zones, you shouldn't be
putting them in the resolver configuration of your internal clients at all.
Otherwise, if your regular nameserver is down, your clients will be
querying the ISP servers and might get bogus "no such name" responses even
for names that really exist!

> The internal DNS is sat on a linux box and serves subdomains beneath our
> internet registered domain (ie. registed domain foo.com, this box does
> london.foo.com and paris.foo.com).  The machine has no zone for root".".

You didn't say whether your clients need to resolve Internet names or not,
but assuming they do, you need to set up your nameserver to resolve those
names. If your nameserver has open access to other Internet nameservers,
then just configure it with the Internet root hints file. If it has no
direct access to Internet nameservers, or only restricted access, then
you'll probably have to use forwarding. Maybe your ISP would let you use
their DNS servers as forwarders?

> However, other machines I have seem to work fine (a linux box (not the
> name server), and an NT box.

Are their resolvers configured the same way?


- Kevin