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6.5 Sample Resolver Configurations
Let's go over what
some Windows Server 2003 resolver configurations look like on real
hosts. Resolver configuration needs vary depending on whether or not
a host runs a local name server, so we'll cover both
cases: hosts using remote name servers and hosts running name servers
locally.
6.5.1 Remote Name Server
We, as the
administrators
of movie.edu, have been asked to configure a
professor's new workstation, which
doesn't run a name server. Deciding which domain the
workstation belongs in is easy: there's only
movie.edu to choose from. However, the professor
is working with researchers at Pixar on new
shading algorithms, so perhaps it'd be wise to put
pixar.com in her workstation's
list of DNS suffixes to append.The new workstation is on the 192.249.249.0 network, so the closest
name servers are wormhole.movie.edu
(192.249.249.1) and terminator.movie.edu
(192.249.249.3). As a rule, you should configure hosts to first use
the closest name server available. (The closest possible name server
is a name server on the local host; the next closest is a name server
on the same subnet or network.) In this case, both name servers are
equally close, but we know that wormhole is
bigger (it's a faster host, with more capacity).Since this particular professor is known to get awfully vocal when
she has problems with her computer, we'll also add
terminator.movie.edu (192.249.249.3) as a backup
name server. That way, if wormhole is down for
any reason, the professor's workstation can still
get name service (assuming terminator and the
rest of the network are up).Figure 6-13 shows what her
workstation's resolver configuration will look like.
Figure 6-13. Example resolver configuration
6.5.2 Local Name Server
Next, we have to configure
the
university mail hub, postmanrings2x, to use DNS.
postmanrings2x is shared by all groups in the
movie.edu domain. We've
recently configured a name server on the host to help cut down the
load on the other name servers, so we should make sure the resolver
queries the name server on the local host first.If we decide we need a backup name servera prudent
decisionwe can add a name server to the DNS server addresses, in order of use field.
Whether or not we configure a backup name server depends largely on
the reliability of the local name server. A robust name server
implementation will keep running for longer than some operating
systems, so there may be no need for a backup. If the local name
server has a history of problems, thoughsay it hangs
occasionally and stops responding to
queriesit's prudent to add a backup name
server.To add a backup name server, we just list the local name server first
in the list of DNS suffixes to append and then list one or two backup
name servers. Since we'd rather be safe than sorry,
we're going to add two backup name servers.
postmanrings2x is on the 192.249.249.0 network,
too, so terminator and
wormhole are the closest name servers to it
(besides its own). The final configuration is shown in Figure 6-14.
Figure 6-14. Another example resolver
configuration
