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# General Requirements

To use SLIP or PPP, you have to configure some basic networking features as described in the previous chapters, of course. At the least, you have to set up the loopback interface, and provide for name resolution. When connecting to the Internet, you will of course want to use DNS. The simplest option is to put the address of some name server into your resolv.conf file; this server will be queried as soon as the SLIP link is activated. The closer this name server is to the point where you dial in, the better.

However, this solution is not optimal, because all name lookups will still go through your SLIP/PPP link. If you worry about the bandwidth this consumes, you can also set up a caching-only name server. It doesn't really serve a domain, but only acts as a relay for all DNS queries produced on your host. The advantage of this scheme is that it builds up a cache, so that most queries have to be sent over the serial line only once. A named.boot file for a caching-only server looks like this:

               ; named.boot file for caching-only server
               directory                            /var/named

               primary       0.0.127.in-addr.arpa   db.127.0.0 ; loopback net
               cache         .                      db.cache   ; root servers

In addition to this name.boot file, you also have to set up the db.cache file with a valid list of root name servers. This is described toward the end of the Resolver Configuration chapter.