Running pppd
When you want to connect to the Internet through a PPP link, you have
to set up basic networking capabilities, such as the loopback device
and the resolver. Both have been covered in Chapter 5, and Chapter 6. You can
simply configure the name server of your Internet Service Provider in
the /etc/resolv.conf
file, but this will mean
that every DNS request is sent across your serial link. This situation is not
optimal; the closer (network-wise) you are to your name server, the
faster the name lookups will be. An alternative solution is to
configure a caching-only name server at a host on your network. This
means that the first time you make a DNS query for a particular
host, your request will be sent across your serial link, but every
subsequent request will be answered directly by your local name
server, and will be much faster. This configuration is described in Chapter 6, in
Section 6.3.4.”
As an introductory example of how to establish a PPP connection with
pppd, assume you are at vlager again. First, dial in to the PPP
server c3po and log in to the
ppp account. c3po will execute its PPP driver. After
exiting the communications program you used for dialing, execute the
following command, substituting the name of the serial device you used
for the ttyS3
shown here:
# pppd /dev/ttyS3 38400 crtscts defaultroute
This command flips the serial line ttyS3
to the
PPP line discipline and negotiates an IP link with c3po. The transfer speed used on the serial port will ...
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