Installing and Administering Internet Services

220 Chapter 7
Configuring NTP
Configuration
configured on its client systems. For example, if Penelope is to be a client
of Bonita, you configure the name or address of Bonita on Penelope. You
do not need to configure Penelope as a client on Bonita.
Figure 7-9 Example Configurations
Configuring a Driftfile
xntpd computes the error in the frequency of the clock in the local host.
It usually takes xntpd a day or so after it is started to compute a good
estimate of the frequency error. The current value of the frequency error
may be stored in a driftfile. The driftfile allows a restarted xntpd to
reinitialize itself to the estimate stored in the driftfile, saving about a
day’s worth of time in recomputing a good frequency estimate. You
specify the path and name of the driftfile.
NOTE xntpd should be operated on a continuous basis. If it is necessary to stop
xntpd, the interval when it is not running should be kept to a minimum.
To specify the driftfile, define the keyword driftfile, followed by the
name of the file in which the frequency error value is to be stored. The
recommended location for the driftfile is /etc/ntp.drift. The
following is an example of a driftfile statement:
driftfile /etc/ntp.drift
Gordo
Penelope Golden
Hugo
server bonita
peer golden
broadcast 193.100.255.255
server gordo
peer penelope
broadcast 193.100.255.255
broadcastclient yes
Bonita
server 127.127.4.1server 127.127.4.1
external
clock
external
clock