CIS 238 - UNIX System Administration s1

CIS 238 - UNIX System Administration

Lab Exercise #12:Network Time Protocol

1) Make sure the ntp package is installed.

2) Make sure the system-config-date package is installed

3) Issue command: ntpdate –u (time-a.nist.gov) – 3 times

4) Go to Administration, Time and Date

5) Set the Central (US) Timezone

6) On the NTP Tab

- set the NTP Service to start

- add servers 172.27.xx.xx time-a.nist.gov

- specify synch time before starting service

- enable local broadcast

7) Review /etc/ntp.conf, www.ntp.org, the /etc/ntp directory

8) Modify ntp.conf as follows:

- specify servers:

server time-a.nist.gov # A stratum 1 server

server 131.107.2.200 # A stratum 2 server

- Restrict server access

restrict time-a.nist.gov mask 255.255.255.255 nomodify notrap noquery

- restrict network access:

restrict 131.107.2.0 mask 255.255.255.0 notrust nomodify notrap

restrict 127.0.0.1

9) Restart the NTP service

- Issue the ntpq –p command, review output

10) Read the MAN page on “hwclock”

Update the ckock chip setting with “hwclock –w”