Test ext NTP

This is a test case to test NTP. The /etc/ntp.conf file contains all the NTP server list. Verify that ntpq can display status (sudo ntpq -p).

On the worker nodes, ntp.conf servers should point to 3 controller nodes. Ensure they get selected as time source and that time reaches synchronization

On each of the 3 controller nodes, ntp.conf should point to upstream NTP server and other controller nodes , which is the primary time source. Ensure they get selected as time source and that time reaches synchronization.

1. One test can be, a) stop ntpd service, b)change system time c) start ntpd service and see that the time gets synchronized.

2. Another test can be to find the maximum time difference between stop and start beyond which time will not synchronize.