Setting up NTP server pool

You must set up an NTP server pool to configure time synchronization across Cassandra nodes.

1. Obtain two physical machines with static IP addresses.
2. Complete the following tasks on each machine:
   1. To stop the NTPD service, type service ntpd stop.
   2. Open the /etc/ntp.conf file for editing.
   3. In the ntp.conf file, add references to your higher stratum NTP servers:

      server <higher stratum server 1> iburst prefer

      server <higher stratum server 2> iburst

      Remove all other server references. These higher stratum servers can be public NTP servers or other servers in your organization.

   1. Save the ntp.conf file.
   2. To force an initial sync up, type ntpd -gq.
   3. To restart the NTPD service, type service ntpd start.
   4. To ensure that the service runs on start-up, type chkconfig ntpd on.