Enable NTP on the Cluster and on the Browser Host
The clocks of all the nodes in your cluster and the machine that runs the browser through which you access the Ambari Web interface must be able to synchronize with each other.
To install the NTP service, run the following command on each host:
yum install -y ntp
To set the NTP service to auto-start on boot, run the following command on each host:
systemctl enable ntpd
To start the NTP service, run the following command on each host:
systemctl start ntpd