Network Time Protocol (NTP)

Network Time Protocol (NTP) is a protocol for synchronizing the clocks of computers in a network of computers. If you were to set up a RAC environment, one of the requirement is to synchronize the clock time of all your RAC nodes to avoid unnecessary node eviction. Time difference of more than 15 mins among nodes may cause node evictions. Also the trace file analysis and GV$ view analysis may not be accurate if the time is not synchronized among nodes.



Configuring NTP:

NTP configuration has 3 files in the /etc folder

ntp.conf
ntp.drift
ntp.trace


Add the names of the nodes in the ntp.conf file along with the names of drift and trace file as shown in the picture below.



cmsprod1 and cmsprod2 are the node names..



Add this information in all the nodes participating in the cluster.
Leave the drift and trace files as it is..

Thanks.