2.5 Configuring Time Synchronization for the Cluster
Oracle Clusterware requires the same time zone setting on all cluster nodes.
About Cluster Time Synchronization
For the Microsoft Windows operating system, there are three different methods you can use to synchronize the time between the nodes of your cluster.
Understanding Network Time Requirements
Oracle Clusterware 12c Release 1 (12.1) is automatically configured with Cluster Time Synchronization Service (CTSS).
Configuring the Windows Time Service
The Windows Time service (W32Time) provides network clock synchronization on computers running Microsoft Windows.