Oracle Clusterware 11g release 2 (11.2) is automatically configured with Cluster Time Synchronization Service (CTSS). This service provides automatic synchronization of all cluster nodes using the optimal synchronization strategy for the type of cluster you deploy. If you have an existing cluster synchronization service, such as NTP, then it will start in an observer mode. Otherwise, it will start in an active mode to ensure that time is synchronized between cluster nodes. CTSS will not cause compatibility issues.Regards,
The CTSS module is installed as a part of Oracle Grid Infrastructure installation. CTSS daemons are started up by the OHAS daemon (ohasd), and do not require a command-line interface.