Собственно сабж. Провожу предварительную проверку перед установкой, вылетает prvg-13606
Details:
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PRVG-13606 : chrony daemon is not synchronized with any external time source on node "oracle2".  - Cause:  The output of the command ''chronyc sources'' executed on the indicated node did not list any external chrony daemon synchronization time source. The values of the mode and state columns in the command output reported that the chrony daemon is either not synchronized with any time source or is synchronized with a locally connected reference clock.  - Action:  Examine the output of the command ''chronyc sources''. Modify the chrony configuration to use one or more appropriate external time sources, or correct any problems accessing the currently configured external time sources. Rerun the command ''chronyc sources'' to confirm that the chrony daemon running on the indicated node is now synchronized with at least one external time source, and then retry the operation.
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PRVG-13606 : chrony daemon is not synchronized with any external time source on node "oracle2".  - Cause:  The output of the command ''chronyc sources'' executed on the indicated node did not list any external chrony daemon synchronization time source. The values of the mode and state columns in the command output reported that the chrony daemon is either not synchronized with any time source or is synchronized with a locally connected reference clock.  - Action:  Examine the output of the command ''chronyc sources''. Modify the chrony configuration to use one or more appropriate external time sources, or correct any problems accessing the currently configured external time sources. Rerun the command ''chronyc sources'' to confirm that the chrony daemon running on the indicated node is now synchronized with at least one external time source, and then retry the operation.

В 11м RAC вылетала подобная ошибка, при работающей но несконфигуренной службой NTP. Достаточно было просто ее отключить, тогда кластер для синхронизации использовал внутренний механизм. Может быть кто нить знает, в 12м что то поменялось на этот счет?

ну в общем сам спросил, и сам ответил.

стопим службы ntpd и chronyd, переименовываем их конфиги, и у нас синхронизация начинается по Oracle Cluster Time Synchronization Service