The DE Servers in High Availability mode require the system clocks on the two computers must to be within 1000 milliseconds (ms) of each other.
Release : 12.x
Component : CA WORKLOAD AUTOMATION DE (DSERIES)
The DE (dSeries) server uses OS time to calculate events and other artifacts.If there is considerable drift, the primary server will shutdown and a failover will take place.
This is to prevent any inconsistencies when the date/time field is updated in the database.
There is no recommended method for syncing OS clocks. For Linux use NTP to get the best performance or consult System Administrator.
For Windows, the host may use Active Directory or host (ESXi or Hyper-V) controller to sync time. It is always recommended to test and check which solution will work best.