Data Guard Not Applying Logs After RAC Standby Database Restarted

11.2.0.4 RAC standby database is not applying archivelogs after instances are all restarted.  It is configured in Data Guard management.

After investigation, there is nothing special, but only “PreferredApplyInstance” is configured for RAC node1 ‘STBTEST1’.

Original :

PreferredApplyInstance ='STBTEST1'

Modify “PreferredApplyInstance” to empty:

PreferredApplyInstance=''

Restarted RAC standby database instances , all archivelogs are applied to database from the node which is chosen randomly by Data Guard.