Number of Standby Redo Logs on Physical Standby "Single Instance"

Dears,

  We have a setup like the following :

  RAC Production

  Node 1 : 2 Online Redo Log groups (Thread 1)

  Node 2 : 2 Online Redo Log Groups (Thread 2)

  DR : 2 online Redo Log Groups  (Single instance - Only we have one node)

  We need to create standby Redo logs on both sites.

  We have read that :

  - On production :

  Number of Standby redo logs must be = (Number of Online redo files +1) * 2

  Which means 6

  So we created :

- 3 SRL on thread 1

- 3 SRL on thread 2

  Question : What to do on DR?

  a) Shall we create them only 3 and all on thread 1?

  b) Or we have to create :

      3 SRL thread 1

      3 SRL thread 2