I am a newbie to data guard.
Wel come to the data guard
1) Unless using the real time apply feature, standby redo logs must be archived before the data can be applied to the standby database. Am I correct in my understanding?
Not uderstand your question.
2) Can we keep standby database in higher version(11i) and primary database in 10g?
No. Both the version should be same.
3) Do I need to left blank LOG_ARCHIVE_DEST_2 parameter on Standby Database init parameter?
Yes.Until you dont required to send archived log from standby database to any other database. If you have cascaded setup then you would required to set the parameter as required.
4) Can we face any problem if we have different LOG_ARCHIVE_FORMAT on the primary and standby site?
Yes. We should keep default log format or shourl be same.
Waiting for your valuable reply.