If the old active database is undamaged, you can bring it back online as the new standby database by entering:
resume connection to data_server.database
where data_server.database is the physical database name of the old active database.
You may need to resolve paper-trail transactions in the database in order to avoid duplicate transactions. Depending on your applications, you may need to do this before you bring the old active database back online as the new standby database.
Because paper-trail transactions must be re-executed in the new active database, you must prepare the new standby database so that it can receive the transactions again when they are delivered through the replication system.
To resolve the conflicts, you can:
Undo or reverse the duplicate transactions in the new standby database, or
Ignore the duplicate transactions and deal with them later.