Option 2: Use log_archive* Parameters to Configure Real-Time Redo Transport

This task enables manually changes several log_archive* parameters that establish failover of real-time redo transport from the upstream to the downstream Recovery Appliance.

• Log into sqlplus as rasys/ra and change several parameters with respect to the primary databases, connection identifiers for the Recovery Appliances, network timeouts, and maximum number of failures. In the end, enable the configuration changes.

  $ sqlplus rasys/ra
  
  SQL> alter system set log_archive_config =
  'dg_config=(cdb122dr,rahadr1,rahadr2)';
  
  SQL> alter system set log_archive_dest_2='service=dr_rahadr1 ASYNC NOAFFIRM
  delay=0 optional compression=disable max_failure=1 max_connections=1
  reopen=10 db_unique_name=rahadr1 net_timeout=8 group=1 priority=1
  valid_for=(online_logfile,all_roles)';
  
  SQL> alter system set log_archive_dest_3='service=dr_rahadr2 ASYNC NOAFFIRM
  delay=0 optional compression=disable max_failure=1 max_connections=1
  reopen=300 db_unique_name=rahadr2 net_timeout=8 group=1 priority=2
  valid_for=(online_logfile,all_roles)';
  
  SQL> alter system set log_archive_dest_state_2=enable;
  
  SQL> alter system set log_archive_dest_state_3=enable;

Note:

If Redo Transport does not start, then you may need to bounce the protected database. For a RAC database, this can be done in a rolling fashion.