1. Administrator's Guide
  2. Managing Recovery Appliance
  3. Implementing Additional High Availability Strategies
  4. Implementing DR Failover to Downstream Recovery Appliance

Implementing DR Failover to Downstream Recovery Appliance

This section provides steps on how to configure a protected database for transparent failover of backup operations and redo transport to a downstream Recovery Appliance.

As part of disaster recovery, protected databases should failover to a downstream Recovery Appliance as the target for sending backup files and redo transport if the upstream Recovery Appliance is unavailable.

For sake of clarity, this examples makes the following assumptions:

  • If you have real time redo transport enabled, it receives an error and stops sending redo to the upstream Recovery Appliance. Within a minute, real time redo transport connects to the downstream Recovery Appliance and resumes sending redo there.
  • The name of the example protected database is CDB122DR. It is a Container Databases with One Pluggable Database.
  • The name of the example upstream Recovery Appliance is RAHADR1.
  • The name of the example downstream Recovery Appliance is RAHADR2.
  • A common VPC user called HADR_COMMON_VPCUSER was created on both Recovery Appliances and must use the same password on both.
  • A local VPC user called HADR_LOCAL_VPCUSER has been created on both Recovery Appliances but the password can be different between the two.
  • The replication server between RAHADR1 and RAHADR2 is using the VPC user REPUSER_FROM_HADR1.

When using a Data Guard setup that has primary and standby databases, they have the same dbid and dbname, so each must have a different db_unique_name. Use a unique control file autobackup format at primary and standby to guarantee uniqueness. The format can be specified by using RMAN configuration settings. Default Controlfile Autobackup Format: 

CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE SBT_TAPE TO '%F';

Add db_unique_name to the default format for both primary and standby databases: 

CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE SBT_TAPE TO '<db_unique_name>_%F';

The db_unique_name is obtained from from v$database. 

select db_unique_name from v$database;