Restrictions for multiple standby databases

There are a number of restrictions that you should be aware of if you are planning to deploy multiple HADR standby databases.

The restrictions are as follows:

• You can have a maximum of three standby databases: one principal standby and up to two auxiliary standbys. The exception is for Db2® pureScale® environments, in which you can only have one standby (the principal standby).
• Only the principal standby supports all the HADR synchronization modes; all auxiliary standbys will be in SUPERASYNC mode.
• IBM® Tivoli® System Automation for Multiplatforms (SA MP) support applies only between the primary HADR database and its principal standby. The exception is for Db2 pureScale environments, in which SA MP only manages the local cluster and does not automate failover to the standby cluster
• The hadr_target_list database configuration parameter must be set on all the databases in the multiple standby setup. Each standby must include the primary in its hadr_target_list setting.