This section describes how to create a protected group at the production site for IBM DB2 databases that need DR protection. After the protected group is created, the system automatically matches suitable protection policies for the protected group.
One protected group can only contain IBM DB2 databases that belong to the same instance.
The protected objects belonging to one protected group reside on the same storage device. Each protected object occupies independent storage LUNs or volumes.


If days and hours are not set, the Expected RPO is 15 minutes by default.
Consistency between DB2 databases is ensured by hanging write I/Os. After write I/Os are hung, the storage device starts replication or generates snapshots. Afterwards, the system instructs the Agent to restore the write I/Os of the database.
Configuration |
Description |
|---|---|
Default configuration |
The system matches resources with the same capacity, owning controller, and normal status from the storage resources used by protected objects. The system establishes a clone relationship based on the matched resources. If a data protection service (for example, snapshots) has been created for a matched resource, the clone relationship may fail to be created. The protected object (clone primary LUN) has a one-to-one relationship with the matched resource (clone secondary LUN). |
Manual configuration |
You need to manually select a resource pool. If no resource pool exists in the system, click Create to create a resource pool. After you select or create a resource pool, the system establishes a clone relationship based on LUNs in the created resource pool. The protected object (clone primary LUN) has a one-to-one relationship with the matched resource (clone secondary LUN). |


If days and hours are not set, the Expected RPO is 15 minutes by default.

Retention Policy |
Description |
|---|---|
Latest duplicate |
The number of duplicates cannot exceed the maximum number of snapshots that can be taken for a storage resource such as a LUN or file system. |
Duplicate retention |
The duplicate retention policy defines the retention policy of duplicates generated during the protected group protection. When the system starts duplicate maintenance, expired and invalid duplicates will be deleted based on the duplicate retention policy. By default, the time to maintain duplicates is the 39th minute of every hour. You can set the minimum number of duplicates to be retained. The system will not delete valid duplicates until the number of invalid duplicates exceeds the minimum number of duplicates you set.
When determining the number of retained duplicates, consider the following:
NOTE:
For example, if the current time is 2017/4/11 08:40:00, configure the protected group as following:
If the protected group is under the automatically scheduled protection for a long time, the duplicates retained are as follows after the duplicate maintenance is complete at the current time:
NOTE:
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Consistency between databases is ensured by hanging write I/Os. After write I/Os are hung, the storage device starts replication or generates snapshots. Afterwards, the eReplication Agent renews write I/Os.
If a recovery plan has been created for a protected group, you can refresh protected objects only when the recovery plan status is Ready, Clear completed, Rollback completed, or Reprotection completed.
If a protected group uses backup (SAN), a snapshot copy being used by a recovery plan cannot be deleted. To delete such a snapshot copy, wait until the recovery plan finishes clearing.