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


Expected RPO can be set to 0-31 days, 0-23 hours, and 5-59 minutes.
If days and hours are not set, the Expected RPO is 15 minutes by default.
VSS is a framework provided by Microsoft for backing up and recovering applications. For SQL Server, the OceanStor BCManager Agent uses VSS to freeze or unfreeze application I/Os. After I/Os are frozen, the storage device starts replication or generating snapshots. Afterwards, the OceanStor BCManager Agent unfreezes write I/Os.
Configuration |
Description |
|---|---|
Default configuration |
Please select or create the resource pool at first, the system will establish clone replationship based on LUNs in resource pool. If a data protection service (for example, snapshots) has been created for a matched resource, the clone rela tionship 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 |
Manually select the resource pool, if not, click Create, the system will establish clone replationship based on LUNs in 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:
|
VSS is a framework provided by Microsoft for backing up and recovering applications. For SQL Server, the OceanStor BCManager Agent uses VSS to freeze or unfreeze application I/Os. After I/Os are frozen, the storage device starts replication or generating snapshots. Afterwards, the OceanStor BCManager Agent unfreezes 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.