Creating a Remote Replication Pair

Prerequisites

When creating a remote replication pair, ensure that the secondary namespace has not been used (data, snapshots, quotas, or dtrees are not created in the secondary namespace) and the DPC function of the secondary namespace is disabled. Otherwise, the remote replication pair cannot be created.

Procedure

1. Choose Data Protection > Protection Entity > Namespace > Remote Replication Pair.
2. Select a desired account from the Account drop-down list in the upper left corner.
3. Click Create.

   The Create Remote Replication Pair dialog box is displayed.

4. In the Available Namespaces area on the left, select one or more desired namespaces for which you want to create remote replication pairs and they are added to the Selected Namespaces area on the right.
   

   Namespaces for which the cross-site DR feature has been configured cannot be used to create a remote replication pair.

5. Click Next.
6. From the Remote Device drop-down list, select the remote device with which you want to create a remote replication pair.
7. Configure remote replication pairs.
   1. Click Configure.

      The Configure Pair page is displayed.

   2. Configure remote replication pairs.
      1. In the Local Resources area, select the local namespace.
      2. In the Remote Resources area, select the remote namespace. The name of the remote namespace must be the same as that of the local namespace.
      3. Click Add to Pair. After the pair is added successfully, the pair will be displayed in the list below.
      4. After all local resources are configured as pairs, click OK.

8. Set properties of the remote replication pair. Table 1 describes related parameters.

   Table 1 Remote replication pair parameters

   Parameter	Description
   Sync Type	Data synchronization mode of the primary and secondary resources. Possible values are: Manual: Data must be manually synchronized between primary and secondary resources. Timed wait after sync begins: The system starts timing as soon as the latest synchronization begins. After the time specified in Interval is reached, the system automatically starts data synchronization between primary and secondary resources again. NOTE: If the last synchronization has not finished after the time specified in Interval is reached, the system performs the next synchronization after the last synchronization finishes. Timed wait after sync ends: The system starts timing after the last synchronization finishes. After the time specified in Interval is reached, the system automatically starts data synchronization between primary and secondary resources again. Specific time policy: The system automatically synchronizes data between primary and secondary resources based on a specific time policy.
   Interval	Synchronization interval for Timed wait after sync begins and Timed wait after sync ends. [Value range] The interval is an integer ranging from 1 to 1440 when minutes is used as the unit. The value is an integer ranging from 30 to 59 when seconds is used as the unit. NOTE: This parameter is available only when Sync Type is set to Timed wait after sync begins or Timed wait after sync ends.
   Time Policy	Specific time policy: The system automatically synchronizes data between primary and secondary resources based on a specific time policy. [Value range] Weekly: Data synchronization begins at a specific time on a specific day. Its value ranges from 00:00 on Monday to 23:59 on Sunday. Daily: Data synchronization begins on every day. Its value ranges from 00:00 to 23:59. Hourly: Data synchronization begins in every hour. Its value is an integer ranging from 0 to 59. NOTE: This parameter is available only when Sync Type is set to Specific time policy.
   Copy Snapshot Retention in Secondary Resource	Retention policy of copy snapshots. Possible values are: Do not retain: No copy snapshot will be created in secondary resources after pair synchronization. Retain: The system will create a copy snapshot in each secondary resource each time after pair synchronization to capture the data state of the primary resources at the time when pair synchronization starts. NOTE: A copy snapshot created under a copy snapshot retention policy in secondary resource is a replication snapshot. To view replication snapshots, choose Data Protection > Protection Entity > Namespace > Snapshot and filter snapshots by Type on DeviceManager.
   Copy Snapshots Retained in Secondary Resource	Number of copy snapshots retained in the secondary resource. When the number of copy snapshots at the secondary end exceeds the value of this parameter, the system deletes the earliest copy snapshots by default. [Value range] 1~512 NOTE: This parameter is available only when Copy Snapshot Retention in Secondary Resource is set to Retain. The name of a copy snapshot is prefixed by rep_copy.

9. Set the advanced properties of a remote replication pair.
   1. Select Advanced in the upper right corner.
   2. Configure advanced remote replication pair properties. Table 2 describes related parameters.

      Table 2 Advanced remote replication pair parameters

      Parameter	Description
      Speed	Data synchronization speed of the remote replication pair. The value ranges from 1 MB/s to 10,240 MB/s (or 1024 KB/s to 10,485,760 KB/s). During initial synchronization, the recommended rate is 100 MB/s or higher. During incremental synchronization, if the service load is heavy, the recommended rate is 0 MB/s to 20 MB/s. During incremental synchronization, if the service load is relatively heavy, the recommended rate is 20 MB/s to 70 MB/s. During incremental synchronization, if the service is idle, the recommended rate is 100 MB/s or higher. The default value is 32 MB/s.
      Recovery Policy	Whether the remote replication pair automatically synchronizes data after an internal I/O fault or a replication link fault of the remote replication is rectified. The default value is Automatic. [Value range] Automatic: The system automatically synchronizes data. The pair enters the Synchronizing state. Manual: Data must be synchronized manually. The pair enters the To be recovered state.
      Initial Sync	Initial synchronization mode of local and remote resources. The default value is Automatic. [Value range] Automatic: The system automatically synchronizes data of the primary resource to the secondary resource upon pair creation. Ensure that data of the secondary resource is no longer needed or has been backed up. Manual: Data of the primary resource must be manually synchronized to the secondary resource. For details, see Synchronizing a Remote Replication Pair.

10. Click Next.

    A summary is displayed.

11. Confirm information about the created remote replication pair and click OK.
12. Confirm your operation as prompted.