Creating an Asynchronous Remote Replication Pair

Prerequisites

• The local and remote storage systems support remote replication.
• The remote device has been added. A secondary LUN has been created on the remote device and cannot be mapped to the host.
• The capacity of the primary LUN must be the same as that of the secondary LUN.
• Health Status of primary and secondary LUNs is Normal.
• Primary and secondary LUNs have not been equipped with any feature that conflicts with the HyperReplication feature.

Procedure

1. Choose Data Protection > Protection Entities > LUNs > Remote Replication Pairs.
2. Click Create.

   The Create Remote Replication Pair page is displayed on the right.

   You can also perform the following operations to go to the Create Remote Replication Pair page:

   • Choose Services > Block Service > LUNs.
     • Select the desired LUN and choose Protect > Create Remote Replication.
     • Click More on the right of the desired LUN and select Create Remote Replication.
   • Choose Data Protection > Protection Entities > LUNs > LUNs.
     • Select the desired LUN and click Create Remote Replication.
     • Click More on the right of the desired LUN and select Create Remote Replication.
     • Click the name of the desired LUN. In the upper right corner of the page that is displayed, click Operation and select Create Remote Replication.

3. Select the LUNs for which you want to create remote replication pairs in the Available LUNs area and click to add them to the Selected LUNs area.

   When you choose Services > Block Service > LUNs or Data Protection > Protection Entities > LUNs > LUNs to create a remote replication pair, you need to click and then select desired LUNs.

4. Click Next.
5. Select Asynchronous as the remote replication mode for the remote replication pair.
6. From the Remote Device drop-down list, select the remote device with which you want to create a remote replication pair.

   If no remote device is available, click Add.

7. Specify Pair Creation. Possible values are Automatic and Manual.
   • Automatic

     Select the target storage pool for creating remote resources.

     If Pair Creation is set to Automatic, the storage system automatically creates a remote LUN in the storage pool of the remote device and creates a remote replication pair for the selected local and remote LUNs.

   • Manual
     1. Click Configure in Remote Replication Pairs.

        The Configure Pair page is displayed.

     2. Configure a remote replication pair.
        • If the PG contains LUNs:
          1. In the Local Resources area, select the local resource.
          2. In the Remote Resources area, select the remote resource.
          3. Click Add to Pair. The created pair is displayed in the Remote Replication Pairs list.
        • If the PG contains LUN groups:
          1. From the Remote Resources drop-down list, select the remote resource for which you want to create a remote replication pair.
          2. In the Local Resources area, select the local resource.
          3. In the Remote Resources area, select the remote resource.
          4. Click Add to Pair. The created pair is displayed in the Remote Replication Pairs list.

8. Set the properties of the remote replication pair.
   Table 3-5 describes the parameters.

   Table 3-5 Remote replication pair parameters

   Parameter	Description
   Sync Type	Determines how data is synchronized between primary and secondary resources. Possible options are as follows: Manual: Data must be manually synchronized between primary and secondary resources. Timed wait after sync begins: The system starts timing after the last 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 as soon as the latest synchronization ends. After the time specified in Interval is reached, the system automatically starts data synchronization between primary and secondary resources again. NOTE: This parameter is available only when Replication Mode is set to Asynchronous.
   Interval	Synchronization interval for Timed wait after sync begins and Timed wait after sync ends. NOTE: This parameter is available only when Replication Mode is set to Asynchronous and Sync Type is set to Timed wait after sync begins or Timed wait after sync ends.

9. Set the advanced properties of the remote replication pair. Select Advanced in the upper right corner.

   Table 3-6 describes the parameters.

   Table 3-6 Advanced properties of a remote replication pair

   Parameter	Description
   Standby	Specifies whether the remote replication pair is standby. NOTE: This parameter is available only when Replication Mode is set to Asynchronous. A standby asynchronous remote replication pair functions as the secondary resource in a DR Star trio and can be restored to the normal state only after a DR Star trio fault or manual switchover. A standby asynchronous remote replication pair can be created only when a synchronous remote replication pair or HyperMetro pair and a non-standby remote replication pair exist in a DR Star trio.
   Speed	Data synchronization speed. Possible options are as follows: Low: Data synchronization takes a relatively long period of time. This value is used when the service load is heavy. The speed is normally from 0 MB/s to 5 MB/s. Medium: Data synchronization takes a relatively short period of time. This value is used when the service load is relatively heavy. The speed is normally from 10 MB/s to 20 MB/s. High: Data synchronization takes a short period of time. This value is used when the service load is relatively light. The speed is normally from 20 MB/s to 70 MB/s. Highest: Data synchronization is completed in the shortest period of time. This value is used when the service load is light. The speed is normally above 100 MB/s. Custom: customized data synchronization speed. The value ranges from 1 MB/s to 1024 MB/s.
   Recovery Policy	Determines how data is synchronized after an internal I/O error or a replication link fault is rectified. Possible options are as follows: Manual: Data must be synchronized manually. The pair enters the To be recovered state. Automatic: The system automatically synchronizes data. The pair enters the Synchronizing state.
   Link Compression	Indicates whether to enable link compression for data synchronization between local and remote resources. Enabling link compression saves the bandwidth of replication links and improves replication performance. Possible options are as follows: Yes No NOTE: This parameter is available only when Replication Mode is set to Asynchronous.
   Initial Sync	Initial synchronization mode of local and remote resources. If Pair Creation is set to Automatic, the value can be: 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. If Pair Creation is set to Manual, the value can be: In a scenario where data is inconsistent: 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. In a scenario where data is consistent, synchronization is not required.

10. Click Next.

    A summary is displayed.

11. Confirm the information about the created remote replication pair and click OK.

    If Speed is set to Highest or Pair Creation is set to Manual, confirm your operation as prompted.