Creating a Synchronous Remote Replication CG

Prerequisites

• The local and remote storage systems support HyperReplication.
• Remote devices have been added.
• If Pair Creation is set to Manual:
  • 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.
• If Pair Creation is set to Automatic:
  • Health Status of the primary LUN must be Normal.
  • The primary LUN has not been equipped with any feature that conflicts with the HyperReplication feature.

Procedure

1. Choose Data Protection > Protection Entities > Protection Groups > Remote Replication CGs.
2. Click Create.

   The Create Remote Replication CG page is displayed.

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

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

3. Select Asynchronous as the remote replication mode for the remote replication CG.
4. From the Remote Device drop-down list, select the remote device with which you want to create a remote replication CG.

   If no device is available, click Add.

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

     Select the target storage pool for creating remote resources.

     • If the members in a protection group are LUN groups or LUN groups are used to create a CG (the storage system automatically creates a protection group for the LUN groups), the storage system automatically creates a remote LUN group and remote LUNs on a remote device for the LUN group and its member LUNs, and then creates remote replication pairs and a CG. Ensure that LUNs in the LUN group are not used to create remote replication pairs. If a remote LUN or a remote replication pair already exists, use manual creation mode to create remote replication pairs. Otherwise, a configuration conflict may occur.
     • If the members in a protection group are LUNs, the storage system automatically creates a remote LUN on a remote device for each local LUN, and then creates remote replication pairs and a CG.
   • Manual
     • If the members in a protection group are LUN groups or LUN groups are used to create a CG (the storage system automatically creates a protection group for the LUN groups), select the same number of LUN groups with the same capacity per LUN group and match the member LUNs between the local and remote devices. Ensure that LUN groups and member LUNs on the remote device are not mapped. Otherwise, a configuration conflict may occur.
     • If the members in a protection group are LUNs, select the LUNs with the same capacity. Ensure that the LUNs on the remote device are not mapped. Otherwise, a configuration conflict may occur.
     1. Click Configure.

        The Configure Pair page is displayed.

     2. Configure a remote replication pair.
        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.

6. Set the advanced properties of the remote replication CG. Select Advanced in the upper right corner.

   Table 3-10 describes the parameters.

   Table 3-10 Advanced properties of the remote replication CG

   Parameter	Description
   Speed	Data synchronization speed. Possible values 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. 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 takes the shortest period of time. This value is used when the service load is light. The speed is normally above 100 MB/s. Custom: User-defined 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 CG enters the To be recovered state. Automatic: The system automatically synchronizes data. The CG enters the Synchronizing state.
   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.
   Secondary LUN I/O Timeout	If data on the primary LUN fails to be written to the secondary LUN after the timeout period, the remote replication CG enters the disconnected state. NOTE: This parameter is available only when Replication Mode is set to Synchronous.
   Timeout Interval (Seconds)	The value ranges from 10 to 30 seconds. NOTE: This parameter is available only when Replication Mode is set to Synchronous and Set the remote I/O timeout threshold is enabled.

7. Click OK.

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