Creating a DR Star Trio Using LUNs

Prerequisites

• A local LUN has been created.
• Available storage pools exist on both the remote HyperMetro device and secondary asynchronous remote replication device.

Context

Create a DR Star trio on the local HyperMetro device.

The remote replication pair containing the local HyperMetro device is in the active state, and the other remote replication pair is in the standby state.

Procedure

1. Choose Services > Block Service > LUNs.
2. Select one or more desired LUNs, click Protect and choose Create DR Star.
3. Select a HyperMetro domain and remote device for asynchronous remote replication.
   1. In the HyperMetro Domain drop-down list, select a HyperMetro domain.

      You can click Create next to the drop-down list to create a HyperMetro domain.

   2. In the Remote Device in Async Remote Replication drop-down list, select a remote device.

   You can click Add next to the drop-down list to add a new remote device.

4. Configure parameters for HyperMetro and asynchronous remote replication pairs.
   1. Click Pair Parameters.

      The Pair Parameters page is displayed.

   2. Configure HyperMetro pair parameters.

      Table 3-5 describes the parameters.

      Table 3-5 HyperMetro pair parameters

      Parameter	Description
      Speed	Data synchronization speed of the HyperMetro pair. 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 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	Policy that determines how data is synchronized after a fault is rectified. Automatic: The system automatically synchronizes data. Manual: Data must be synchronized manually.
      Initial Sync	Initial synchronization mode of local and remote resources. Automatic: The system automatically synchronizes data between local and remote resources upon pair creation. Manual: Data must be manually synchronized between the local and remote resources upon pair creation.

   3. Configure parameters for asynchronous remote replication pairs.

      Table 3-6 describes the parameters.

      Table 3-6 Parameters for asynchronous remote replication pairs

      Parameter	Description
      Sync Type	Data synchronization mode between primary and secondary resources. Possible values are as follows: Manual: Data is 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 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.
      Interval	Synchronization interval for Timed wait after sync begins and Timed wait after sync ends. NOTE: This parameter is available only when Sync Type is set to Timed wait after sync begins or Timed wait after sync ends.
      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 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 values are as follows: Manual: Data is 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 values are as follows: Yes No
      Initial Sync	Initial synchronization mode of local and remote resources. 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 upon pair creation. NOTE: This parameter is valid only when local asynchronous remote replication is configured.

      The value ranges of remote replication parameters depend on the local device. When you select another local device in asynchronous remote replication, such parameters will be reset to their default values.

5. Create remote resources.
   1. In the HyperMetro Remote Storage Pool drop-down list, select the storage pool to which the remote HyperMetro resources belong.
   2. In the Async Remote Replication Remote Storage Pool drop-down list, select the storage pool to which the remote resources of asynchronous remote replication belong.
      • The storage system will automatically create remote LUNs in the HyperMetro Remote Storage Pool and Async Remote Replication Remote Storage Pool respectively. Then the system will create a HyperMetro pair and asynchronous remote replication pair for the specified LUNs, and use the pairs to create a DR Star trio.
      • Remote LUNs' capacities and application types are the same as those of the corresponding local LUNs. Their owning storage pools are HyperMetro Remote Storage Pool and Async Remote Replication Remote Storage Pool respectively. The other parameters take default values.

6. Click Advanced in the upper right corner and configure DR Star trio parameters based on service requirements.

   Table 3-7 describes the parameters.

   Table 3-7 Advanced DR Star trio parameters

   Parameter	Description
   Switchover Policy	Policy of switching the status of the two asynchronous remote replication pairs between Normal and Standby when a fault occurs. Possible values are as follows: Manual: When a fault occurs, you need to manually switch the status of the two asynchronous remote replication pairs. Automatic: When a fault occurs, the storage system automatically switches the status of the two asynchronous remote replication pairs based on specific fault conditions.
   Switchover Silent Time (Minutes)	When Switchover Policy is set to Automatic and a fault occurs, the storage system will automatically switch the status of the two asynchronous remote replication pairs if the fault persists after the switchover silent time expires. If the fault is rectified before the switchover silent time expires, the storage system will not perform the switchover. NOTE: This parameter is available only when Switchover Policy is set to Automatic.

7. Click OK and confirm your operation as prompted.