DR Testing in the DR Center

This section describes how to test data in the DR center. DR tests are implemented by snapshot mapping in the DR center. The test is to verify that data or snapshots replicated to the DR center are available. The test process has no adverse impact on the production site. After a test is complete, the test data generated at the DR site needs to be cleared and resources need to be restored to the status before the test to facilitate future DR or planned migration.

Prerequisites

The production center communicates with the DR center properly.
The datastore name cannot contain Chinese characters.
At least one recovery plan has been created on eReplication.
For details about requirements on storage licenses for the tested recovery plan, see Checking License Files.
For database applications, all check items related to DR environments are passed. For details about the check items, see Oracle, IBM DB2, Microsoft SQL Server, and Microsoft Exchange Server, SAP HANA.
If the protected objects are FusionCompute VMs (non-OpenStack architecture):
- If storage array-based replication is used for DR, remote replication secondary LUNs of the recovery plan must be mapped to VMs at the DR site.
- If the networks of the production site and DR site are not isolated, you can configure different recovery IP addresses for test VMs and production VMs on the Protected Object tab page to avoid IP address conflicts and ensure service continuity at the production site.
- After adding or removing disks for a protected VM, refresh the information about the VM and manually enable DR for the protected group where the VM resides in time.
VMware VMs:
If the networks of the ESXi clusters or hosts at the production site and DR site are not isolated, you can configure different recovery IP addresses for test VMs and production VMs on the Protected Object tab page of the recovery plan to avoid IP address conflicts and ensure service continuity at the production site.
If application data is automatically replicated by storage instead of being periodically replicated based on the schedule specified upon the protected group creation, the data replication must be stopped before you start the DR test to prevent possible test failures. You can use either of the following methods to stop storage-based replication on the device management software:
- When the remote replication pair for the protected applications is in the synchronized state and the data is consistent, split the remote replication pair to temporarily stop data replication.
- Change the remote replication policy to manual synchronization for the protected applications.
If the information about storage devices, hosts, or VMs is modified at the production or DR site, manually refresh the information. For details, see Refreshing Resource Information.

Context

The data test in the DR center is used to check its data availability.

You are advised to configure application-based protection policies for Oracle, SQL Server, DB2, VMware vSphere VMs, FusionCompute VMs and SAP HANA streamlining the test procedure to a few clicks.

You are advised to configure LUN-based protection policies for other applications to enable automatic test configuration on the storage system. For this purpose, you need to manually or use self-defined scripts to start and test applications.

In the DR test, snapshots at the DR site can be mapped only to initiators.

Due to the importance of DR tests, notify the following:

Before testing a protected group whose protection type is database, ensure that all database connections at the DR site are disconnected.
During a DR test, system and service administrators are not allowed to perform any maintenance operation.
Test data must be cleared before the next DR test.
After a test is complete, test data must be cleared as soon as possible. If the environment is recovered after a network failure or eReplication environment shutdown during the test, it is possible that some data cannot be cleared. In this case, you must manually clear the test data, then perform clearing again.

Procedure

Log in to eReplication in the DR center.
Test a recovery plan.
1. On the menu bar, select Utilization > Data Restore.
2. Select the recovery plan to be tested, and click Test in the Operation area.
3. Perform the following steps based on the type of the recovery plan:
  
  If Huawei UltraPath has been installed on the Linux-based DR host, ensure that I/O suspension time is not 0 and all virtual devices generated by UltraPath have corresponding physical devices. For details, see the OceanStor UltraPath for Linux xxx User Guide.
- If the type of protected objects is Oracle, perform the following operations:
  1. Select DR Site.
  2. Select Available DR Hosts or Host Groups (This operation is optional when the protected object type is LUN).
    If the storage array used at the DR site is T series V2 or later, the to-be-recovered host selected by a user can belong to only one host group on the storage array, and the host group can belong to only one mapping view. Moreover, the storage LUN used by protected applications and its corresponding secondary remote replication LUNs must belong to one LUN group, and the LUN group must reside in the same mapping view as the host group. If the storage array version is T series V2R2, deselect Enable Inband Command to change the mapping view attribute after the mapping view is created.
    If the storage array is T series V2R2 or later, or 18000 series, automatic host adding and storage mapping are provided. Ensure that the storage is connected to hosts' initiators properly. In this manner, the system can automatically create hosts, host groups, LUN groups, and mapping views on the storage. The creation principles are as follows:
  1. Click Test.
  2. In the Warning dialog box that is displayed, read the content of the dialog box carefully and select In the Warning dialog box that is displayed, read the content of the dialog box carefully and select I have read and understood the consequences associated with performing this operation.
  3. Click OK.
- If the type of protected objects is VMware VM, perform the following steps:
  1. Select a recovery cluster.
    VMs will be recovered to the cluster. Select DR Site, DR vCenter, and DR Cluster.
    
    Upon the first network recovery, you need to set the cluster information.
  1. Select a recovery network.
    The network is used to access recovered VMs.
    If Production Resource and DR Resource are not paired, select Production Resource and DR Resource, and click Add to the mapping view to pair them.
    During a DR test, do not select Keep the mac unchange. Otherwise, the MAC addresses of the production VM and DR VM conflict and the IP addresses cannot be pinged.
  1. Set Logical Port IP Address to recover hosts in the cluster to access DR file systems over the logical port.
    
    In scenarios where the asynchronous replication (NAS) DR solution is deployed, you need to set Access Settings.
  1. Stop non-critical VMs when executing recovery.
    In the Available VMs list, select non-critical VMs to stop them to release computing resources.
  2. Click Fault Recovery.
After a test is complete, verify that applications are started in the remote DR center.
Verify that applications are started and accessed successfully. If an application fails to be started or cannot execute read and write operations, contact Huawei technical support.
- If the protection policies are based on applications, check whether the applications are started successfully and data can be read and written correctly.
- If the protection policies are based on LUNs, log in to the application host in the DR center, scan for disks, and start applications. Then check whether the applications are started successfully and data can be read and written correctly.
  
  You can use self-developed scripts to scan for disks, start applications, and test applications.
The test data generated at the DR site needs to be cleared and resources need to be restored to the status before the test to facilitate future DR or planned migration.
- In the Oracle application, the database is disabled but the cluster is enabled by default on the eReplication Agent. If you need to disable clusters, modify the configuration of disabling clusters. For details, see Changing the Configuration of Stopping the Oracle Cluster.
- If the protected groups are local file systems, ensure that programs and files on the file systems at the DR site have been closed before clearing is performed.
- If the information about storage devices, hosts, or VMs is modified at the production or DR site, manually refresh the information. For details, see Refreshing Resource Information.
1. Select the recovery plan whose data needs to be cleared, and click More > Clear on the Operation list.
2. Click OK.