Using the Configuration Wizard

Prerequisites

• The configuration wizard is available only for the default cluster. The default cluster provides the following functions: cluster topology maintenance, global configuration information synchronization, and LS/POE information maintenance.
• Before configuring the wizard for the first time, log in to DeviceManager of the default cluster, choose Settings > Object Service Settings > Global Namespace, and click Add Object Cluster to add a non-default cluster.

Procedure

1. Choose Data Protection > Configuration > Cross-Site DR.
2. Click Configuration Wizard.

   The cross-site DR configuration wizard page is displayed.

3. Configuring a default cluster.
   1. Select a default cluster.
      

      You need to select a default cluster only when Enable Support for Cross-Site DR is not turned on for any replication cluster in the system. If Enable Support for Cross-Site DR is turned on for a replication cluster, the replication cluster is the default cluster.

      1. In the Default Cluster area, click Choose.

         The Add Default Replication Cluster page is displayed on the right.

      2. Select a replication cluster.
         

         If no replication cluster is available, click Create to create one. For details, see Creating a Replication Cluster.

      3. Click OK.
         The Enable Support for Cross-Site DR page is displayed.

         

         After cross-site DR is enabled:

         1. The DNS TTL will change from 120s to 5s. If the system fails to change the TTL, run the following CLI command to change it.

            change dns ttl dns_ttl=5

         2. Data write will be disabled at the passive site. If the system fails to disable data write at the passive site, run the following CLI command to disable it.

            change passive writeswitch oscPassiveWriteSwitch=false

         3. Automatic takeover will be disabled, so that after the faulty cluster is recovered, it does not automatically take over services. Otherwise, data written before the failback may fail to be read after the failback. If the system fails to disable automatic takeover, run the following CLI command to disable it.

            change cluster_status auto_switch value=off

      4. Click OK.
   2. Add a remote device.
      1. In the Remote Device area, click Add.

         The Add Remote Device page is displayed on the right.

      2. Set parameters for the remote device. Table 1 describes related parameters.

         Table 1 Remote device parameters

         Parameter	Description
         Local Device Replication IP Address	Select a replication network IP address of a local device. NOTE: You can select any replication network IP address of the local device. After the initial connection is complete, the system automatically connects all replication links between the local and remote devices.
         Remote Device Replication IP Address	Replication network IP address of a remote device. NOTE: If there are multiple devices in the remote replication cluster, you can use any of them.
         Pre-Shared Key Label	Label for identifying the pre-shared key of a cluster. NOTE: Enter the pre-shared key label of a remote replication cluster.
         Pre-Shared Key	Implement identity authentication. This parameter functions together with Pre-Shared Key Label. NOTE: Enter the pre-shared key of a remote replication cluster.

      3. Click OK.
         

         • Click Add again to add another remote device.
         • When configuring cross-site DR for three or more sites, add interconnected remote devices to the remote clusters to ensure interconnection between sites.

           For example, to configure cross-site DR for three clusters, after adding clusters B and C to cluster A, continue adding remote cluster C to cluster B so that clusters A, B, and C are interconnected with each other.

         • To remove remote devices, select desired remote devices and click Remove. You can also click More on the right of a desired remote device and choose Remove to remove the device.
   3. Click Next.

4. Configure a replication group.
   

   If you do not want to create a replication group, click Next to skip this step. After completing the configuration wizard, you can create or manage replication groups, and modify the DNS scheduling sequence and associated namespaces of replication groups on the Replication Group tab page.

   1. In the Replication Group area, click Create.

      The Create Replication Group page is displayed on the right.

   2. Set a name for the replication group.
      

      • The name can contain 1 to 255 characters.
      • The name can consist of only letters, digits, hyphens (-), and underscores (_), and must start with a letter and cannot end with a hyphen (-) or underscore (_).
   3. Select a policy type for the replication group.
      • Replica: Complete data is replicated to all clusters.

        For example, if a replication group has three clusters, data of all buckets in the replication group is stored at these clusters.

      • EC: Data is divided into multiple data blocks and stored at the data fragment clusters. If you select this option, you need to specify the number of parity fragments. The number of parity fragments is the number of nodes that can be faulty in a replication group. If a cluster is faulty, data of the faulty cluster can be calculated by reading data of other clusters. EC reduces storage space occupation and saves costs.

        For example, three clusters are selected, including two data fragment clusters for storing data and one parity fragment cluster for storing parity data. If a cluster that stores data is faulty, the data of the faulty cluster can be calculated based on the data of the parity cluster and the data of the other data cluster.

   4. In the Available Replication Clusters list, select replication clusters. In the Selected Replication Clusters list, set Cluster Type and Replication Mode of the clusters. If only one active cluster is selected, you can specify a passive cluster among all selected passive clusters to automatically take over services in case of a fault of the active cluster. Select the synchronous or asynchronous replication mode for the clusters. The sequence of selecting replication clusters is used as the DNS scheduling sequence by default. The first healthy active cluster in the sequence receives services. In the Selected Replication Clusters list, you can click the up or down arrow to adjust the sequence of replication clusters to adjust the DNS scheduling sequence of the replication group.
      

      • If you select Replica for the policy type, select at least two clusters (containing at least one active cluster).
      • If you select EC for the policy type, select at least (2 + the number of parity fragments) clusters (containing at least one active cluster).
      • By default, the passive cluster (auto takeover) is in the read-only state, and the namespace associated with the replication group of the passive cluster (auto takeover) is also in the read-only state. If the active cluster is faulty, the cluster (auto takeover) automatically switches from the read-only state to the read/write state, so do the associated namespace.
      • For the same cluster type, replication type, and DNS scheduling sequence, only one replication group can be created, while for the same cluster type and replication type, and different DNS scheduling sequences, different replication groups can be created.
      • Synchronous replication is used between two synchronous replication clusters, and asynchronous replication is used between other clusters. If a replication group contains synchronous replication clusters, the number of synchronous replication clusters can only be 2 or 3, and the number of synchronous and asynchronous replication clusters must be less than or equal to 12.
      • If the policy type of a replication group is EC, clusters in the replication group do not support the synchronous replication mode.
   5. Click OK.
      

      • Click Create again to create another replication group.
      • Click More on the right of a desired replication group and choose Modify DNS Scheduling Sequence. On the page that is displayed, select the cluster whose sequence needs to be adjusted and click Up, Down, Move to Top, or Move to Bottom to adjust the DNS scheduling sequence. You can also perform the operation by referring to Changing the DNS Scheduling Sequence after completing the configuration wizard.
      • Click More on the right of a desired replication group and choose Modify. On the page that is displayed, modify Cluster Type, Replication Mode, or Auto Takeover of passive clusters. You can also perform the operation by referring to Modifying a Replication Group after completing the configuration wizard.
      • To delete replication groups, select desired replication groups and click Delete. You can also click More on the right of a desired replication group and select Delete to delete the replication group. You can also perform the operation by referring to Deleting a Replication Group after completing the configuration wizard.
   6. Click Next.

5. Associate a namespace with the replication group.
   

   • If no replication group is configured in the previous step, no namespace can be associated. If you do not want to associate a namespace for now, click Finish to skip this step. After completing the configuration wizard, you can associate a namespace on the Replication Group tab page. For details, see Associating a Namespace with a Replication Group.
   • If the object service uses IAM authentication, you cannot perform namespace association operations on DeviceManager. If necessary, create a replication bucket by referring to Object Service API Reference > Operations on Buckets" > Creating a Bucket in the Service Plane API Description for Object of the corresponding version.
   1. In the Associate Namespace area, select a desired replication group and click Create.

      The Create Namespace page is displayed.

   2. For details about how to create a namespace, see Associating a Namespace with a Replication Group.
      

      • Click More on the right of a desired namespace and select Start Replication or Pause Replication to enable or disable replication for the namespace. You can also perform the operation by referring to Managing Associated Namespaces after completing the configuration wizard.
      • Click More on the right of a desired namespace and select Modify. On the page that is displayed, modify the EC threshold and retention period. The modification operation is supported only when the policy type of the replication group is set to EC. You can also perform the operation by referring to Managing Associated Namespaces after completing the configuration wizard.
      • To delete namespaces, select desired namespaces and click Delete. You can also click More on the right of a desired namespace and select Delete.
   3. Click Finish.