Verifying the Consistency of Data Migrated Between MRS HBase Clusters

This section describes how to use MgC to verify the consistency of data migrated between different versions of Huawei Cloud MRS HBase clusters.

Preparations

Install the MgC Agent, an MgC tool used for data verification, in the source intranet environment and register an account for using the MgC Agent. For details, see Installing the MgC Agent for Linux.
Add the mappings between the hostnames and IP addresses of all nodes in the source and target clusters to the /etc/hosts file on the server where the MgC Agent is installed.
1. On the server where the MgC Agent is installed, open the /etc/hosts file.
2. In the /etc/hosts file, add a line for each node in the source and target clusters in the following format:
```
IP address Hostname
```
  For example, if a node uses the IP address 192.168.1.1 and has the hostname source-node-01, add the following information:
```
192.168.1.1 source-node-01
```
3. After all mappings are added, save and close the /etc/hosts file.
4. Ping a hostname to check whether it can be resolved successfully. For example:
```
ping source-node-01
```

Procedure

Sign in to the MgC console.
In the navigation pane on the left, choose Settings.
Under Migration Projects, click Create Project.

Figure 1 Creating a project
Set Project Type to Complex migration (for big data), enter a project name, and click Create.

Figure 2 Creating a big data migration project
Connect the MgC Agent to MgC. For more information, see Connecting the MgC Agent to MgC.
After the connection is successful, add the username/key pairs for accessing the source and target MRS HBase clusters to the MgC Agent. For more information, see Adding Resource Credentials. Enter the username for logging in to the HBase client in the Username box and upload the configuration files for Key:
- For an unsecured cluster (with Kerberos authentication disabled), you need to upload five configuration files: core-site.xml, hdfs-site.xml, yarn-site.xml, mapred-site.xml, and hbase-site.xml. For details about how to obtain the configuration files, see Preparing the Configuration Files of the Running Environment. Review whether Kerberos authentication is enabled for the cluster in the basic cluster information.
- For a secured cluster (with Kerberos authentication enabled), upload seven files: core-site.xml, hdfs-site.xml, yarn-site.xml, krb5.conf, user.keytab, mapred-site.xml, and hbase-site.xml. The krb5.conf and user.keytab files contain the credentials of the cluster users. You can perform the following steps to obtain the two files. For details about how to obtain the other five configuration files, see Preparing the Configuration Files of the Running Environment.
  1. Log in to FusionInsight Manager, and choose System > Permission > User.
  2. Select developuser and choose More > Download Authentication Credential to download the authentication credential files.
  3. Decompress the downloaded file to obtain the user.keytab and krb5.conf files.
In the navigation pane, choose Migrate > Big Data Verification. In the navigation pane, under Project, select the project created in step 4.
If you are performing a big data verification with MgC for the first time, select your MgC Agent to enable this feature. Click Select MgC Agent. In the displayed dialog box, select the MgC Agent you connected to MgC from the drop-down list.

Ensure that the selected MgC Agent is always Online and Enabled before your verification is complete.
In the Features area, click Preparations.
Choose Connection Management and click Create Connection.

Figure 3 Creating a connection
On the Select Connection Type page, select HBase and click Next.

Set connection parameters based on Table 1 and click Test. If the test is successful, the connection is set up.

**Table 1** Parameters for creating an HBase connection
Parameter	Configuration
Connection To	Select Source.
Connection Name	The default name is HBase-4 random characters (including letters and numbers). You can also customize a name.
MgC Agent	Select the MgC Agent connected to MgC in step 5.
HBase Credential	Select the credential you added to the MgC Agent for accessing the source MRS HBase cluster in step 6.
Secured Cluster	Choose whether the cluster is secured.
ZooKeeper IP Address	Enter the IP address for connecting to the ZooKeeper node. You can enter the public or private IP address of the ZooKeeper node.
ZooKeeper Port	Enter the port for connecting to the ZooKeeper node.
HBase Version	Select the HBase version.
Collect Usage Metrics	This parameter is optional. If this option is enabled, usage metrics for your big data resources will be collected during the execution of tasks created using this connection. The collected information is used to generate reports on the MgC console and for performance optimization. NOTICE: Before using this function, ensure that the Huawei Cloud account you added to the MgC Agent has the read-only permission for MRS and DLI. If the selected credential is the one you currently use to access MgC, you can select This is my MgC credential, and the projects in the region you choose will be listed. Under Region, select the region where the data to be verified is located. Under Project, select the project where the data to be verified is stored. Under Cluster ID, enter the ID of the cluster where the data to be verified is located. If the selected Doris credential is not the one you currently use to access MgC: Under Region ID, enter the ID of the region where the data to be verified is located. For example, if the region is CN South-Guangzhou, enter cn-south-1. Under Project ID, enter the project ID corresponding to the region. Under Cluster ID, enter the ID of the cluster where the data to be verified is located. NOTE: To view the region ID and project ID, choose My Credentials > API Credentials. For details about how to obtain the cluster ID, see Obtaining an MRS Cluster ID.

After the connection test is successful, click Confirm. The cloud service connection is set up.
Choose Metadata Management and click Create Metadata Collection Task.

Figure 4 Create Metadata Collection Task

Configure the parameters for creating a metadata collection task and click Confirm.

**Table 2** Parameters for configuring a metadata collection task
Parameter	Configuration
Task Name	The default name is Metadata-Collection-4 random characters (including letters and numbers). You can also specify a name.
Metadata Connection	Select the connection created in step 12.
Databases (Optional)	Enter the names of the databases whose metadata needs to be collected. Use commas (,) to separate the database names. If no database name is specified, the metadata of all databases is collected.
Concurrent Threads	Set the maximum number of threads for executing the collection. The default value is 3. The value ranges from 1 to 10. Configuring more concurrent threads means more efficient collection, but more connection and MgC Agent resources will be consumed.

Under Tasks, you can review the created metadata collection task and its settings. You can modify the task by choosing More > Modify in the Operation column.

Figure 5 Managing a metadata collection task
Click Execute Task in the Operation column to run the task. Each time the task is executed, a task execution is generated.
Click View Executions in the Operation column. Under Task Executions, you can view the execution records of the task and the status and collection result of each task execution. When a task execution enters a Completed status and the collection results are displayed, you can view the list of databases and tables extracted from collected metadata on the Tables tab.

Figure 6 Managing task executions
In the Features area, click Table Management.

Under Table Groups, click Create. Configure the parameters for creating a table group and click Confirm.

**Table 3** Parameters for creating a table group
Parameter	Description
Table Group	Enter a name.
Metadata Connection	Select the connection created in step 12. CAUTION: A table group can only contain tables coming from the same metadata source.
Verification Rule	Select a rule that defines the method for verifying data consistency and the inconsistency tolerance. You can View More to see the details about the verification rules provided by MgC.
Description (Optional)	Enter a description to identify the table group.

On the Table Management page, click the Tables tab, select the data tables to be added to the same table group, and choose Option > Add Tables to Group above the list. In the displayed dialog box, select the desired table group and click Confirm.

You can manually import information of incremental data tables to MgC. For details, see Creating a Table Group and Adding Tables to the Group.
In the Features area, click Preparations.
Choose Connection Management and click Create Connection.

Figure 7 Creating a connection
On the Select Connection Type page, select HBase and click Next.

Set connection parameters based on Table 4 and click Test. If the test is successful, the connection is set up.

**Table 4** Parameters for creating an HBase connection
Parameter	Configuration
Connection To	Select Target.
Connection Name	The default name is HBase-4 random characters (including letters and numbers). You can also customize a name.
MgC Agent	Select the MgC Agent connected to MgC in step 5.
HBase Credential	Select the credential you added to the MgC Agent for accessing the target MRS HBase cluster in step 6.
Secured Cluster	Choose whether the cluster is secured.
ZooKeeper IP Address	Enter the IP address for connecting to the ZooKeeper node. You can enter the public or private IP address of the ZooKeeper node.
ZooKeeper Port	Enter the port for connecting to the ZooKeeper node. The default value is 2181.
HBase Version	Select the HBase version.
Collect Usage Metrics	This parameter is optional. If this option is enabled, usage metrics for your big data resources will be collected during the execution of tasks created using this connection. The collected information is used to generate reports on the MgC console and for performance optimization. NOTICE: Before using this function, ensure that the Huawei Cloud account you added to the MgC Agent has the read-only permission for MRS and DLI. If the selected credential is the one you currently use to access MgC, you can select This is my MgC credential, and the projects in the region you choose will be listed. Under Region, select the region where the data to be verified is located. Under Project, select the project where the data to be verified is stored. Under Cluster ID, enter the ID of the cluster where the data to be verified is located. If the selected Doris credential is not the one you currently use to access MgC: Under Region ID, enter the ID of the region where the data to be verified is located. For example, if the region is CN South-Guangzhou, enter cn-south-1. Under Project ID, enter the project ID corresponding to the region. Under Cluster ID, enter the ID of the cluster where the data to be verified is located. NOTE: To view the region ID and project ID, choose My Credentials > API Credentials. For details about how to obtain the cluster ID, see Obtaining an MRS Cluster ID.

On the MgC console, create a verification task for the source and target HBase clusters, respectively, and execute the tasks. For details, see Creating and Executing Verification Tasks. During the task creation, select the table group created in step 20.
- On the Select Task Type page, choose HBase.
- Select a verification method. For details about each verification method, see Verification Methods.
Wait until the task executions enter a Completed status. You can view and export the task execution results on the Verification Results page. For details, see Viewing and Exporting Verification Results.