Creating an MRS Data Source Connection

Scenario

Before GaussDB(DWS) reads data from MRS HDFS, you need to create an MRS data source connection that functions as a channel of transporting data warehouse cluster data and MRS cluster data.

Impact on the System

• You can create only one MRS data source connection in the data warehouse cluster at a time.
• When an MRS data source connection is being created, the system automatically adds inbound and outbound rules to security groups of the data warehouse cluster and MRS cluster. Nodes in the same subnet can be accessed.
• For the MRS cluster with Kerberos authentication enabled, the system automatically adds a Machine-Machine user that belongs to user group supergroup to the MRS cluster.

Prerequisites

• You have created a data warehouse cluster and recorded the AZ, VPC, and subnet where the cluster resides.
• An MRS cluster of the analysis type has been created.

Procedure

1. Log in to the management console.
2. Choose Service List > Analytics > MapReduce Service to enter the MRS management console and create a cluster.

   Configure parameters as required. For details, see "Cluster Operation Guide > Custom Creation of a Cluster" in the MapReduce Service User Guide.

   • The AZ, VPC, and subnet of the MRS cluster must be the same as those of the data warehouse cluster.
   • Cluster Type must be Analysis Cluster.
   • Cluster Version supports MRS 1.9.2 (recommended).
     

     Cluster Version can also be set to 1.6.x, 1.7.x, 1.8.x, or 2.0.x.

   • In the Analysis Components area, select Hive, Tez, and Spark2x.
   

   If you enable Kerberos authentication for an MRS cluster, use MRS Manager to create a user for interconnecting GaussDB(DWS) with the system after the MRS cluster is created. The user type must be Human-Machine and the user, user group hadoop, and role Manager_administrator must be bound together. The user password must be changed on the MRS Manager page after the user is created.

   If you already have a qualified MRS cluster, skip this step.

3. Choose Service List > Analytics > GaussDB(DWS).
4. On the GaussDB(DWS) management console, click Clusters.
5. In the cluster list, click the name of a cluster. On the page that is displayed, click the MRS Data Sources tab.
6. Click Create MRS Cluster Connection and configure parameters.

   Table 1 MRS cluster connection parameters

   Parameter	Description
   MRS Data Source	Specifies the MRS cluster to which GaussDB(DWS) can connect. By default, all available analytic MRS clusters that are in the same VPC and subnet as the current data warehouse cluster and in the Available state are displayed. After you select an MRS cluster, the system automatically displays whether Kerberos authentication is enabled for the selected cluster. Click View MRS Cluster to view its detailed information. If the MRS Data Source drop-down list is empty, click Create MRS Cluster to create an MRS cluster.
   Description	Describes the connection.

7. Click OK to save the connection.

   Configuration Status turns to Creating. You can view the connection that is successfully created in the MRS data source list and the connection status is Available.

   

   • In the Operation column, you can click Update Configurations to update MRS Cluster Status and Configuration Status. During configuration update, you cannot create a connection. The system checks whether the security group rule is correct. If the rule is incorrect, the system rectifies the fault. For details, see Updating the MRS Data Source Configuration.
   • In the Operation column, you can click Delete to delete the unnecessary connection. When deleting a connection, you need to manually delete the security group rule.