Making Preparations

This section describes how to migrate HDFS, HBase, and Hive data to an MRS cluster in different scenarios. During data migration, data may be overwritten, lost, or damaged. This document is for reference only. Please cooperate with Huawei Cloud technical personnel to formulate and implement a specific data migration solution.

Make preparations on a source cluster before data migration to prevent the source cluster from generating new data during data migration, thereby avoiding data inconsistency between the source and destination clusters after data migration. Before data migration is complete, the destination cluster must be in the initial state and cannot run any other services except data migration jobs.

Stopping Cluster Services and the Related Services

If the Kafka service is involved in your cluster, stop all jobs that generate data in Kafka. Wait until the Kafka consumption tasks have consumed the inventory data in Kafka, and then perform the next step.
Stop all services and jobs related to HDFS, HBase, and Hive, and stop the HBase and Hive services.

Establishing a Data Transmission Channel

If the source cluster and destination cluster are deployed in different VPCs in the same region, create a network connection between the two VPCs to establish a data transmission channel at the network layer. For details, see VPC Peering Connection Overview.
If the source cluster and destination cluster are deployed in the same VPC but belong to different security groups, add security group rules to each security group on the VPC management console. In the security rules, Protocol is set to ANY, Transfer Direction is set to Inbound, and Source is set to Security Group (the security group of the peer cluster).
- To add an inbound rule to the security group of the source cluster, select the security group of the destination cluster in Source.
- To add an inbound rule to the security group of the destination cluster, select the security group of the source cluster in Source.
If the source and destination clusters are deployed in the same security group of the same VPC and Kerberos authentication is enabled for both clusters, you need to configure mutual trust between the two clusters.