Updating the MRS Data Source Configuration

Scenario

For MRS, if the following parameter configurations of the HDFS cluster change, data may fail to be imported to the data warehouse cluster from the HDFS cluster. Before importing data using the HDFS cluster, you must update the MRS data source configuration.

Parameter	Description
dfs.client.read.shortcircuit	Specifies whether to enable the local read function.
dfs.client.read.shortcircuit.skip.checksum	Specifies whether to skip data verification during the local read.
dfs.client.block.write.replace-datanode-on-failure.enable	Specifies whether to replace the location storing copies with the new node when data blocks fail to be written to HDFS.
dfs.encrypt.data.transfer	Specifies whether to enable data encryption. The value true indicates that the channels are encrypted. The channels are not encrypted by default. NOTE: This parameter is available only for clusters with Kerberos authentication enabled. This parameter is valid only when hadoop.rpc.protection is set to privacy.
dfs.encrypt.data.transfer.algorithm	Specifies the encryption and decryption algorithm for key transmission. This parameter is valid only when dfs.encrypt.data.transfer is set to true. The default value is 3des, indicating that the 3DES algorithm is used for encryption.
dfs.encrypt.data.transfer.cipher.suites	Specifies the encryption and decryption algorithm for the transmission of actually stored data. If this parameter is not specified, the cryptographic algorithm specified by dfs.encrypt.data.transfer.algorithm is used for data encryption. The default value is AES/CTR/NoPadding.
dfs.replication	Specifies the default number of data copies.
dfs.blocksiz	Specifies the default size of a data block.
hadoop.security.authentication	Specifies the security authentication mode.
hadoop.rpc.protection	Specifies the RPC communication protection mode. Default value: Security mode (Kerberos authentication enabled): privacy Common mode (Kerberos authentication disabled): authentication NOTE: authentication: indicates that only authentication is required. integrity: indicates that authentication and consistency check need to be performed. privacy: indicates that authentication, consistency check, and encryption need to be performed.
dfs.domain.socket.path	Specifies the locally used Domain socket path.

Prerequisites

You have created an MRS data source connection for the data warehouse cluster.

Impact on the System

When you are updating an MRS data source connection, the data warehouse cluster will automatically restart and cannot provide services.

Procedure

On the GaussDB(DWS) management console, choose Clusters > Dedicated Clusters.
In the cluster list, click the name of a cluster. On the page that is displayed, click MRS Data Sources.
In the MRS data source list, select the MRS data source that you want to update. In the Operation column, click Update Configurations.

MRS Cluster Status and Configuration Status of the current connection will be updated. 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.