Configuring an Underlying Storage System

If you want to use a unified client API and a global namespace to access persistent storage systems including HDFS and OBS to separate computing from storage, you can configure the underlying storage system of Alluxio on MRS Manager. After a cluster is created, the default underlying storage address is hdfs://hacluster/, that is, the HDFS root directory is mapped to Alluxio.

Prerequisites

Alluxio has been installed in a cluster.
The password of user admin has been obtained. The password of user admin is specified by the user during MRS cluster creation.

Configuring HDFS as the Underlying File System of Alluxio

Security clusters with Kerberos authentication enabled do not support this function.

Go to the All Configurations page of Alluxio. See Modifying Cluster Service Configuration Parameters.
In the left pane, choose Alluxio > Under Stores, and modify the value of alluxio.master.mount.table.root.ufs to hdfs://hacluster/XXX/.

For example, if you want to use HDFS root directory/alluxio/ as the root directory of Alluxio, modify the value of alluxio.master.mount.table.root.ufs to hdfs://hacluster/alluxio/.
Click Save Configuration. In the displayed dialog box, select Restart the affected services or instances.
Click OK to restart Alluxio.

Configuring Huawei OBS as the Underlying File System of Alluxio

Method 1:

Configure an agency with the OBS OperateAccess permission for the cluster. For details, see Configuring a Storage-Compute Decoupled Cluster (Agency).
Go to the All Configurations page of Alluxio. See Modifying Cluster Service Configuration Parameters.
In the left pane, choose Alluxio > Under Stores, and modify the value of alluxio.master.mount.table.root.ufs to obs://<OBS_BUCKET>/<OBS_DIRECTORY>/. OBS_BUCKET is an existing OBS file system name, and OBS_DIRECTORY is a directory in the file system.
Click Save Configuration. In the displayed dialog box, select Restart the affected services or instances.
Click OK to restart Alluxio.

Method 2:

Configure an agency with the OBS OperateAccess permission for the cluster. For details, see Configuring a Storage-Compute Decoupled Cluster (Agency).
Log in to the active Master node. For details about how to determine the active and standby management nodes, see Determining Active or Standby Management Nodes of MRS Manager.
Run the following command to configure environment variables:

source /opt/client/bigdata_env

In the preceding command, /opt/client is the directory where current cluster client is installed. Change it based on the site requirements.
Run the following command to mount the internal directory of an OBS container to the /obs directory of Alluxio:

alluxio fs mount /obs obs://<OBS_BUCKET>/<OBS_DIRECTORY>/