Background

Alluxio provides a unified namespace mechanism that allows other file systems to be mounted to the file system of Alluxio. In addition, it allows upper-layer applications to use the unified namespace to access data scattered across different systems.

Operations

bin/alluxio fs mount <alluxio-path> <source-path>

Example 1. Mounting a COS bucket to an Alluxio directory

bin/alluxio fs mount --option fs.cos.access.key=<COS_SECRET_ID> \
    --option fs.cos.secret.key=<COS_SECRET_KEY> \
    --option fs.cos.region=<COS_REGION> \
    --option fs.cos.app.id=<COS_APP_ID> \
    /cos cos://<COS_BUCKET>/

Note：

AppID is optional.

Configure the COS configuration information in --options.

This command mounts the COS directory (specified by cos://bucket/xxx) to the /cos directory in Alluxio.

Example 2. Mounting an HDFS directory to an Alluxio directory

bin/alluxio fs mount /hdfs hdfs://data

This command mounts the /data directory of HDFS to the /hdfs subdirectory of Alluxio.

After the mount is successful, the mounted content can be viewed by running the alluxio fs ls command.

Example 3. Mounting an CHDFS directory to an Alluxio directory

Note：

This operation is only available to Alluxio version 2.3.0 or later in EMR2.5.0.

alluxio fs mount   \ 
 --option alluxio.underfs.hdfs.configuration=/usr/local/service/hadoop/etc/hadoop/core-site.xml  \
/chdfs ofs://f4modr7kmvw-wMqw.chdfs.ap-chongqing.myqcloud.com