OBS

This guide describes how to configure Alluxio with Open Telecom OBS as the under storage system. Object Storage Service (OBS) is a massive, secure and highly reliable cloud storage service provided by Huawei Cloud.

Prerequisites

To run an Alluxio cluster on a set of machines, you must deploy Alluxio binaries to each of these machines. You can either compile the binaries from Alluxio source code, or download the precompiled binaries directly.

OBS under storage is implemented as an under storage extension. Clone the alluxio-extensions repo and run the following command under <alluxio_extensions_home>/underfs/obs:

$ mvn package -DskipTests

The built jar can be found under the <alluxio_extensions_home>/underfs/obs/target.

Execute the following command on master to install the extension to all masters and workers defined in conf/masters and conf/workers:

$ ./bin/alluxio extensions install /PATH/TO/OBS/jar

See here for more details on Alluxio extension management.

In preparation for using OBS with Alluxio, follow the OBS quick start guide to create a OBS bucket.

Basic setup

To configure Alluxio to use OBS as its under storage system, you will need to modify the configuration file conf/alluxio-site.properties. If the file does not exist, create the configuration file from the template.

$ cp conf/alluxio-site.properties.template conf/alluxio-site.properties

Edit conf/alluxio-site.properties file to set the under storage address to an existing OBS bucket and folder you want to mount to Alluxio. For example, the under storage address can be obs://alluxio-obs-bucket/ to mount the whole bucket to Alluxio or obs://alluxio-obs-bucket/alluxio/data if only the folder /alluxio/data inside the bucket obs://alluxio-obs-bucket is mapped to Alluxio.

alluxio.master.mount.table.root.ufs=obs://<OBS_BUCKET>/<OBS_DIRECTORY>/

Specify the Huawei Cloud credentials for OBS access. In conf/alluxio-site.properties, add:

fs.obs.accessKey=<OBS_ACCESS_KEY>
fs.obs.secretKey=<OBS_SECRET_KEY>
fs.oss.endpoint=<OBS_ENDPOINT>

fs.obs.accessKey and fs.obs.secretKey is access keys for Huawei cloud, please follow the Access keys Guide to create and manage your keys.

fs.obs.endpoint specifies the endpoint of the bucket. Valid values are similar to obs.cn-east-2.myhuaweicloud.com and obs.cn-south-1.myhuaweicloud.com. Available endpoints are listed in the Region and Endpoint list under the Object Storage Service category.

Excample: Running Alluxio Locally with OBS

Start the Alluxio servers:

$ ./bin/alluxio format
$ ./bin/alluxio-start.sh local

This should start an Alluxio master and an Alluxio worker. You can see the master UI at http://localhost:19999.

Run a simple example program:

$ ./bin/alluxio runTests

Visit your OBS folder obs://<OBS_BUCKET>/<OBS_DIRECTORY> to verify the files and directories created by Alluxio exist.

To stop Alluxio, you can run:

$ ./bin/alluxio-stop.sh local

Advanced Setup

Nested Mount

An OBS location can be mounted at a nested directory in the Alluxio namespace to have unified access to multiple under storage systems. Alluxio’s Mount Command can be used for this purpose.

For example, the following command mounts a folder inside an OBS bucket into Alluxio directory /obs:

$ ./bin/alluxio fs mount --option fs.obs.accessKey=<OBS_ACCESS_KEY> \
  --option fs.obs.secretKey=<OBS_SECRET_KEY> \
  --option fs.obs.endpoint=<OBS_ENDPOINT> \
  /obs obs://<OBS_BUCKET>/<OBS_DIRECTORY>/