Use OSS-HDFS as the underlying storage of HBase - Object Storage Service

HBase is a real-time database that provides high write performance in the Hadoop ecosystem. OSS-HDFS is a storage service released by Alibaba Cloud and is compatible with the HDFS API. JindoSDK allows HBase to use OSS-HDFS as the underlying storage and supports the storage of write-ahead logging (WAL) files. This way, computing and storage resources are separated. OSS-HDFS is more flexible than the local HDFS storage and reduces O&M costs.

Prerequisites

For example, to use Elastic Compute Service (ECS) as your deployment environment, you will need to create an instance
A Hadoop environment is created. For more information about how to install Hadoop, see Step 2: Set up a Hadoop runtime environment.
Apache HBase is deployed. For more information, see Apache HBase.
OSS-HDFS is enabled for a bucket and permissions are granted to access OSS-HDFS. For more information, see Enable OSS-HDFS and grant access permissions.

Procedure

Connect to the ECS instance. For more information, see Connect to an ECS instance.
Configure JindoSDK.
1. Download the latest version of the JindoSDK JAR package. To download JindoSDK, visit GitHub.
2. Decompress the downloaded installation package.
  
  The following sample code provides an example on how to decompress a package named jindosdk-x.x.x-linux.tar.gz. If you use another version of JindoSDK, replace the package name with the name of the corresponding JAR package.
```
tar -zxvf jindosdk-x.x.x-linux.tar.gz -C /usr/lib
```
  Note
  x.x.x indicates the version number of the JindoSDK JAR package.
3. Configure JINDOSDK_HOME.
```
export JINDOSDK_HOME=/usr/lib/jindosdk-x.x.x-linux
export PATH=$JINDOSDK_HOME/bin:$PATH
```
4. Configure HADOOP_CLASSPATH.
```
export HADOOP_CLASSPATH=$HADOOP_CLASSPATH:${JINDOSDK_HOME}/lib/*
```
  Important
  Specify the installation directory of the package and configure environment variables on all required nodes.
5. Install the downloaded JindoSDK JAR package to the path specified by classpath.
```
cp jindosdk-x.x.x-linux/lib/jindo-core-x.x.x.jar <HADOOP_HOME>/share/hadoop/hdfs/lib/
cp jindosdk-x.x.x-linux/lib/jindo-sdk-x.x.x.jar <HADOOP_HOME>/share/hadoop/hdfs/lib/
```

Configure the implementation class of OSS-HDFS and specify the AccessKey pair that you want to use to access the bucket.

Configure the implementation class of OSS-HDFS in the core-site.xml file of HBase.

<configuration>
    <property>
        <name>fs.AbstractFileSystem.oss.impl</name>
        <value>com.aliyun.jindodata.oss.JindoOSS</value>
    </property>

    <property>
        <name>fs.oss.impl</name>
        <value>com.aliyun.jindodata.oss.JindoOssFileSystem</value>
    </property>
</configuration>

In the core-site.xml file of HBase, specify the AccessKey ID and AccessKey secret that you want to use to access the bucket for which OSS-HDFS is enabled.

<configuration>
    <property>
        <name>fs.oss.accessKeyId</name>
        <value>LTAI********</value>
    </property>

    <property>
        <name>fs.oss.accessKeySecret</name>
        <value>KZo1********</value>
    </property>
</configuration>

Configure the endpoint of OSS-HDFS.

You must specify the endpoint of OSS-HDFS if you want to use OSS-HDFS to access buckets in Object Storage Service (OSS). We recommend that you configure the path that is used to access OSS-HDFS in the oss://{yourBucketName}.{yourBucketEndpoint}/{path} format (example: oss://examplebucket.cn-shanghai.oss-dls.aliyuncs.com/exampleobject.txt). After you configure the access path, JindoSDK calls the corresponding OSS-HDFS operation based on the specified endpoint in the access path.

You can also configure the endpoint of OSS-HDFS by using other methods. The endpoints that are configured by using different methods have different priorities. For more information, see Quick start: Connect a non-EMR cluster to the OSS-HDFS service.
Specify a storage path for HBase.

To specify a path in OSS as the storage path for data and WAL files in HBase, you must change the value of the hbase.rootdir parameter in the hbase-site configuration file to the OSS path. The path is in the oss://bucket.endpoint/hbase-root-dir format.

Important
To release clusters, you must disable tables and make sure that all update operations performed on WAL files are synchronized to the HFiles.