An HDFS connection stores the information that Oracle GoldenGate uses to connect to a Hadoop Distributed File System (HDFS) cluster. After the connection is created and validated, you can reuse it when configuring Replicat processes that write transactional data to HDFS.

The connection stores the HDFS client configuration independently of the Replicat configuration, allowing multiple Replicat processes to reuse the same validated connection. The connection uses the HDFS client configuration provided in the Hadoop configuration file to establish communication with the HDFS cluster.

Before creating an HDFS connection, ensure that you have the following:

• An Oracle GoldenGate deployment.
• Network connectivity between the Oracle GoldenGate deployment and the HDFS cluster.
• The core-site.xml configuration file for the target Hadoop cluster.
• Required Hadoop client libraries installed if additional runtime dependencies are required.
• Common runtime settings, such as the runtime classpath, if additional client libraries are required.
• Proxy information if the Oracle GoldenGate deployment accesses the HDFS cluster through an HTTP proxy.

Use the Add Connection page to create an HDFS connection.

Procedure

1. In the navigation menu, select DB Connections.
2. Click Add Connection.
3. In Connection Alias, enter a unique name for the connection.
4. From Technology Type, select HDFS.
5. In the Technology Settings section, provide the HDFS connection information. Configure the following technology settings:
   Core Site XML – Upload the core-site.xml configuration file for the target HDFS cluster. Oracle GoldenGate for Distributed Applications and Analytics uses the configuration contained in this file to establish communication with the HDFS cluster. This field is required.

   Note:

   Ensure that the uploaded core-site.xml file matches the configuration of the target Hadoop cluster.
6. Configure Common Settings, if additional runtime configuration is required.

   Configure the following common settings:

   Classpath – Specifies the runtime classpath used to load the required Hadoop client libraries. You can use Dependency Downloader to download client libraries.

   Note:

   • Download the supported Hadoop client libraries by using the Dependency Downloader for HDFS.
   • Configure the runtime classpath to reference the downloaded client libraries before starting the Replicat process.
7. (Optional) Configure Proxy Settings if the Oracle GoldenGate for Distributed Applications and Analytics deployment accesses the HDFS cluster through an HTTP proxy.

   Configure the following proxy settings:

   • Proxy URL – Specifies the URL or host name of the proxy server used to access the HDFS cluster.
   • Proxy Port – Specifies the port number of the proxy server.
   • Proxy Username – Specifies the user name for proxy authentication, if required.
   • Proxy Password – Specifies the password for proxy authentication. This field is treated as sensitive information.
   • Truststore – Specifies the Java truststore file that contains the certificate authority (CA) certificates used to validate the proxy server certificate, when required.
   • Truststore Password – Specifies the password associated with the truststore.
   • Keystore – Specifies the Java keystore file containing the client certificate and private key used for client authentication, when required.
   • Keystore Password – Specifies the password associated with the keystore.
   • SSL Key Password – Specifies the password protecting the private key stored in the keystore when it differs from the keystore password.

   Note:

   Configure the proxy and SSL settings only if the Oracle GoldenGate for Distributed Applications and Analytics deployment accesses the HDFS cluster through a proxy that requires authentication or TLS. If the deployment has direct network connectivity to the HDFS cluster, leave the Proxy Settings blank.
8. Click Submit.
9. On the DB Connections page, click DBLOGIN to validate the connection.

   Note:

   A successful DBLOGIN validates only the saved connection information. It does not validate the Replicat configuration or HDFS Handler configuration. After successful validation, the connection is available for selection during Replicat creation.

After the HDFS connection has been successfully validated:

1. Create or edit a Replicat.
2. Select HDFS as the target technology.
3. Select the validated HDFS connection.
4. Complete the remaining Replicat configuration.
5. Create the Replicat.
6. Configure the remaining HDFS Handler properties before starting the Replicat.