Validating YARN Resource Manager Setup
After configuring the YARN Resource Manager, it's important to validate the setup to ensure that it is working correctly. Here are some steps you can take to validate the YARN Resource Manager setup:
Check YARN Resource Manager Status
You can check the status of the YARN Resource Manager using the yarn rmadmin
command:
yarn rmadmin -getServiceState
This command should return the current state of the YARN Resource Manager, such as ACTIVE
or STANDBY
(if running in high availability mode).
Verify YARN Resource Manager Web UI
You can access the YARN Resource Manager web UI by navigating to the configured address and port in a web browser. The web UI should display information about the cluster, including the available resources, running applications, and more.
Submit a Test Application
To verify that the YARN Resource Manager is functioning correctly, you can submit a test application to the cluster. You can use the yarn jar
command to submit a MapReduce job, for example:
yarn jar /path/to/hadoop-mapreduce-examples.jar wordcount /input/path /output/path
This will submit a WordCount MapReduce job to the YARN cluster, and you can monitor the job's progress and completion in the YARN Resource Manager web UI.
Check YARN Resource Manager Logs
You can also check the YARN Resource Manager logs for any errors or warnings that may indicate issues with the setup. The logs are typically located in the $HADOOP_LOG_DIR
directory.
tail -n 100 $HADOOP_LOG_DIR/yarn-*-resourcemanager-*.log
By following these steps, you can ensure that the YARN Resource Manager is properly configured and functioning as expected.