Enabling service level authorization

In this recipe, we will look at service level authorization, which is a mechanism to ensure that the clients connecting to Hadoop services have the right permissions and authorization to access them. This is more of a global control in comparison to the control at the job queue level. Which users can submit jobs to the cluster or which Datanodes can connect to the Namenode based on the Datanode service user.

Service level authorization checks are performed much before any other checks, such as file permissions or permissions on sub queues.

Getting ready

For this recipe, you will need a running cluster with HDFS and YARN configured, and it is good to have a basic understanding of Linux users and permissions.

How to do it...

1. Connect to the nn1.cluster1.com master node and switch to user hadoop.
2. All the configuration goes into the hadoop-policy.xml file on each node in the cluster.
3. Firstly, allow all users to connect as DFSclient using the following configuration...