YARN and Mapred commands

In this recipe, we will cover a few of the important commands which can help with the administration of YARN.

Until now, after making any change to the configuration, we have restarted the YARN daemons. But, this is not always required if the parameters already exist in the configuration files. Updating the queue list and capacity can be done dynamically at run time. In this recipe, we will cover a few of the easy ways to make changes.

Getting ready

For this recipe, you will again need a running cluster with at least HDFS and YARN configured and have the queue setup as discussed in this chapter. It is recommended that users go through all the previous recipes in this chapter before following this particular recipe.

How to do it...

1. Connect to the master1.cyrus.com master node and switch as user hadoop.

2. The first thing is to list the queues configured using the following command:

   $ mapred queue -list
   

3. The preceding command will list queues, along with their status as shown...