Starting and stopping queues

Queues in YARN can be in two states: RUNNING or STOPPED. A RUNNING state indicates that a queue can accept application submissions, and a STOPPED queue does not accept application submissions. The default state of any configured queue is RUNNING.

In Capacity Scheduler, parent queues and leaf queues can be stopped. For an application to be accepted at any leaf queue, all the queues in the hierarchy all the way up to the root queue must be running. This means that if a parent queue is stopped, all of the descendant queues in that hierarchy are inactive, even if their own state is RUNNING.

To stop a queue:

  1. In Cloudera Manager, select Clusters > YARN Queue Manager UI service. A graphical queue hierarchy is displayed in the Overview tab.
  2. Click on the three vertical dots on the queue and select Stop Queue .
  3. You will be prompted for a confirmation. Click OK to stop the queue.

To start a queue:

  1. In Cloudera Manager, select Clusters > YARN Queue Manager UI service. A graphical queue hierarchy is displayed in the Overview tab.
  2. Click on the three vertical dots on the queue and select Start Queue .
  3. You will be prompted for a confirmation. Click OK to start the queue.

Administrators can use the ability to stop and drain applications in a queue for a number of reasons, such as when decommissioning a queue and migrating its users to other queues. Administrators can stop queues at run-time, so that while current applications run to completion, no new applications are accepted. Existing applications can continue until they finish running, and thus the queue can be drained gracefully without any end-user impact.