This is the documentation for Cloudera Manager 4.8.4.
Documentation for other versions is available at Cloudera Documentation.

Starting, Stopping, and Restarting Services

Starting and Stopping All Services

It's important to start and stop services that have dependencies in the correct order. For example, because MapReduce has a dependency on HDFS, you must start HDFS before starting MapReduce. The Cloudera Management Services and Hue are the only two services that do not have a dependency on other services; although you can start and stop them at anytime, their preferred order is shown in the following procedures.

Starting All Services on All Hosts

To start all services on all hosts:

  1. Choose All Services from the Services tab.
  2. From the cluster-level Actions menu, choose Start. Click Start that appears in the next screen to confirm. When you see a Finished status, the service has started.
      Note: The cluster-level Start command starts only the CDH and other product services (Impala, Cloudera Search). It does not start the Cloudera Management Services. You must start the Management Service separately if it is not already running.

To start selected services:

  1. Choose All Services from the Services tab.
  2. Choose Start on the Actions menu for the service you want to start. Click Start that appears in the next screen to confirm. When you see a Finished status, the service has started.
  3. Repeat Step 2 for each service you want to start.

The order in which to start the services is:

  1. HDFS
  2. MapReduce
  3. YARN
  4. ZooKeeper
  5. HBase
  6. Hue
  7. Oozie
  8. Impala
  9. Flume
  10. Cloudera Management Services
  Note:

If you are unable to start the HDFS service, it's possible that one of the roles instances, such as a DataNode, was running on a host that is no longer connected to the Cloudera Manager Server host, perhaps because of a hardware or network failure. If this is the case, the Cloudera Manager Server will be unable to connect to the Cloudera Manager Agent on that disconnected host to start the role instance, which will prevent the HDFS service from starting. To work around this, you can stop all services, abort the pending command to start the role instance on the disconnected host, and then restart all services again without that role instance. For information about aborting a pending command, see Aborting a Pending Command.

Stopping All Services on All Hosts

To stop all services on all hosts:

  1. Choose All Services from the Services tab.
  2. From the cluster-level Actions menu, choose Stop. Click Stop that appears in the next screen to confirm. When you see a Finished status, the service has stopped.
      Note: The cluster-level Stop command does not stop the Cloudera Management Services. You must stop that service separately.

To stop selected services:

  1. Choose All Services from the Services tab.
  2. Choose Stop on the Actions menu for the service you want to stop. Click Stop that appears in the next screen to confirm. When you see a Finished status, the service has stopped.
  3. Repeat Step 2 for each service you want to stop.

The order in which to stop the services is:

  1. Cloudera Management Services
  2. Flume
  3. Impala
  4. Oozie
  5. Hue
  6. HBase
  7. ZooKeeper
  8. YARN
  9. MapReduce
  10. HDFS

Restarting a Service

It is sometimes necessary to restart a service, which is essentially a combination of stopping a service and then starting it again. For example, if you change the hostname or port where the Cloudera Manager is running, or you enable TLS security, you must restart the Cloudera Management Services to update the URL to the Server.

  Note: If you need to restart all services, you should stop them all first and then start them all again in the order described above. It is not possible to restart all of the services in the correct order using the Restart command.

To restart a service:

  1. Choose All Services from the Services tab.
  2. Choose Restart on the Actions menu for the service you want to restart. Click Restart that appears in the next screen to confirm. When you see a Finished status, the service has restarted.