This is the documentation for Cloudera 5.3.x.
Documentation for other versions is available at Cloudera Documentation.

Maintenance Mode

Required Role:

Maintenance mode allows you to suppress alerts for a host, service, role, or an entire cluster. This can be useful when you need to take actions in your cluster (make configuration changes and restart various elements) and do not want to see the alerts that will be generated due to those actions.

Putting a entity into maintenance mode does not prevent events from being logged; it only suppresses the alerts that those events would otherwise generate. You can see a history of all the events that were recorded for entities during the period that those entities were in maintenance mode.

Explicit and Effective Maintenance Mode

When you enter maintenance mode on a entity (cluster, service, or host) that has subordinate entities (for example, the roles for a service) the subordinate entities are also put into maintenance mode. These are considered to be in effective maintenance mode, as they have inherited the setting from the higher-level entity.

For example:
  • If you set the HBase service into maintenance mode, then its roles (HBase Master and all RegionServers) are put into effective maintenance mode.
  • If you set a host into maintenance mode, then any roles running on that host are put into effective maintenance mode.

Entities that have been explicitly put into maintenance mode show the icon . Entities that have entered effective maintenance mode as a result of inheritance from a higher-level entity show the icon .

When an entity (role, host or service) is in effective maintenance mode, it can only be removed from maintenance mode when the higher-level entity exits maintenance mode. For example, if you put a service into maintenance mode, then the roles associated with that service will be entered into effective maintenance mode, and will remain in effective maintenance mode until the service exits maintenance mode. You cannot remove them from maintenance mode individually.

On the other hand, an entity that is in effective maintenance mode can be put into explicit maintenance mode. In this case, the entity will remain in maintenance mode even when the higher-level entity exits maintenance mode. For example, suppose you put a host into maintenance mode, (which puts all the roles on that host into effective maintenance mode). You then select one of the roles on that host and put it explicitly into maintenance mode. When you have the host exit maintenance mode, that one role will remain in maintenance mode. You will need to select it individually and specifically have it exit maintenance mode.

Viewing Maintenance Mode Status

You can view the status of Maintenance Mode in your cluster by clicking to the right of the cluster name and selecting View Maintenance Mode Status.

Entering Maintenance Mode

You can enable maintenance mode for a cluster, service, role, or host.

Putting a Cluster into Maintenance Mode

  1. Click to the right of the cluster name and select Enter Maintenance Mode.
  2. Confirm that you want to do this.

The cluster is put into explicit maintenance mode, as indicated by the icon. All services and roles in the cluster are entered into effective maintenance mode, as indicated by the icon.

Putting a Service into Maintenance Mode

  1. Click to the right of the service name and select Enter Maintenance Mode.
  2. Confirm that you want to do this.

The service is put into explicit maintenance mode, as indicated by the icon. All roles for the service are entered into effective maintenance mode, as indicated by the icon.

Putting Roles into Maintenance Mode

  1. Go to the service page that includes the role.
  2. Go to the Instances tab.
  3. Select the role(s) you want to put into maintenance mode.
  4. From the Actions for Selected menu, select Enter Maintenance Mode.
  5. Confirm that you want to do this.

The roles will be put in explicit maintenance mode. If the roles were already in effective maintenance mode (because its service or host was put into maintenance mode) the roles will now be in explicit maintenance mode. This means that they will not exit maintenance mode automatically if their host or service exits maintenance mode; they must be explicitly removed from maintenance mode.

Putting a Host into Maintenance Mode

  1. Go to the Hosts page.
  2. Select the host(s) you want to put into maintenance mode.
  3. From the Actions for Selected menu, select Enter Maintenance Mode.
  4. Confirm that you want to do this.

The confirmation pop-up lists the role instances that will be put into effective maintenance mode when the host goes into maintenance mode.

Exiting Maintenance Mode

When you exit maintenance mode, the maintenance mode icons are removed and alert notification resumes.

Exiting a Cluster from Maintenance Mode

  1. Click to the right of the cluster name and select Exit Maintenance Mode.
  2. Confirm that you want to do this.

Exiting a Service from Maintenance Mode

  1. Click to the right of the service name and select Exit Maintenance Mode.
  2. Confirm that you want to do this.

Exiting Roles from Maintenance Mode

  1. Go to the services page that includes the role.
  2. Go to the Instances tab.
  3. Select the role(s) you want to exit from maintenance mode.
  4. From the Actions for Selected menu, select Exit Maintenance Mode.
  5. Confirm that you want to do this.

Exiting a Host from Maintenance Mode

  1. Go to the Hosts page.
  2. Select the host(s) you want to put into maintenance mode.
  3. From the Actions for Selected menu, select Exit Maintenance Mode.
  4. Confirm that you want to do this.

The confirmation pop-up lists the role instances that will be removed from effective maintenance mode when the host exits maintenance mode.