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When a service is added to Cloudera Manager, either through the installation or upgrade wizard or with the Add
Services workflow, Cloudera Manager automatically sets the configuration properties, based on the needs of the service
and characteristics of the cluster in which it will run. These configuration properties include both service-wide
configuration properties, as well as specific properties for each role type associated with the service, managed through
role groups. A role group is a set of configuration properties for a role type, as well as a list of role instances associated
with that group. Cloudera Manager automatically creates a default role group named Role Type Default Group for
each role type. See Role Groups on page 48.
Changing the Configuration of a Service or Role Instance (Classic Layout)
1. Go to the service status page.
2. Click the Configuration tab.
3. Under the appropriate role group, select the category for the properties you want to change.
4. To search for a text string (such as "snippet"), in a property, value, or description, enter the text string in the
Search box at the top of the category list.
5. Moving the cursor over the value cell highlights the cell; click anywhere in the highlighted area to enable editing
of the value. Then type the new value in the field provided (or check or uncheck the box, as appropriate).
• To facilitate entering some types of values, you can specify not only the value, but also the units that apply
to the value. for example, to enter a setting that specifies bytes per second, you can choose to enter the
value in bytes (B), KiBs, MiBs, or GiBs—selected from a drop-down menu that appears when you edit the
value.
•
If the property allows a list of values, click the icon to the right of the edit field to add an additional field.
An example of this is the HDFS DataNode Data Directory property, which can have a comma-delimited list of
directories as its value. To remove an item from such a list, click the icon to the right of the field you want
to remove.
6. Click Save Changes to commit the changes. You can add a note that will be included with the change in the
Configuration History. This will change the setting for the role group, and will apply to all role instances associated
with that role group. Depending on the change you made, you may need to restart the service or roles associated
with the configuration you just changed. Or, you may need to redeploy your client configuration for the service.
You should see a message to that effect at the top of the Configuration page, and services will display an outdated
configuration (Restart Needed), (Refresh Needed), or outdated client configuration indicator. Click the
indicator to display the Stale Configurations on page 28 page.
Validation of Configuration Properties
Cloudera Manager validates the values you specify for configuration properties. If you specify a value that is outside
the recommended range of values or is invalid, Cloudera Manager displays a warning at the top of the Configuration
tab and in the text box after you click Save Changes. The warning is yellow if the value is outside the recommended
range of values and red if the value is invalid.
Overriding Configuration Properties
For role types that allow multiple instances, each role instance inherits its configuration properties from its associated
role group. While role groups provide a convenient way to provide alternate configuration properties for selected
groups of role instances, there may be situations where you want to make a one-off configuration change—for example
when a host has malfunctioned and you want to temporarily reconfigure it. In this case, you can override configuration
properties for a specific role instance:
1. Go to the Status page for the service whose role you want to change.
2. Click the Instances tab.
3. Click the role instance you want to change.
4. Click the Configuration tab.
5. Change the configuration values as appropriate.
6. Save your changes.
You will most likely need to restart your service or role to have your configuration changes take effect.
16 | Cloudera Administration
Managing CDH and Managed Services