Configure elasticity mode to allow the application placement controller to minimize the
number of used nodes remove nodes that are not needed. You configure elasticity mode while still
meeting service policy goals. You can configure elasticity mode to allow the controller to add a
node if the controller recognizes that a particular dynamic cluster is not meeting service policies
even when all possible servers are in use.
Procedure
- Set the
HAManagedItemPreferred_apc
custom
property to configure the application placement controller to start
on a deployment manager or a node that will not be removed. Complete
the following steps to configure the application placement controller
to start on the deployment manager:
- In the administrative console, select .
- Enter the name of the custom property as HAManagedItemPreferred_apc.
- Set the value of the custom property to true.
- Click Apply, and save your changes.
- Restart the current process in which the application
placement controller is running.
Complete the following steps to configure the application
placement controller to start on the node:
- In the administrative console, select .
- Enter the name of the custom property as HAManagedItemPreferred_apc.
- Set the value of the custom property to true.
- Click Apply, and save your changes.
- Restart the current process in which the application
placement controller is running.
- Set the
HAManagedItemPreferred_apc
and HAManagedItemPreferred_cellagent
custom
properties to configure the controllers to start on the deployment
managers of the center cell and the point cells when you enable elasticity
mode in an environment in which multi-cell performance management
is configured. Complete the following steps to configure
the application placement controller to start on the deployment manager
of the center cell:
- In the administrative console, select .
- Enter the name of the custom property as HAManagedItemPreferred_apc.
- Set the value of the custom property to true.
- Click Apply, and save your changes.
- Restart the current process in which the application
placement controller is running.
Complete the following steps to configure the cell agent
to start on the deployment managers of the point cells:
- In the administrative console, select .
- Enter the name of the custom property as HAManagedItemPreferred_cellagent.
- Set the value of the custom property to true.
- Click Apply, and save your changes.
- Restart the current process in which the application
placement controller is running.
- Enable elasticity mode.
Select .
- Select the Enable elasticity operation check
box.
- Set elasticity to either supervised or automatic mode.
- Set the timeout value.
This value defines
the allotted period of time that the application placement controller
allows the task to complete. If the task does not complete within
the specified amount of time, the application placement controller
marks the task as failed. Specify the value in minutes. The default
value is 10.
Avoid trouble: If you change the elasticity
operations timeout value in the WebSphere Application Server administrative
console or by using a wsadmin command, make the same change in the
pattern as well. When a new On-Demand Router (ODR) is requested by
the Application Placement Controller (APC), the updated elasticity
operations timeout value is not overwritten by the timeout value specified
in the pattern.
- Click Apply, and save your changes.
- Define the actions of the elasticity operations.
An
elasticity operation defines the runtime behaviors to monitor, and
the corrective actions to take when the behaviors are present. Select .
- To add additional actions to the add operation, click Add
Action....
Select the custom action from the
list of custom elasticity operation actions. If no custom actions
are defined, select.
- To add additional actions to the remove operation, click Add
action....
Select the custom action from the
list of custom elasticity operation actions. If no custom actions
are defined, select.