Policy Manager Users Guide

Intended for use with Cassatt Active Response Standard Edition, Premium Edition and Data Center Edition V5.1.

This document is for all users of Cassatt Active Response Policy Manager. It describes behaviors in Policy Manager, and interactions between the Admin and Tier Manager roles.

What is Policy Manager?

Policy Manager is part of the Cassatt Active Response software suite. Cassatt Active Response maintains service levels for your business applications for normal power operations, and reduces data center power consumption by powering servers off when not in use. Policy Manager is the Cassatt Active Response tool for creating and scheduling power policies.

About feature packs

Policy Manager works with Cassatt utility company feature packs by receiving event notifications from the utility companies and activating policies in response to the events; this results in additional power savings or rebates. If you are using a utility company feature pack with Policy Manager, you’ll need installation and operations documentation from the Info Central Feature Packs page at http://www.cassatt.com/infocentral/FPindex.php.

Power policies and scheduling

Power polices are editable configurations that can have two components:

• Tier settings – defines the service levels for groups of servers (called tiers) when the policy is invoked on or off, or running at a specified operational target. Tier settings are defined in the next table.
  
  

  Setting	Definition
  Include Yes/No	"Include Yes" allows the tier to participate in a Recurring or Once power policy with the values specified for the tier; “Include No” means the tier will not be included in the power policy. The default for a new tier is Include = No. Best Practice: Tier Managers should review tier settings prior to the next power policy execution to make sure the tier has the expected settings.
  Power Off/On	"Power On" allows you to select the number of nodes to remain powered on (target) when the policy is in effect. “Power Off” powers off all nodes when the policy is in effect.
  Idle Timer Off/On	The idle timer deactivates the tier automatically when the tier is idle for a specified period of time, as defined within the Cassatt Active Response Controller. If the timer is off, you can turn it on only if the parameters for the timer have been defined within the Cassatt Active Response Controller. Once the idle timer has deactivated a tier, you can reactivate it using a schedule or by controlling the tier directly. Both of these are described later in this document.
  SLA type	The SLA type indicates how capacity is set on the tier: node-based SLAs set capacity in number of nodes; load-based SLAs set capacity based on a measure of workload. If the policy is set to node-based, you can set it to load-based only if the parameters for load-based have been defined in the Cassatt Active Response Controller.
  Minimum	The minimum is the number of nodes needed for the application. The target or node limit value must be between the minimum and maximum (see below).
  Target	In a node-based SLA, the target is the number of servers that should run for a particular power policy. So you’ll select a lower target when your intention is to reduce power usage, and a higher target for policies that represent the normal operational state.
  Node Limit	The node limit for a load-based SLA is used in the same way as the target for a node-based SLA, but it has a slightly different result. With a load-based SLA, Cassatt Active Response is changing the number of active nodes in a tier dynamically based on workload measurements. Setting the node limit caps the number of nodes that can be active when a particular policy is in effect. So, to reduce power consumption, you’ll set a lower node limit. For normal operations, the node limit is higher, perhaps even equal to maximum nodes. The actual number of active nodes varies between minimum and the node limit.
  Maximum	The maximum is a read-only field that displays the largest number for either the target or node limit.

  
  
• Schedules – defines when a policy is invoked. Each policy can have multiple schedules, and each schedule can have one of the following execution types:
  • Daily, weekly, monthly (recurring) – for example, an Admin might create a power policy to shut down specific servers on Sundays.
  • Once – for example, your site may have a pre-negotiated power policy with a utility company to reduce server power at particular times or on-the-fly in order to achieve rebates or savings.
  • Now – for example, an Admin might have a power policy to shut down all servers to handle an emergency or disaster.

Managing tier power

If you just want to turn tiers on or off, select the tiers from the tier list and then select Tier actions > Power On or Tier Actions > Power Off.

Controlling tiers

If you don’t want to define a policy for reuse via a schedule, but only want to control tier capacity levels on an immediate basis, you can change tier settings directly. Just follow these steps:

1. Select the tiers you want to control from the tier list and select Tier actions > Advanced Control.
2. Set each tier as desired.
3. Alternatively, if you want to apply the same settings to a group of tiers, click Batch Change.
   
   Select the settings to apply to all of the tiers you selected for advanced control, then click Apply Changes.
4. When you are finished with your settings, click Okay.
   
   Policy Manager applies your selections.
   

User roles

Policy Manager supports three types of users: Viewers, Tier Managers, and Admins. The following table summarizes Policy Manager roles and privileges.

Admin role: details

Admins are essentially superusers who can add/change/delete anything in Policy Manager. Admins are responsible for power polices, schedules, and users. Because Admins can change tier settings set by Tier Managers, and override power policy schedules, email notification for each tier is recommended so Tier Managers are informed of changes. Also, because Admins can change each other’s settings, it is important for Admins to coordinate tasks.

Tier Manager role: details

Tier Managers are assigned one or more tiers that run applications. Because Tier Managers have knowledge of the applications on the servers in the tiers, their primary role in Policy Manager is to:

• Include tiers in power policies when it’s appropriate, and not include them when it’s inadvisable.
• Determine the target number of servers to keep running when tiers are included in power policies. Likewise, determine the node limit for tiers that use load-based SLAs.
• Control tiers immediately, except for tiers that are participating in a policy that is currently active and locked.

Tier Managers can view all tiers, policies, and schedules in Policy Manager, but can change settings only in tiers for which they are assigned (and if the policy is not locked by the Admin). Only one Tier Manager can be assigned to a tier; but Tier Managers can be assigned multiple tiers.

Tier Managers need to know all of the power policies and schedules that they participate in, and how each policy affects their assigned tiers.

Viewer role: details

Viewers are limited to viewing tiers, policies, and schedules, and cannot make changes to any operational setting in Policy Manager.

Policy Manager: what you should know

The following table answers common questions about Policy Manager, including functionality and behaviors that affect both Tiers Managers and Admins.

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