If a server that is part of a fail-over cluster and also runs SCOM 2012 agent, you may get the following alert:

Alert: Agent proxy not enabled
Last modified by: System
Last modified time: 8/10/2015 3:53:20 PM
Alert description: The agent was not able to submit data on behalf of another computer because agent proxy is not enabled. Details:Health service ( server-name ) should not generate data about this managed object ( Microsoft.Windows.Computer ).

The agent will notice the server is part of a cluster and will attempt to retrieve additional information about the cluster, which is not allowed by default.

To resolve, follow these steps:

1. In Operations Manager, go to Administration.
2. In the Agent Managed view, find and right-click the agent, then click Properties.
3. On the Security tab, enable Allow this agent to act as a proxy, then click OK.