In Orchestrator, activities are the building blocks of runbooks. Each activity performs a specific task when it runs. To use an activity in a runbook, drag an activity from the Activity pane to the Runbook Designer workspace, configure its properties, and then link it to other activities. After an activity has run, it invokes any other activities to which it is linked.
For additional help, please refer to the on-line documentation for System Center 2012 - Orchestrator.
For information about different types of activity properties, review the following topics.
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Build automatic retries.