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If you are using the Automated Installer for installing Agents in a silent mode, you can add to the installation commands an Agent option, which will assign the new Agent to a certain Build Group upon its launch.
Note: For more information about using the Automated Installer, see: Performing a Silent Installation
The installation option that allows you to assign an Agent to a Build group is Group={Group name}. This is an Agent option, and it is used as follows: /Agent:Group={Group name}
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