...to generate the heartbeat message to the Acquia network?
To generate a heartbeat the Acquia Agent module needs to be enabled and then the cron.php file on your site needs to be called. Generally this is accomplished by having your server call your site /cron.php like http://example.com/cron.php. The Getting Started guide has a little information about this and can be found on the download page https://acquia.com/downloads. You can also setup Acquia Network to call cron.php for you if the server is accessible from the internet.
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Acquia Client Advisory Team