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Templates contain Application names, Items, Triggers, Graphs, Screens, and Discovery Rules thatare that are used to apply to one or more hosts.
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Changing a template will propagate to all linked hosts.
Unlinking a host from a template will just unlink the items, the items will still exist on the host unless you unlink and clear.
It is recommended that Templates should be stored in the appropriate host group of the owner.
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Active Check is data being sent from the Agent to the Server.
Unlinking a host from a template will just unlink the items, the items will still exist on the host unless you unlink and clear.
Make sure your actions only affect the host group you are working with and the user/user group you are targeting.