To begin with, make sure that the machines whose subscriptions you want to activate are registered on the management server and available (turned on).
If you need to back up ESX(i) virtual machines, bind them to Agent for ESX(i) as described in the "Agent for ESX(i) binding" section of the "Backing up virtual machines" document. When activating the subscription for virtual machines, select the machine where the agent is running.
To activate subscriptions
Connect the console to the management server.
On the Actions menu, click Activate online backup subscriptions.
Specify the credentials to log in to the online storage.
Select any number of machines from either the Workstations or the Servers list, and then click Select subscription.
Select the type of subscriptions you want to activate for the machines. The number of the subscriptions must be at least the same as the number of the selected machines.
Click Activate now.
Perform the previous three steps for other machines you want to activate subscriptions on.
Alternatively, you can activate a subscription when the console is connected to a machine instead of the management server.