Since FortiOS 5.x the VDOM enable feature, which was on the GUI under System -> Dashboard -> Status -> System Information widget, is missing in the SOHO models.
To enable it we need to log-in into the CLI:
FGT # config system global
FGT (global) # set vdom-admin enable
FGT (global) # end
You will be logged out for the operation to take effect
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