If the system fails to switch some sensors into the guarding mode, site's users will receive the push-notification in the app and the entry will appear in the event log. The entry will contain the list of sensors to check, the date and time of the failure.
If you confirm the guard enabling with the exception of some sensors, then you will also receive the push-notification and the entry will be added to the event log.
If the user is enabling the guard using the Livi Key Fob or Livi RFID control panels, then the group guard will not be enabled, if the system fails to switch some sensors into the guarding mode.