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Email: email address of the contact, used to send escalations, etc, if configured. Multiple email addresses may be used if separated by a comma.
Location: location of your contact. Not sure if this lines up with System -> System Configuration -> Locations at all or if it has any functional uses. Line this up with the locations table in System configuration and this can be used with escalations and the location for a given device (either set on the device coming through SNMP or in NMIS).
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