Electronic rack locks and door sensors typically report state changes over SNMP or a vendor webhook, useful for both security and simple "was this rack opened" auditing.
Simpler door-contact sensors often bolt onto an environmental monitoring unit's generic input and report over that device's SNMP agent; smarter electronic-lock systems may have their own API instead.
A rack door opening isn't inherently critical the way a leak or an over-temperature condition is; route it as an informational or warning-level event unless it happens outside a scheduled maintenance window, which you can flag through Linivo's maintenance-window suppression.
If your access-control system can export logs or webhooks, pairing "door opened" with "who badged in" turns a bare event into something you can actually act on if it happens unexpectedly.