What is one way that MX security appliances achieve automatic failover and high availability?

Cisco Meraki MX security appliances support high availability through a feature called warm spare, which uses the Virtual Router Redundancy Protocol (VRRP). When two MX appliances are configured in warm spare mode, one acts as the active device and the other as a standby. VRRP advertisements monitor the health of the active device.

If the active appliance fails, the standby device automatically takes over routing and firewall functions, ensuring minimal disruption. This design is easy to configure and provides seamless failover and redundancy, essential for business continuity at the branch level.

Thus, the correct answer is C, as VRRP-based warm spare mode is the officially supported method for achieving high availability with MX appliances.

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