What can the administrator do to fix this problem?

An administrator has configured two FortiGate devices for an HA cluster. While testing HA failover, the administrator notices that some of the switches in the network continue to send traffic to the former primary device.

What can the administrator do to fix this problem?
A . Configure remote link monitoring to detect an issue in the forwarding path.
B. Configure set send-garp-on-failover enable under config system ha on both cluster members.
C. Verify that the speed and duplex settings match between the FortiGate interfaces and the connected switch ports.
D. Configure set link-failed-signal enable under config system ha on both cluster members.

View Answer

Answer: D

Explanation:

Virtual MAC Address and Failover – The new primary broadcasts Gratuitous ARP packets to notify the network that each virtual MAC is now reachable through a different switch port. – Some high-end switches might not clear their MAC table correctly after a failover – Solution: Force former primary to shut down all its interfaces for one second when the failover happens (excluding heartbeat and reserved management interfaces): #Config system ha set link-failed-signal enable end – This simulates a link failure that clears the related entries from MAC table of the switches.