NSE4 · Question #501
Which of the following statements describes the objectives of the gratuitous ARP packets sent by an HA cluster?
The correct answer is B. To notify the network switches that a new HA master unit has been elected. Gratuitous ARP packets sent by a FortiGate HA cluster after a failover notify connected network switches about the new MAC-to-IP address mapping of the active unit.
Question
Which of the following statements describes the objectives of the gratuitous ARP packets sent by an HA cluster?
Options
- ATo synchronize the ARp tables in all the FortiGate Unis that are part of the HA cluster.
- BTo notify the network switches that a new HA master unit has been elected.
- CTo notify the master unit that the slave devices are still up and alive.
- DTo notify the master unit about the physical MAC addresses of the slave units.
How the community answered
(31 responses)- A3% (1)
- B90% (28)
- C6% (2)
Why each option
Gratuitous ARP packets sent by a FortiGate HA cluster after a failover notify connected network switches about the new MAC-to-IP address mapping of the active unit.
Gratuitous ARP packets are sent out to the network to update external devices (like switches), not to synchronize ARP tables *within* the HA cluster itself.
After an HA failover, the newly elected master unit sends gratuitous ARP packets to update the MAC address tables of connected network switches, ensuring traffic destined for the cluster's virtual IP addresses is correctly routed to the new active unit.
The health of slave units is typically monitored via HA heartbeat packets, not gratuitous ARP.
The master unit already knows the physical MAC addresses of the slave units through internal HA communication; gratuitous ARP is for external network notification.
Concept tested: HA gratuitous ARP purpose
Source: https://docs.fortinet.com/document/fortigate/7.4.0/administration-guide/575308/high-availability
Topics
Community Discussion
No community discussion yet for this question.