This is a step-by-step tutorial for configuring a high availability cluster (active-standby) with two FortiGate firewalls. Since almost all firewall vendors have different principles for their HA cluster, I am also showing a common network scenario for Fortinet.
Beside the HA1 and HA2 interfaces on a Palo Alto Networks firewall, there are the HA1/HA2 Backup and Heartbeat Backup options. I was a bit confused while reading the documentation of the high availability instructions since it did not clearly specify when and where to use the dedicated management port for what kind of “backup”.
Basically, it should read that there are two different ways on how to use the dedicated management for a HA Backup: the heartbeat backup OR the HA1 backup.