What is the least configuration to set up HA?
What is the configuration prerequisite to successfully establish HA status on nodes?
Check if the heartbeat links are configured & connected properly:
Does heartbeat work in layer 2 or layer 3?
Will HA nodes use physical MAC address or virtual MAC address for communication?
How to manage HA nodes, especially the secondary nodes via SSH or GUI?
Does FortiWeb synchronize session information in HA mode?
Common Troubleshooting Steps
Troubleshooting HA issues when FortiWeb nodes are deployed on Hypervisors - Extra configuration on ESXi for HA deployment
HA Status issue 1 - All nodes are Primary
HA Status issue 2 - Unexpected switch over
Traffic drops down in HA environment
HA Synchronization issues