Using HA log messages to determine system status
When the FortiGate unit is in HA mode, you may see the following log message content within the event log:
type=event subtype=ha level=critical msg= “HA slave heartbeat interface internal lost neighbor information”
OR
type=event subtype=ha level=critical msg= “Virtual cluster 1 of group 0 detected new joined HA member”
OR
type=event subtype=ha level=critical msg= “HA master heartbeat interface internal get peer information”
The log messages occur within a given time, and indicate that the units within the cluster are not aware of each other anymore. These log messages provide the information you need to fix the problem.