Technical Tip: Board failover tolerance in FortiGate Chassis

When chassis FPM/FPCs are down, the HA failover will happen as per the article below:

FortiGate6000F: Primary FortiGate-6000 selection with override enabled,

FortiGate7000E: Primary FortiGate 7000E selection with override disabled (default).

FortiGate7000F: Primary FortiGate 7000F selection with override disabled (default).

However, the blade tolerance command can be set in some cases under the HA setting to prevent HA failover when a minimal blade failure:

chassis-XXX (global)# config system ha
chassis-XXX (ha)# set mode a-p
chassis-XXX (ha)# set board-failover-tolerance ?
board-failover-tolerance Enter an integer value from <0> to <9>.

Note: The integer value varies depending on the model. The above 0-9 is an example from a FortiGate 7121F, and this model has 10 FPMs.

For example, if we set "board-failover-tolerance" to 3, then when 3 FPMs are down, only HA will failover.