question about HA

[GiuseppeB]

Hello,

following this configuration scenario, what I configured is a redundant that looks towards the primary router and the secondary router and put the monitor of this redundant under it, in case a link of this redundant goes out it automatically switches it to the secondary or does the primary remain active?

PRIMARY

config system ha
set group-id 2
set group-name "FGT-HA"
set mode a-p
set hbdev "ha1" 50 "ha2" 60
set session-pickup enable
set override enable
set priority 250
set monitor "Redundant"
end

SECONDARY

config system ha
set group-id 2
set group-name "FGT-HA"
set mode a-p
set hbdev "ha1" 50 "ha2" 60
set session-pickup enable
set override enable
set priority 150
set monitor "Redundant"
end

BR,

Giuseppe

[nradia_FTNT]

Hi Giuseppe,

Higher priority unit becomes primary.

Here is another useful KB article that explains selection criteria for primary unit:

https://community.fortinet.com/t5/FortiGate/Technical-Tip-FortiGate-HA-Primary-unit-selection-proces...

Following is for port monitoring:

https://docs.fortinet.com/document/fortigate-7000/6.2.12/fortigate-7000f-handbook/744105/link-failov...

[sprashant]

Hello @GiuseppeB 

To answer you question, yes, the monitored interface if goes down, the failover should occur, (meaning, the secondary device would become active). However, you have put the HA links itself here, I am not sure if you want them specifically to be monitored or not. In general, monitored interface are usually the ones which are used to traverse the traffic from firewall e.g. LAN to WAN or vice versa.

Resource to review : https://docs.fortinet.com/document/fortigate/6.0.0/handbook/666653/primary-unit-selection-with-overr...

[GiuseppeB]

Hello,

thanks for reply, the redundant interface is composed by 2 physical interface, so if one these interface goes down, with this configuration and without link monitor, ha will switch to secondary unit?

[Toshi_Esumi · Accepted solution]

No. A "redundant" interface goes down only when all member interfaces go down. Therefore, it wouldn't trigger HA primary selection when only one member link goes down while the others are up.

Toshi

[Toshi_Esumi]

I still recommend to refer to the 6.0.0's handbook for the a-p HA operation. This flowchart visualizes it undoubtedly.
https://docs.fortinet.com/document/fortigate/6.0.0/handbook/123439/primary-unit-selection-with-overr...
Its newer versions are more descriptive but losing visual clearness.

Toshi