FORTIGATE and HPE sever with NIC in Fault Tollerant

Hi all,

 who know how can i configure the interface type on my firewalls (in ACTIVE STAND-BY) in order to implement a network failure in scenario shonw below?

Using Hardware switch after period the connection goes down. I have to unplug the cable from STAND-BY Firewall to restore the communication between servers.

Can some one help me?

Best Regards

Archi