This section describes FortiGate-VM and VMware ESXi performance optimization techniques that can improve your FortiGate-VM performance by optimizing the hardware and the VMware ESXi host environment for network- and CPU-intensive performance requirements of FortiGate-VMs.
In addition, the MTU of the port4 interface is set to be compatible with the OpenStack 10 environment, which by default, has an MTU of 1446. (In the user_data file, the MTU of port4 is set to 1400.) Using the same MTU setting as the OpenStack 10 environment enables the HA heartbeat interfaces to communicate effectively over the ha-sync network.
See these pages for more information on RedHat OpenStack networks and MTU values: