Fortigate VCluster and LACP

[Alpha7]

Hi

When 2 Fortigates in A-P cluster and configuring LACP, Fortinet recommends to configure 2 LACP trunk on switch. one for the ports terminating on master and second one for ports terminating on Slave firewall. Otherwise, we may need to use lacp-ha-slave command. Is that correct when we use VCluster as well?

Thanks

[lobstercreed]

I will caveat my answer with the fact that I have no personal experience with exactly this, but...

Between reading the documentation and considering how LACP works, I believe you are 100% correct.

[Alpha7]

Thanks lobstercreed

To make it clear; if there is no VCluster configuration and 2 port channels configured on switch to Fortigate master and slave, I expect slave unit port channel is also in negotiated and established state. As both port channels are identical, how does the switch know on which port channel it should send the traffic? if it is based on ARP reply, what will happen if fortigate is running on transparent mode?