Fortigate 60F and Cisco ACI BPDU issue

[fortigeorge]

Hi,

I'm trying to connect a Fortigate 60F internal port to a Cisco N2K FEX switch as a management interface so I can manage it remotely through our lab setup.

The problem I'm having is once connected the switch is putting the port into an 'bpdu-guard-err-disabled' state.

I just wanted to confirm that an out of the box Fortigate 60F firewall in NAT mode wouldn't be sending spanning tree BPDU's out of the internal interface?

What I need is for this 'internal' port to behave like a regular access port.