Re: VPN IPsec Down (between fortinet and pfsense)
yes so can you set it from auto and reset the ipsec vpn. Re monitor the traffic with the earlier diag diag sniffer packet.
Another command that you can and should execute after you get a response
diag debug reset
diag debug enable
diag debug application ike -1
Dump the debug output that you received from the pfsense. Also I believe you need a rule in pfsense to allow the IKE IKSAMP, ESP so you might to look at drop packets on pfsense .