Troubleshooting Tip: IKE negotiation error between FortiGate and Sonicwall

[janonuevo]

Description	This article describes how to deal with the IKE negotiation error between FortiGate and Sonicwall.
Scope	FortiOS v7.
Solution	CLI commands: diagnose debug reset diagnose vpn ike log filter clear diagnose vpn ike log filter name "IPsec_Tunnel_Name" diagnose debug application ike -1 diagnose debug enable If the IKE debug message contains the error 'probable pre-shared secret mismatch'. Solution: Check if the 'Peer ID' on FortiGate matches the 'Local IKE ID' on Sonicwall. On FortiGate: On Sonicwall: If the IKE debug message contains a 'malformed responder cookie'. Solution: (If FortiGate is behind the NAT device). Check if the 'Peer IKE ID' configured on Sonicwall is the IPv4 interface IP of FortiGate connected to the uplink device. On FortiGate:                                                                                    On Sonicwall: