FortiGate
FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.
alwis
Staff
Staff
Description This article explains about IPSec site-to-site VPN between FortiGate and Sonicwall fails with error message 'ignoring unencrypted INVALID-COOKIE'.
Scope

 FortiGate, IPSec

Solution

Topology

<< Fortigate -> NAT Router ->IPsec -> Sonicwall >>

 

IPsec VPN failed to established when Sonicwall pointing to dynamic IP [i.e FortiDDNS]. Debug output on FortiGate  shows, after second message is received by initiator 'ignoring unencrypted INVALID-COOKIE'  and retransmit.

 

To address this issue, on Sonicwall side change the Peer ID [IPV4 Address] to be the FortiGate's private IP which is facing the NAT Router. 

Contributors