It depends if the MX is the VPN terminator, or the termination is behind the MX. That's why I mentioned NAT-T. ... View more

What do you exactly want to achieve? MX doesn't route unencapsulated ESP traffic, but NAT-T works without any problem, hence UDP is the protocol to allow. ... View more

I had a similar issue towards an Azure VPN Gateway. Moving to IKEv1 solved the flapping. ... View more