Unfortunately the other firewall is a zywall managed by another company at € 70 per call.
I have already installed a Nethserver Appliance (only for vpn in bridge connections), i'm waiting to move all the services on the NS and I will use the new VPN module.
thanks @pike I did not see the post, in fact until a few days ago it worked perfectly
But sorry, the log says clearly that you do not expect it
Unexpected STRING [Protocol]
It can simply be the uppercase letter?