site to site VPN, IKEv2 and Nat-T issue, Impact of disabling "support Nat-t" on Gateway

[Daniel_Bourne]

So I have a site to site VPN with a Cisco ASA device from my Clustered 5100 firewalls.  The tunnel comes up, but they cannot see any traffic coming from my side.  I believe the issue is with IKEV2 and the "support Nat-t" on Gateway according to SK5390.

I have about 40 site to site VPNS configured and only this one is using IKEv2. We also have checkpoint mobile clients connecting in to our 5100.  What is the impact if I disable the option to "Support NAT-T" on the gateway for the checkpoint mobile clients?  Is there a way to disable NAT-T for just one site to site VPN?

Thanks,

[G_W_Albrecht]

Oh, you have a 5100 ! I just worked 20min to answer your question as if you had a 1500 SMB ☹️. Bad place, to post it on SMB...

[Daniel_Bourne]

Sorry, I thought that was the correct area.  Not sure how to change that or delete the post unfortunately.

[G_W_Albrecht]

Has been relocated thanks to @PhoneBoy i guess 😎 -  that is how it is done...

[PhoneBoy]

Yes, threads can only be moved by admins 🙂

[Timothy_Hall]

My recommendation for interoperable VPNs is to try IKEv2 with them, but do not hesitate to return to IKEv1 if there are any problems.  I'm not sure where you got that SK number, but I think this is the one you want:

sk165003: When Security Gateway initiates VPN tunnel with 3rd Party peer using IKEv2, VPN tunnel is ...

Also possible that your situation is a known bug on the Cisco side, see here:

VPN issue with IKEv2 and Cisco ASA

[the_rock]

Message me privately, we can do remote session...I hope I would be able to help you.

Andy