Is it possible for Ipsec Mikrotik with gray IP + FreeBSD 10.2 with white IP?

Question

FreeBSD

Hello! There is a Mikrotik with a gray ip with unconditional external redirection from the provider and a server with FreeBSD 10.2 with a white IP. I set up IPSec according to the manuals from Mikrotik, but naturally the tunnel does not rise and nothing gets into SAs, since this is a gray IP.
Is it even possible? If so, which way should you look?

Answer 1

Look towards ipsec nat traversal. FreeBSD supports it, I don't know about Mikrotik, but I think it should.

Answer 2

Yes. Thank you. I tried this scheme, but then already configured mikrotik fall off. Who have a real white ip. In the tcpdump logs, it said that there was no access to the ipip protocol, although everything should have been normal in theory. I will read further.

Answer 3

In this case, it is preferable to run IPSEC over the L2TP tunnel.