IPSEC with Linux is actually easier than with Windows. It's windows that has the special requirements (oh, you have NAT somewhere on the way? You are going to

IPSEC with Linux is actually easier than with Windows. It's windows that has the special requirements (oh, you have NAT somewhere on the way? You are going to deploy a registry key to all your clients to allow UDP encapsulation. And you have your gateway behind NAT? Now you cannot have your hostname in your Subject Alternate Name (otherwise mandatory), you gotta have the external IP there, potentially breaking all the non-windows clients).