sure. I use OpenBSD, BUT THE Idea is the same. It’s a little more involved to setup, as you either need a routing daemon, or you need to tell openvpn that there is a network behind your ‘client’, and setup some static routes.

Thanks For answering, might be possible to create a new vm inside esxi and install pfsense as “router”? After that create site to site vpn from pfsense to my vps, and finally exchange will be installed in dhcp of pfsense, thanks!

Yep, that is basically it. I sent from having the OpenVPN client on my Exchange server to making a VM act as a VPN router, but you’ve got the basic idea. The VPS runs postifx, and spools email and forwards it to my exchange server. If the Exchange server is offline, it’ll just spool to disk.

And even more aggressive, I could put the Exchange server on my laptop, and travel around with it.

You’ll just want a VPS where they can set the reverse DNS record.

So you had VPS and deployed on it openvpn as server, back home you had your Win machine with exchange on it, you used openvpn client on the Win box? I would like to have a similar setup, maybe you can give me some tips, my setup is: VPS with static ip will be frontend and back home I have dynamic IP, so I will make openvpn server on the VPS and the client will be the one from home, so VPS Home ESXI(Win server). Also I would like to implement the postfix on VPS in case vpn link goes down.

I don’t know as I dont run it open on the internet. and I front the exchange server with something modern, so it never directly touches it.

it just talks smtp, postfix does all the thinking.