How to purchase SSL certificate just for the Fortigate 30E to use for an SSL VPN tunnel?

[wm999]

Hello all,

I bought a Fortigate 30E solely for the purpose of setting up a VPN tunnel to my residential home office for use while I'm traveling overseas because I'll need access to gmail, etc. while in Asia (and I don't want to use a VPN subscription service such as NordVPN for accessing sensitive business accounts). 

I was initially going to try using a Let's Encrypt SSL certificate but another member of this forum told me that the Fortigate 30E doesn't support that. So it's not clear to me how I can obtain an SSL certificate that will work with the Fortigate 30E VPN tunnel. 

How can I do this, any ideas? If I just tried to buy an SSL certificate for a dormant domain that I own through Google Domains, that wouldn't work, would it? Because I think the certificate has to be specifically associated to the Fortigate somehow when it's first created?

[Antoine]

You can certainly upload a full certificate along with its private key (which has to be in PKCS#12 format, also known as .pfx) to the FortiGate. So if you can extract your dormant-domain certificate to PKCS#12 format and it matches the hostname (as seen from the internet) of your router, you could use it.