Whitelisting LE IP addresses / ranges in Firewall

Server
6

If access is going to be restricted to specific addresses, that signals it might be a closed system. The owner may actually be better off using a self-signed certificate or making an internal CA that the approved clients can trust. Let’s Encrypt is great for allowing users to trust an otherwise anonymous site, but if there’s already access controls it’s not as big of a deal since both sides can be managed.