Certificates are tied to hostnames, and hostnames resolve to IPs. You could have a server with 50 IPv6 IPs, have a different hostname resolve to each one, and l

Certificates are tied to hostnames, and hostnames resolve to IPs. You could have a server with 50 IPv6 IPs, have a different hostname resolve to each one, and load all of the SSL certs onto the machine along with the appropriate webserver configs. You could then add IPs to the server and DNS without touching the certs. Or replace a cert without changing anything else. You don't need SNI in this scenario, you just have to ensure you add the new IPs to the server configs before updating DNS, so it will serve the correct default certificate.