Some time ago I landed on a website that provided a paid service that caches websites. As I understood it, the only thing I needed to do was change the DNS record of my website and point it to them. Their service would check if my website is online and direct traffic to my server. In the event my server is unavailable they would provide a cached version.
I'm not talking about the free publicly available Google cache/archive.org or a dumb CDN solution.
The problem is that I can't remember which company provided this service.