Possible yes. Cost effective / valid business case probably not. Every extra 9 is diminishing returns: it’ll cost you exponentially more than the previous 9 and money saved from potential downtime is reduced. Like you said 32 seconds of downtime, how much money is that for the business?

You’re pretty much looking at multiple geographically diverse T4 datacenters with N+2 or even N+3 redundancy all the way up and down the stack, while also implementing diversity wherever possible so no single vendor of anything can cause you to not be operational.

Even with all that though, you’ll eventually get wrecked by DNS somewhere somehow, because it’s always DNS.

It’s really hard. And really expensive. I used to work in five nine environments, life or death type use cases, and my rule of thumb was that you double your cost for every extra nine you add.

When we got to five nines it was multiple hot standbys with a custom control and orchestration plane - literally custom hardware we had to build. This was for local installations, so not modern cloud environments (it was over a decade ago), but many of the challenges are similar, like session handling, transmission replay and caching, locking, clashing, routing, jitter, latency etc.