It's "DNS" because the problem is that at the very top of the abstraction hierarchy in any system is a bit of manual configuration.

As it happens, that naturally maps to the bootstrapping process on hardware needing to know how to find the external services it needs, which is what "DNS" is for. So "DNS" ends up being the top level of manual configuration.

But it's the inevitability of the manual process that's the issue here, not the technology. We're at a spot now where the rest of the system reliability is so good that the only things that bring it down are the spots where human beings make mistakes on the tiny handful of places where human operation is (inevitably!) required.

> hardware needing to know how to find the external services it needs, which is what "DNS" is for. So "DNS" ends up being the top level of manual configuration.

Unless DNS configuration propagates over DHCP?

DHCP can only tell you who the local DNS server is. That's not what's failed, nor what needs human configuration.

At the top of the stack someone needs to say "This is the cluster that controls boot storage", "This is the IP to ask for auth tokens", etc... You can automatically configure almost everything but there still has to be some way to get started.