[c45y]

Probably an expectation for floating IPs for load balancing instead of DNS.

Relatively simple inside a network range you control but no idea how that works across different networks in geographical redundant setups

[deceptionatd]

Agreed; I have no idea how you'd implement that across multiple ASNs, which is definitely a requirement for multi-cloud or geo-redundant architectures.

Seems like you'd be trying to work against the basic design principles of Internet routing at that point.

[_bernd]

You can configure your assigned network numbers that other AS are allowed to announce certain networks of your own. Not uncommon for in examples authoritative name server addresses.

[deceptionatd]

TIL, I always thought IP:ASN mappings were 1:1.

[_bernd]

With cloud providers and such the wording could also be "bring your own address".

[preisschild]

Anycast pretty much