Simpler. Maybe we start with a "wss://IP" in a "connect" tag? You just need to push that replaceable event to all other relays. Then a client connecting with one of them can see the IP change and update it's records accordingly.
Discussion
what do you think about this: kind 30053 meaning nostr name system (NNS).
tags:
[['d', 'nos.lol.nns.'], ['A', '88.198.51.48'], ['AAAA','ip:v6']]
in case there are multiple servers available in different continents:
[['d', 'nostr.mom.nns.'],
['A', '5.78.89.174'],
['A', '88.198.51.252']]
Then client can do pings and connect whatever it wants.