IPv6 "bloat" history

Fri Apr 1 13:47:08 UTC 2022

Hello Ohta-san

> > - there's no way to know if 2 locations are OK (anycast)
> 
> If you mean IPv6 anycast to allow 2 or more hosts sharing an anycast address,
> it is just broken not useful for any purpose and ignored.

One case I have in mind is when one wants to bundle multiple physical interfaces as one logical P2MP interface that reaches different routers, e.g., for server multihoming. 

There's a single owner and a single address, but it is presented to both routers on different physical interfaces and can be routed to any of those. Then the routers inject the address in some overlay and may fight unless they realize that they work on behalf of the same end point.

Basically I'm talking about a proper L3 abstraction for cases where LAG / Etherchannel are used today. K8S needs a unique IP like that.

> Instead, IPv4 style anycast is widely deployed for IPv6.

I guess you mean the one we configure on a server loopback for load balancing? Certainly. The end result is the same for the routing (weighted ECMP) so for all I know we can use the same signals.

Keep safe;

Pascal