How to use any address from IPv6 subnet?

Question

linux

There is a /64 network on the VPS. There are a lot of addresses there, but in order to use one of them (in ping / curl), you need to add it separately to the interface. How can this be avoided? All the addresses from the network are needed at the same time.

All instructions, which is actually only one ( https://blog.vpsville.ru/blog/howto/133.html ) does not work, unfortunately.

OS - CentOS 7.

PS I didn't think that there would be such a problem at all. The host can't help either.

Answer 1

It is logical that in order to use the address in outgoing packets, it is "recommended" to have it on some interface - otherwise, how will your gateway understand where to send the response? You know, ARP requests and all that...
If you just need to send packets with random content, there are separate utilities for that.

Answer 2

Why doesn't it work. It works, only it is necessary that the application supports specifying a specific IP as outgoing.

curl -L --interface '2a03:6f00:5:1::b6c8:f350' https://ya.ru/

ping6 -I '2a03:6f00:5:1::b6c8:f350' ya.ru
And if we are talking about the server, then the server must be able to bind to an unassigned IP.
Well, on the interface that looks at the Internet, there must be an IP from this subnet. That is, you need to correctly configure IPv6 on the machine, make sure that everything works, for example, ping ya.ru or google.com and register a route that would point to the lo interface, as in that instruction.
And forwarding must be enabled. Or not...

Answer 3

https://github.com/DanielAdolfsson/ndppd.git
This will help you