I’d like to activate IPv6 on an interface without setting an address (so, it should only have a link local address… either configured manually or automatically…). How can I do this?
Why I need this? Well, I’d like to use this VyOS as default router for my network. That’s why it needs this link local address. But it should not distribute prefixes or something else, since everything behind it is configured with static IPs… but, currently I’m struggling with the question how to configure this routing stuff.
In the IPv4 world, we had a to set a static ip for the router, then configure this as “default gateway” on the servers and it worked… now, in the IPv6 world, I have some problems… either I’ve to configure my VyOS router with a static link local address so that I can set this in the server configuration or… it has to have a dynamic link local address and send an RA, but without prefix advertisement (no autonomous flag and stuff like that)… for me both options are fine, but… I cannot activate IPv6 on the VyOS interface without also activating all the prefix-auto-config stuff… and I also don’t want my router to get a public IPv6 address… it doesn’t need it and it’s only a security risk.
Oh and see? Now… when I use “show interfaces ethernet eth1”, it shows me, that it does have a link local address… but I don’t understand what caused it. What did I do/activate that it get’s it now? … is it, that because I activate DHCPv6-PD on a completely other interface, that every interface does now get a link local IPv6 address, because this activated IPv6 globally in the system? … those points are hard to understand… that’s why people always say “the system suddendly does something” or why even airline pilots are sometimes (too ofen) asking “what is it doing now??” …
would be nice to get an explanation of this behaviour…