Is it possible to specify link-local address and avoid EUI-64 addresses?

[eddy]

A couple IPv6-related questions:

1) Is there any way to specify the link-local addresses and avoid the EUI-64 auto-generated addresses?

e.g. I'd prefer to see fe80::1%igb0 as my link-local instead of fe80::4242:42ff:fe42:4243%igb0

2) Similarly, when an interface's IPv6 Configuration Type is set to Track Interface, is there a way to have the tracked-interface always use the ::1 address (for example) of the delegated prefix instead of the prefix plus the lengthy EUI-64 address?

I'd prefer to use "sane" addresses for my gateways if possible.

Thanks for any suggestions!

[franco]

Hi eddy,

You can add a Virtual IP for each interface. In case of reusing fe80::1 I wrote a small patch to acomplish that...

https://github.com/opnsense/core/commit/2b7beb78b

# opnsense-patch 2b7beb78b

So you can't scrub the auto-assinged link-local, but add more if you want. Does that fit your use case?


Cheers,
Franco

[eddy]

I had not considered using a Virtual IP like this. Are there any examples showing this configuration? (I have not had the need to use Virtual IPs in my configuration yet, so am unfamiliar with the implications to existing rules, for example.)

Is this only for link-local addresses (#1 in my post) or do a Virtual IPs also make it possible to specify the host portion of a delegated prefix for the firewall’s tracked interface address (#2 in my post)? (Right now, the firewall always uses an EUI-64 address in the PD.)

Thanks for the continued insights!

[Greelan]

I use Virtual IPs for ULAs. AFAIK you can’t use prefix tracking in the Virtual IP configuration - you have to specify the full address

[franco]

Prefix tracking could be something that works there if implemented.. only unsure how to remove invalid addresses and distinguish between auto-assigned.


Cheers,
Franco

[eddy]

Prefix tracking in VIPs sounds great. 👍 Hope there's some workable logic that allows that to get implemented. 😍

Once I've assigned an "IP Alias" VIP (like fe80::2) to a LAN interface, how do you get that IP Alias address advertised as the IPv6 default route for IPv6 clients? 🤔