[Babel-users] Send: Cannot assign requested address

[Bobby]

Thank you Johannes and Juliusz,
This all seems very odd. I wonder if perhaps Raspbian has done something to partially break ipv6?

> Weird.  Linux should assign a link-local address shortly after the link is
> established.

When booting the Pi, all wlan interfaces are assigned a link-local ipv6 address. After taking the wlan1 interface down, switching to ad-hoc mode, and bringing the interface back up, the link-local ipv6 is lost and does not return automatically.

> ping ff02::1%wlan1


Attempting to ping ff02::1%wlan1 (the usb wifi interface that has been switched to ad-hoc, and that loses it's link-local ipv6) does not work. First, prior to manually adding a link-local address, it will say:
     ping: sendmsg: Network is unreachable

and then after manually adding a link local address via the command mentioned on github, it will say:
     ping: sendmsg: Cannot assign requested address

Attempting to ping ff02::1%wlan0 (wlan0 is the Pi's built-in wlan, and currently boots up connected to my home wifi access point) works correctly. There are many responses from devices on my home network. This interface was never brought down and therefore kept it's automatically assigned link-local address. I presume this means that Raspbian at least supports ipv6 in some capacity.

I have made no changes to Raspbian. It's a fresh install. All that was done was an `apt update && apt upgrade` along with compiling and installing babeld-1.10 as well as generate-ipv6-address. I'm at a complete loss as to why it's behaving this way. I still have hope that it is some simple thing that I have overlooked.

Thanks,
Bobby