The question of how to create a static ipv6 but with advertised prefix has already been asked here (the solution appears to be set token), but I'd like to understand exactly what is happening in my setup.

My system natively uses NetworkManager, but I'd like to implement the changes through ifupdown. I created a /etc/network/interfaces file with the following config

auto wlp2s0 allow-hotplug wlp2s0

iface wlp2s0 inet dhcp

iface wlp2s0 inet6 auto
address ::be70:f1ic:a1a1:d502/64
accept_ra 2 privext 0

When I start the networking daemon after creating this file, two addresses are added to the wlp2s0 interface, one global dynamic mngtmpaddr and one global dynamic mngtmpaddr noprefixroute (in addition to the original ones, which include on global dynamic, one privacy extension and the link one), neither of which has the prefix I wanted to fix. Furthermore, in this stage I am not able to access internet (actually, it appears that existing connections keep working while new ones cannot be stablished).

And if I reboot the system (I believe restarting NetworkManager may be enough but am not sure) my wireless adapter is not even able to start (the wlp2s0 interface stays down with no carrier).

Now, to my questions:

1. I know that the proper way to do what I want is with a token, but why exactly does my config does not fix an IP to have my suffix?

2. Why do I get two new addresses, one with noprefixroute and one without, instead of only one?

3. Why rebooting the kernel kills the interface?

I appreciate any insights!

The question of how to create a static ipv6 but with advertised prefix has already been asked here (the solution appears to be set token), but I'd like to understand exactly what is happening in my setup.

My system natively uses NetworkManager, but I'd like to implement the changes through ifupdown. I created a /etc/network/interfaces file with the following config

auto wlp2s0 allow-hotplug wlp2s0

iface wlp2s0 inet dhcp

iface wlp2s0 inet6 auto
address ::be70:f1ic:a1a1:d502/64
accept_ra 2

privext 0

When I start the networking daemon after creating this file, two addresses are added to the wlp2s0 interface, one global dynamic mngtmpaddr and one global dynamic mngtmpaddr noprefixroute (in addition to the original ones, which include on global dynamic, one privacy extension and the link one), neither of which has the prefix I wanted to fix. Furthermore, in this stage I am not able to access internet (actually, it appears that existing connections keep working while new ones cannot be stablished).

And if I reboot the system (I believe restarting NetworkManager may be enough but am not sure) my wireless adapter is not even able to start (the wlp2s0 interface stays down with no carrier).

Now, to my questions:

1. I know that the proper way to do what I want is with a token, but why exactly does my config does not fix an IP to have my suffix?

2. Why do I get two new addresses, one with noprefixroute and one without, instead of only one?

3. Why rebooting the kernel kills the interface?

I appreciate any insights!