The token command explicitly configures the lower 64 bits that will be used with any autoconf
address, as opposed to one derived from the macaddr. This aligns the autoconf-assigned address with
the fixed one set above, and can do so as a pre-up command to avoid ever having another address
even temporarily, when this is all set up before boot.
https://man7.org/linux/man-pages/man8/ip-token.8.html
```
sudo sysctl -w net.ipv6.conf.all.forwarding=0
sudo ip token set ::192:0:2:1 dev eth1
sudo sysctl -w net.ipv6.conf.all.forwarding=1
```
List tokens:
```
vyos@r14# sudo ip token list
token :: dev eth0
token ::192:0:2:1 dev eth1
[edit]
vyos@r14#
```
Expecting DHCPv6 address with configured host address, something like:
```
set interfaces ethernet eth1 address dhcpv6
2001:db8:23:192:0:2:1/64
```
So it doesn't depend on which network we get, host part perhaps will be the same eve if we change the NIC