Instead of using a self made function like https://github.com/vyos/vyos-1x/blob/e416035c66fe8f8bcb0dfce8058deff10656075c/python/vyos/ifconfig/tunnel.py#L165-L187
evaluate if we can switch to addrgenmode https://patchwork.ozlabs.org/project/netdev/patch/[email protected]/