發現增加虛擬介面會使得網路重開帶不起來該介面，所以改採用執行指令的方式
讓他啟動網路卡之後再自己執行指令增加v6位址
auto eth0
iface eth0 inet static
address 192.168.13.1 # ipv4 address
netmask 255.255.255.0
iface eth0 inet6 static
address 2001:db8::1 #ipv6 address no.1
netmask 64
gateway 2001:db8::ffff
post-up /sbin/ifconfig eth0 inet6 add 2001:db8::2 #ipv6 address no.2
