OVH旗下soyoustart的ARM存储服务器非常优惠，仅5欧元/月就有一台2TB的ARM服务器；

但是由于目前不支持IPV6，于是启用UFW防火墙的时候会报错：

root@HXS-Server:~# uname -a
Linux HXS-Server 4.5.2-armada375 #1 SMP Tue Oct 25 11:52:56 CEST 2016 armv7l armv7l armv7l GNU/Linux

root@HXS-Server:~# ufw enable
Command may disrupt existing ssh connections. Proceed with operation (y|n)? y
ERROR: problem running ufw-init
ip6tables-restore: line 4 failed
ip6tables-restore: line 138 failed
ip6tables-restore: line 38 failed

Problem running '/etc/ufw/before6.rules'
Problem running '/etc/ufw/user6.rules'

因此需要停用UFW的IPV6功能：

Open /etc/default/ufw

Disable Unsupported IPV6

Change IPV6=Yes to IPV6=no