测试能 ping 通的联通 DNS 服务器
123.123.123.123
221.5.203.98
210.21.196.6
202.99.160.68
202.97.224.69
202.98.0.68
202.99.224.68
202.99.192.66
119.6.6.6
221.12.1.227
123.123.123.124
221.7.92.98
221.5.88.88
202.99.166.4
202.97.224.68
202.99.224.8
202.99.192.68
221.12.33.227