为啥这两者对应的ip不同？
而www.google.com.tw和www.google.co.jp是同一个ip？

$ ping -c 4 baidu.com
PING baidu.com (220.181.6.184) 56(84) bytes of data.

$ ping -c 4 www.baidu.com
PING www.a.shifen.com (119.75.218.45) 56(84) bytes of data.

$ ping -c 4 www.google.com
PING www-g-com-chn.l.google.com (72.14.203.104) 56(84) bytes of data.

$ ping -c 4 www.google.com.hk
PING www-g-com-hk-chn.l.google.com (72.14.203.106) 56(84) bytes of data.

$ ping -c 4 www.google.com.tw
PING www-g-com-chn.l.google.com (72.14.203.99) 56(84) bytes of data.

$ ping -c 4 www.google.com.jp
ping: unknown host www.google.com.jp

$ ping -c 4 www.google.co.jp
PING www-g-com-chn.l.google.com (72.14.203.99) 56(84) bytes of data.
--
FROM 210.77.2.*