问题现象：
[root@decode from_jackzhang]# ping www.baidu.com ping: unknown host www.baidu.com
分析问题：
dns没有配置
解决问题：
配置dns为:8.8.8.8
[root@decode from_jackzhang]# setup [root@decode from_jackzhang]# ping www.baidu.com PING www.a.shifen.com (119.75.217.109) 56(84) bytes of data. 64 bytes from 119.75.217.109: icmp_seq=1 ttl=54 time=31.7 ms 64 bytes from 119.75.217.109: icmp_seq=2 ttl=54 time=32.1 ms 64 bytes from 119.75.217.109: icmp_seq=3 ttl=54 time=31.5 ms ^C --- www.a.shifen.com ping statistics --- 3 packets transmitted, 3 received, 0% packet loss, time 2718ms rtt min/avg/max/mdev = 31.556/31.839/32.166/0.290 ms [root@decode from_jackzhang]#