CentOS ping: unknown host 解决方法

野性酷女 2022-08-25 05:15 173阅读 0赞

转载自 ：[http://blog.sina.com.cn/s/blog\_8cf0057a0101a1ed.html][http_blog.sina.com.cn_s_blog_8cf0057a0101a1ed.html]

## CentOS  ping: unknown  host 解决方法 ##

(2012-12-25 10:59:55)

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如果某台Linux(CentOS)服务器ping域名, 如下提示:  
\# ping www.sina.com  
ping: unknown host www.sina.com  
  
确认网络没问题的情况下, 可以通过如下步骤寻找解决办法:  
1) 确认设置了域名服务器  
  
       \# cat /etc/resolv.conf  
       nameserver 8.8.8.8       \#（Google的公共DNS服务）  
       nameserver 8.8.4.4       \#（Google的公共DNS服务）  
  
2) 确认网关已设置/确认路由表正常  
  
       \# netstat -rn  
       Kernel IP routing table  
       Destination Gateway Genmask Flags MSS Window irtt Iface  
       0.0.0.0 10.10.10.1 0.0.0.0 UG 0 0 0 eth0  
  
     如果未设置, 则通过如下方式增加网关:  
     \# route add default gw 10.245.75.1  
  
     \# grep GATEWAY /etc/sysconfig/network-scripts/ifcfg\*  
     /etc/sysconfig/network-scripts/ifcfg-eth0:GATEWAY=10.245.75.1  
  
3) 确认可用dns解析  
  
     \# grep hosts /etc/nsswitch.conf  
     hosts:           files dns  
  
  
以上的1) 2) 3) 点只是确认问题，个人喜欢手工编写配置文件，一次解决问题。  
     配置/etc/sysconfig/network-scripts/ifcfg-eth0文件后，重启network服务:  
     vim /etc/sysconfig/network-scripts/ifcfg-eth0  
     DEVICE="eth0"  
     NM\_CONTROLLED="yes"  
     ONBOOT=yes  
     TYPE=Ethernet  
     BOOTPROTO=static  
     IPADDR=10.245.75.240  
     \#PREFIX=24  
     GATEWAY=10.245.75.1  
     DNS1=8.8.8.8  
     DNS2=8.8.4.4  
     DEFROUTE=yes  
     IPV4\_FAILURE\_FATAL=yes  
     IPV6INIT=yes  
     NAME="System eth0"  
     UUID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx \# uuid  
     HWADDR=xx:xx:xx:xx:xx:xx                                   \# hwaddr  
     NETWORKING=yes  
  
     \# service network restart

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