网络接口配置文件
[root@localhost ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0
# Intel Corporation 82545EM Gigabit Ethernet Controller (Copper)
TYPE=Ethernet       #网卡类型
DEVICE=eth0         #网卡接口名称
ONBOOT=yes          #系统启动时是否自动加载
BOOTPROTO=static    #启用地址协议 --static:静态协议 --bootp协议 --dhcp协议
IPADDR=192.168.1.11      #网卡IP地址
NETMASK=255.255.255.0    #网卡网络地址
GATEWAY=192.168.1.1      #网卡网关地址
DNS1=10.203.104.41       #网卡DNS地址
HWADDR=00:0C:29:13:5D:74 #网卡设备MAC地址
BROADCAST=192.168.1.255  #网卡广播地址 

重新导入ifcfg-eth0网络配置文件
[root@localhost ~]# /etc/init.d/network reload
Shutting down interface eth0:                             [ OK ]
Shutting down loopback interface:                         [ OK ]
Bringing up loopback interface:                           [ OK ]
Bringing up interface eth0:                               [ OK ]

网卡接口关闭与激活
[root@localhost ~]# ifdown eth0   #关闭网络
[root@localhost ~]# ifup eth0     #启动网络

网络服务启动与关闭
方法一:
[root@localhost ~]# service network stop    #关闭网络服务
[root@localhost ~]# service network start   #启动网络服务
[root@localhost ~]# service network restart #重启网络服务
方法二：
[root@localhost ~]# /etc/init.d/network stop
[root@localhost ~]# /etc/init.d/network start
[root@localhost ~]# /etc/init.d/network restart 
网卡状态查询
[root@localhost ~]# service network status
Configured devices:
lo eth0
Currently active devices:
lo eth0

临时配置网卡信息，无需重启。
[root@localhost ~]# ifconfig eth0 10.1.1.10 netmask 255.0.0.0

查看网卡接口信息，默认列出所有接口
[root@localhost ~]# ifconfig
eth0      Link encap:Ethernet  HWaddr 00:0C:29:13:5D:74
          inet addr:192.168.1.11  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::20c:29ff:fe13:5d74/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:413 errors:0 dropped:0 overruns:0 frame:0
          TX packets:572 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:47701 (46.5 KiB)  TX bytes:64842 (63.3 KiB)
          Base address:0x2000 Memory:d8920000-d8940000 

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:407 errors:0 dropped:0 overruns:0 frame:0
          TX packets:407 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:70759 (69.1 KiB)  TX bytes:70759 (69.1 KiB)

查看当前路由及网关信息
[root@localhost ~]# netstat -r
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
192.168.1.0     *               255.255.255.0   U         0 0          0 eth0
169.254.0.0     *               255.255.0.0     U         0 0          0 eth0
default         192.168.1.1     0.0.0.0         UG        0 0          0 eth0

DNS：
主机名：CentOS
主DNS：202.106.46.151
第二DNS:202.106.0.20
第三DNS:8.8.8.8

网络配置：
eth0
静态ip：192.168.1.106
子网掩码??????? 255.255.255.0
默认网关 IP???? 192.168.1.1


DEVICE=eth0
IPADDR=192.168.1.106
NETMASK=255.255.255.0
BROADCAST=192.168.1.255
ONBOOT=yes
BOOTPROTO=none
GATEWAY=192.168.1.1
TYPE=Ethernet
"/etc/sysconfig/network-scripts/ifcfg-eth0" 11L, 187C