linux下ifconfig、iwconfig、iwlist命令详解

 在linux下查看网络信息。

一、ifconfig

     用途：配置网络信息。

     如果没有参数，将给出当前的active 接口。

# ifconfig
eth0      Link encap:Ethernet  HWaddr 02:00:E1:00:11:5A  
          inet addr:192.168.1.234  Bcast:192.168.1.255  Mask:255.255.254.0
          inet6 addr: fe80::e1ff:fe00:115a/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:17338002 errors:0 dropped:11993 overruns:0 frame:0
          TX packets:228594 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1759095713 (1.6 GiB)  TX bytes:67780580 (64.6 MiB)
          Interrupt:33 Base address:0xc000 

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:65536  Metric:1
          RX packets:43362 errors:0 dropped:0 overruns:0 frame:0
          TX packets:43362 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:4835488 (4.6 MiB)  TX bytes:4835488 (4.6 MiB)

wlan0     Link encap:Ethernet  HWaddr CC:79:CF:E2:FB:91  
          inet addr:192.168.50.180  Bcast:192.168.50.255  Mask:255.255.255.0
          inet6 addr: fe80::ce79:cfff:fee2:fb91/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:460463 errors:0 dropped:26240 overruns:0 frame:0
          TX packets:276794 errors:0 dropped:4 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:159088799 (151.7 MiB)  TX bytes:83207394 (79.3 MiB)

这是开发板上的一块物理网卡和一个wifi模块。我们可以看到IP信息，网卡地址等等。这个命令还常用来设置网络信息

其中lo地址是127.0.0.1，这个地址是一个回环地址，代表本机（localhost）。

eg：ifconfig eth0 192.168.1.100. 设置IP

有文档描述此命令即将废除，取代这个命令的是ip addr和ip link。 可以试试 ip -s link。

二、iwconfig

用途：配置无线网络接口

iwconfig [interface]

iwconfig interface [essid X] [nwid N] [modeM] [freq F]

[channel C][sens S ][ap A ][nick NN ]

[rate R] [rts RT] [frag FT] [txpower T]

[enc E] [key K] [power P] [retry R]

[modu M] [commit]

描述：iwconfig和ifconfig很相似。但是iwconfig仅仅和无线网络相关。用来设置参数等。

freq/channel
eg:
iwconfig eth0 freq 2422000000
iwconfig eth0 freq 2.422G
iwconfig eth0 channel 3
iwconfig eth0 channel auto

三、iwlist

iwlist：从无线网卡获取更详细的无线信息

描述：用于显示关于无线网络的额外信息。这些信息往往是iwconfig没有显示出来的。

scan：给出可以接入的热点列表信息。

rate/bit: 列出设备支持的比特率

相关文件： /proc/net/wireless

Usage: iwlist [interface] scanning [essid NNN] [last]
              [interface] frequency 
              [interface] channel 
              [interface] bitrate 
              [interface] rate 
              [interface] encryption 
              [interface] keys 
              [interface] power 
              [interface] txpower 
              [interface] retry 
              [interface] ap 
              [interface] accesspoints 
              [interface] peers 
              [interface] event 
              [interface] auth 
              [interface] wpakeys 
              [interface] genie 
              [interface] modulation 

# iwlist wlan0 frequency
wlan0     13 channels in total; available frequencies :
          Channel 01 : 2.412 GHz
          Channel 02 : 2.417 GHz
          Channel 03 : 2.422 GHz
          Channel 04 : 2.427 GHz
          Channel 05 : 2.432 GHz
          Channel 06 : 2.437 GHz
          Channel 07 : 2.442 GHz
          Channel 08 : 2.447 GHz
          Channel 09 : 2.452 GHz
          Channel 10 : 2.457 GHz
          Channel 11 : 2.462 GHz
          Channel 12 : 2.467 GHz
          Channel 13 : 2.472 GHz
          Current Frequency:2.457 GHz (Channel 10)

# iwlist wlan0 channel
wlan0     13 channels in total; available frequencies :
          Channel 01 : 2.412 GHz
          Channel 02 : 2.417 GHz
          Channel 03 : 2.422 GHz
          Channel 04 : 2.427 GHz
          Channel 05 : 2.432 GHz
          Channel 06 : 2.437 GHz
          Channel 07 : 2.442 GHz
          Channel 08 : 2.447 GHz
          Channel 09 : 2.452 GHz
          Channel 10 : 2.457 GHz
          Channel 11 : 2.462 GHz
          Channel 12 : 2.467 GHz
          Channel 13 : 2.472 GHz
          Current Frequency:2.457 GHz (Channel 10)