centos 無線網卡配置

centos 無線網卡配置


自己有臺不常用的筆記本，是centos系統，一次不小心按了Fn，結果就沒有網絡了，後來是各種折騰，終於搞定，留個筆記。
1、查看驅動是否還在
$ lspci | grep Network
07:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8188CE 802.11b/g/n WiFi Adapter (rev 01)
如果出現網卡信息，就是驅動正常，配置錯誤

2、查看網卡狀態
$ ifconfig wlan0
wlan0     Link encap:Ethernet  HWaddr 7c:4f:b5:73:b4:be  
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
$ iwconfig wlan0
wlan0     IEEE 802.11bgn  ESSID:off/any  
          Mode:Managed  Access Point: Not-Associated   Tx-Power=20 dBm   
          Retry  long limit:7   RTS thr=2347 B   Fragment thr:off
          Power Management:off
tips 如果Tx-Power = off 需要 開啓無線網卡電源
iwconfig wlan0 txpower on

3、掃描網絡
$ sudo iwlist wlan0 scan
wlan0     Scan completed :
Edited to only show the relevant network
          Cell 04 - Address: 00:16:01:12:E7:5E
                    Channel:6
                    Frequency:2.437 GHz (Channel 6)
                    Quality=64/70  Signal level=-46 dBm  
                    Encryption key:off
                    ESSID:"aprk"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s
                              24 Mb/s; 36 Mb/s; 54 Mb/s
                    Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 48 Mb/s
                    Mode:Master
                    Extra:tsf=00000000b6d6419d
                    Extra: Last beacon: 224ms ago
                    IE: Unknown: 0009666F6F626172776562
                    IE: Unknown: 010882848B962430486C
                    IE: Unknown: 030106
                    IE: Unknown: 2A0102
                    IE: Unknown: 2F0102
                    IE: Unknown: 32040C121860
                    IE: Unknown: DD090010180201F0000000
                    IE: Unknown: DD180050F2020101800003A4000027A4000042435E0062322F00

4、設置網絡
$ sudo iwconfig wlan0 essid "aprk"
查看ssid設置是否成功
wlan0     IEEE 802.11bgn  ESSID:off/any  
          Mode:Managed  Access Point: Not-Associated   Tx-Power=20 dBm   
          Retry  long limit:7   RTS thr=2347 B   Fragment thr:off
          Encryption key:off
          Power Management:off
設置失敗，這個地方反覆出現問題，嘗試添加參數
sudo iwconfig wlan0 key open mode Managed essid "aprk" channel 6
查看ssid設置是否成功
$ sudo iwconfig wlan0 # check to see if settings took hold this time
wlan0     IEEE 802.11bgn  ESSID:"aprk"  
          Mode:Managed  Frequency:2.437 GHz  Access Point: Not-Associated   
          Tx-Power=20 dBm   
          Retry  long limit:7   RTS thr=2347 B   Fragment thr:off
          Encryption key:off
          Power Management:off
network默認支持wep加密，建議先設置無需密碼，以後在重新添加

5、啓用dhcp，獲取ip並連接
$ sudo dhclient -v wlan0  
Internet Systems Consortium DHCP Client 4.1.1-P1
Copyright 2004-2010 Internet Systems Consortium.
All rights reserved.
For info, please visit https://www.isc.org/software/dhcp/


Listening on LPF/wlan0/7c:4f:b5:73:b4:be
Sending on   LPF/wlan0/7c:4f:b5:73:b4:be
Sending on   Socket/fallback
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 3
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 6
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 11
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 17
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 15
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 9
No DHCPOFFERS received.
No working leases in persistent database - sleeping.


6、聯網成功
安裝networkmanager，這個可以有圖形界面，不用在以來命令行折騰
$ sudo yum install NetworkManager NetworkManager-gnome #這裏根據自己的桌面環境自己調整

7、最後
路由器給wifi加上密碼，電腦reboot，之後就會出現網絡設置圖標，搞定！