Connecting wifi in CLI mode

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When i was work as sysadmin command line interface is a big friend, i always use command line in my live every day. I didn't feel heavy while using it. For the example, when i want to connecting my notebook to the wifi. Ofcourse unix/linux has so much tool for handling wireless connection which is run over GUI. But, connecting wifi using command line was more fun. Did you not believe? I will show you the tips.

It just for fun connecting notebook to wifi using command line interface. First of all, your wireless interface must be detected by your kernel. Unless, you must configure your wireless driver, for this issue see my article: "Howto configure ndiswrapper for broadcom driver in linux slackware".

Check your available network interface as shown bellow:

 # ifconfig -a
 eth0 Link encap:Ethernet HWaddr 54:04:A6:79:25:DB
     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)
     Interrupt:44 Base address:0x2000

 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:24 errors:0 dropped:0 overruns:0 frame:0
     TX packets:24 errors:0 dropped:0 overruns:0 carrier:0
     collisions:0 txqueuelen:0
     RX bytes:1360 (1.3 Kb) TX bytes:1360 (1.3 Kb)

 wlan0 Link encap:Ethernet HWaddr 78:92:9C:20:F5:DC
     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)

You can check your network interfaces, is there any wireless extension in your interfaces:

 # iwconfig
 lo no wireless extensions.

 eth0 no wireless extensions.

 wlan0 IEEE 802.11bgn ESSID:off/any
 Mode:Managed Access Point: Not-Associated Tx-Power=14 dBm
 Retry long limit:7 RTS thr:off Fragment thr:off
 Encryption key:off
 Power Management:off

Checking availability wireless network.

 # iwlist wlan0 scanning
 wlan0 Scan completed :
 Cell 01 - Address: 04:18:0F:DB:1D:D0
     Channel:3
     Frequency:2.422 GHz (Channel 3)
     Quality=70/70 Signal level=-39 dBm
     Encryption key:on
     ESSID:"AndroidTether"
     Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 6 Mb/s; 9 Mb/s
     11 Mb/s; 12 Mb/s; 18 Mb/s
     Bit Rates:24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s
     Mode:Master
     Extra:tsf=0000000014d7f180
     Extra: Last beacon: 402ms ago
    IE: Unknown: 000D416E64726F6964546574686572
     IE: Unknown: 010882848B0C12961824
     IE: Unknown: 030103
     IE: Unknown: 0706555320010B1B
     IE: Unknown: 2A0100
     IE: Unknown: 32043048606C
     IE: IEEE 802.11i/WPA2 Version 1
     Group Cipher : CCMP
     Pairwise Ciphers (1) : CCMP
     Authentication Suites (1) : PSK
 Cell 02 - Address: 00:1D:7E:58:F9:C7
     Channel:11
     Frequency:2.462 GHz (Channel 11)
     Quality=43/70 Signal level=-67 dBm
     Encryption key:on
     ESSID:"KambingNet"
     Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s
     12 Mb/s; 24 Mb/s; 36 Mb/s
     Bit Rates:9 Mb/s; 18 Mb/s; 48 Mb/s; 54 Mb/s
     Mode:Master
     Extra:tsf=00000096f15cb83e
     Extra: Last beacon: 304ms ago
     IE: Unknown: 000A4B616D62696E674E6574
     IE: Unknown: 010882848B960C183048
     IE: Unknown: 03010B
     IE: Unknown: 0706444520010D14
     IE: Unknown: 2A0100
     IE: Unknown: 32041224606C
     IE: Unknown: 080A0001BD1E79228A000000

We will use AndroidTether as our wireless network. So, we must define the essid and password using tool wpa_passphrase bellow:

essid : AndroidTheter
password: abcdefghijklm

# wpa_passphrase AndroidTheter abcdefghijklm >> /etc/wpa_supplicant.conf

This command updates /etc/wpa_supplicant.conf with following contens as follow:

 network={
     ssid="AndroidTheter"
     #psk="abcdefghijklm"
     psk=27847e70acd62edc138c4c859ef5df9ff21708bb7c5d8b033cca60951ca7ba10
 }

Then, we can start to lunch wireless adapter to request access to the network.

# wpa_supplicant -D wext -c /etc/wpa_supplicant.conf -i wlan0 -B
 root@darkstar:~# dhclient wlan0

 root@darkstar:~# ifconfig wlan0
 wlan0 Link encap:Ethernet HWaddr 78:92:9C:20:F5:DC
 inet addr:192.168.2.103 Bcast:192.168.2.255 Mask:255.255.255.0
 inet6 addr: fe80::7a92:9cff:fe20:f5dc/64 Scope:Link
 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
 RX packets:5 errors:0 dropped:0 overruns:0 frame:0
 TX packets:42 errors:0 dropped:0 overruns:0 carrier:0
 collisions:0 txqueuelen:1000
 RX bytes:1008 (1008.0 b) TX bytes:6295 (6.1 Kb)

Ip address was gotten, so gateway and dns server would be obtained also.

root@darkstar:~# route -n
 Kernel IP routing table
 Destination Gateway Genmask Flags Metric Ref Use Iface
 192.168.2.0 0.0.0.0 255.255.255.0 U 0 0 0 wlan0
 127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
 0.0.0.0 192.168.2.254 0.0.0.0 UG 0 0 0 wlan0

 # cat /etc/resolv.conf
 nameserver 192.168.2.254

 # ping binksh.blogspot.com
 PING blogspot.l.google.com (209.85.175.132) 56(84) bytes of data.
 64 bytes from nx-in-f132.1e100.net (209.85.175.132): icmp_req=1 ttl=39 time=218 ms
 64 bytes from nx-in-f132.1e100.net (209.85.175.132): icmp_req=2 ttl=39 time=157 ms
 64 bytes from nx-in-f132.1e100.net (209.85.175.132): icmp_req=3 ttl=39 time=157 ms
 ^C
 --- blogspot.l.google.com ping statistics ---
 3 packets transmitted, 3 received, 0% packet loss, time 2001ms
 rtt min/avg/max/mdev = 157.045/177.675/218.392/28.792 ms