Ubuntu Wireless network connection in command line

After installed the the graphical card driver in Ubuntu, the GNOME desktop is not working anymore, needs to install and s Etup the Wireless network command line, herewith the procedure,

1, scan the available WiFi network,

sudo iwlist scan

2, receive the WiFi network password

Wpa_passphrase Yourssid Yourwifipassword

The result is similar as:

Network={ssid= "Yourssid" #psk = "Yourwifipassword" Psk=fe727aa8b64ac9b3f54c72432da14faed933ea511ecab1 5BBC6C52E7522F709A}

3, edit the/etc/network/interfaces

sudo vim/etc/network/interfaces

My configuration is as:

Auto Wlan0allow-hotplug wlan0       gateway 192.168.2.1       WPA-PSK "The password PSK just generated"       wpa-ssid " Yourssid "

4, restart the network and Wlan0

sudo/etc/init.d/networking restart

sudo ifdown wlan0sudo ifup wlan0

5, problem encountered, Canno access the external network

Ping 8.8.8.8 failed,

Ping www.google.com failed.

Ping the local area network successful,

Found the network go through the Wired interface eth0, deleted the eth0 configuration in The/etc/network/interfaces, then Restart the network service and wlan0, problem resolved.

Ubuntu Wireless network connection in command line