The new power management features enabled in the Intel Centrino Wireless-N 2200 Wifi Card aren’t supported as of Linux Kernel 3.4.0-030400-generic. In 802.11n mode, this wifi card will sometimes drop down to 1 Mbps and stop receiving data altogether.
Symptoms
- Run lspci -v and make sure that your wireless network controller has iwlwifi listed next to Kernel driver in use.
- Network packets are lost and iwconfig shows current network speed as 1Mbps.
To fix this, you can either turn off power management or disable 802.11n on the wireless card.
Option 1: Turn off power management
1. Run the following command, where wlan0 is the identifier for your wireless card.
# iwconfig wlan0 power off
2. Make sure that wireless connectivity is restored. To make this change permanent, open up the following file:
/usr/lib/pm-utils/power.d/wireless
Edit line 39 to say iwconfig_batt=”poweroff” instead of iwconfig_batt=”poweron”.
3. Reboot to see changes.
Option 2: Turn off 802.11n
This will keep power management enabled, but it will limit your wifi speed and range to 802.11g speeds.
1. Run the following commands
# rmmod iwlwifi
# modprobe iwlwifi 11n_disable=1
2. Make sure that wireless connectivity is restored. To make this change permanent, create a new file in /etc/modprobe.d and put the following in it:
options iwlwifi 11n_disable=1
3. Reboot to see changes.