Wifi doesn't work on Ubuntu 14.04 anymore!
I've been struggling with my wifi for a week now. Since we changed router and provider(O2 box 6431), the connection doesn't work on Ubuntu anymore, yet it does work on windows (and also on ubuntu with other connections). The crazy thing is that it sometimes randomly works and then just stop after sleep mode and doesn't recover. One of my last attempts was to install another firmware
sudo apt-get install linux-firmware-nonfree
sudo apt-get purge bcmwl-kernel-source broadcom-sta-common broadcom-sta-source && sudo apt-get install b43-fwcutter firmware-b43-installer
but now it fails connect to the router, while before I was connected but had internet didn't work. I add further information here:
mario@ThinkPadMG:~$ ifconfig
eth0 Link encap:Ethernet HWaddr 3c:97:0e:66:d5:a9
inet addr:192.168.1.26 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::3e97:eff:fe66:d5a9/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2779028 errors:0 dropped:0 overruns:0 frame:0
TX packets:1396404 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:4100463259 (4.1 GB) TX bytes:105833025 (105.8 MB)
Interrupt:20 Memory:f3a00000-f3a20000
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:7830 errors:0 dropped:0 overruns:0 frame:0
TX packets:7830 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:667794 (667.7 KB) TX bytes:667794 (667.7 KB)
wlan0 Link encap:Ethernet HWaddr 6c:88:14:f0:6a:28
inet6 addr: fe80::6e88:14ff:fef0:6a28/64 Scope:Link
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:50 errors:0 dropped:0 overruns:0 frame:0
TX packets:50 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:6750 (6.7 KB) TX bytes:7750 (7.7 KB)
mario@ThinkPadMG:~$ iwconfig
wwan0 no wireless extensions.
eth0 no wireless extensions.
lo no wireless extensions.
wlan0 IEEE 802.11abgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=15 dBm
Retry long limit:7 RTS thr:off Fragment thr:off
Power Management:off
mario@ThinkPadMG:~$ route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 1 0 0 eth0
mario@ThinkPadMG:~$ nmcli nm
RUNNING STATE WIFI-HARDWARE WIFI WWAN-HARDWARE WWAN
running connected enabled enabled enabled enabled
mario@ThinkPadMG:~$ lspci -nn | grep 0280
03:00.0 Network controller [0280]: Intel Corporation Centrino Advanced-N 6205 [Taylor Peak] [8086:0085] (rev 34)
Please help!!
[Update] paste.ubuntu.com/9912617
dmesg | grep iwl gives no output
[Update2] I used the command echo "options iwlwifi bt_coex_active=N" | sudo tee -a /etc/modprobe.d/iwlwifi.conf and wifi was ok: I was on Mozilla, watched a video, did stuff and it worked. Then I didn't use my laptop for 10 minutes and now it only shows it's connected to the router, but no actual connection.
Using the command again, connection is back.
This is the result of dmesg | grep -e iwl -e wlan0 : http://paste.ubuntu.com/9921077/
Wireless diagnostic script output: http://paste.ubuntu.com/9912617/
I wonder if the router might be wireless n only, if so the next command and a reboot should fix echo "options iwlwifi 11n_disable=8" | sudo tee -a /etc/modprobe.d/iwlwifi.conf
disable IPv6 in network manager by selecting ignore and add the terminal results for dmesg | grep iwl
then add another change to the module
echo "options iwlwifi bt_coex_active=N" | sudo tee -a /etc/modprobe.d/iwlwifi.conf
Reboot with ethernet cable unplugged
I think your Laptop switches off WI-FI to save power, when its idle.
You can try disabling "Switch off wifi" option in Power Saving Mode, if its a Dell Laptop.