No WiFi after upgrade to 15.04

Question

After upgrading to 15.04, wifi doesn't enable an internet connection. The interface connects to the router,however. I saw a similar question, where the solution was to delete two iwlwifi files - tried this w/out success. From lspci:

00:15.0 Network controller [0280]: Ralink corp. RT2500 Wireless 802.11bg [1814:0201] (rev 01)

malcolm@PackbellLaptop:~$ iwconfig
wlan0     IEEE 802.11bg  ESSID:"WLAN-Osborne"  
          Mode:Managed  Frequency:2.437 GHz  Access Point: C0:A0:BB:C2:00:4E   
          Bit Rate=48 Mb/s   Tx-Power=20 dBm   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Power Management:on
          Link Quality=47/70  Signal level=-63 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

lo        no wireless extensions.

eth0      no wireless extensions.

malcolm@PackbellLaptop:~$ uname -a
Linux PackbellLaptop 3.19.0-15-generic #15-Ubuntu SMP Thu Apr 16 23:32:01 UTC 2015 i686 athlon i686 GNU/Linux
malcolm@PackbellLaptop:~$ lspci -nnk | grep -A3 RT2500
00:15.0 Network controller [0280]: Ralink corp. RT2500 Wireless 802.11bg [1814:0201] (rev 01)
    Subsystem: Ralink corp. RT2500 Wireless 802.11bg [1814:2560]
    Kernel driver in use: rt2500pci
00:18.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] K8 [Athlon64/Opteron] HyperTransport Technology Configuration [1022:1100]
00:18.1 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] K8 [Athlon64/Opteron] Address Map [1022:1101]
wlan0     Link encap:Ethernet  HWaddr 00:10:60:63:e0:3c  
          inet6 addr: fe80::210:60ff:fe63:e03c/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:124 errors:0 dropped:0 overruns:0 frame:0
          TX packets:148 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:16911 (16.9 KB)  TX bytes:23073 (23.0 KB)
malcolm@PackbellLaptop:~$ route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.0.0.2        0.0.0.0         UG    1024   0        0 wlan0
10.0.0.0        0.0.0.0         255.255.255.0   U     0      0        0 wlan0
169.254.0.0     0.0.0.0         255.255.0.0     U     1000   0        0 wlan0

Network manager syslog is at paste.ubuntu.com/10981489

Solution 1

With no IP address in ifconfig and no route details, it doesn't appear that you have connected to the router. However, syslog shows that you connect with no obvious and therefore fixable issues, but immediately disconnects.

First, check the settings in the router. WPA2-AES is preferred; not any WPA and WPA2 mixed mode and certainly not TKIP. Second, if your router is capable of N speeds, you may have better connectivity with a channel width of 20 MHz in the 2.4 GHz band instead of automatic 20/40 MHz, although it is likely to affect N speeds. I also have better luck with a fixed channel, either 1, 6 or 11, rather than automatic channel selection. Also, be certain the router is not set to use N speeds only; auto B, G and N is preferred. After making these changes, reboot the router.

Next, I recommend that your regulatory domain be set explicitly. Check yours:

sudo iw reg get

If you get 00, that is a one-size-maybe-fits-all setting. Find yours here: http://en.wikipedia.org/wiki/ISO_3166-1_alpha-2 Then set it temporarily:

sudo iw reg set IS

Of course, substitute your country code if not Iceland. Set it permanently:

gksudo gedit /etc/default/crda

Use nano or kate or leafpad if you don't have the text editor gedit. Change the last line to read:

REGDOMAIN=IS

Proofread carefully, save and close the text editor.

Next, I'd set IPv6 to Ignore in Network Manager: http://docs.fedoraproject.org/en-US/Fedora/18/html/Installation_Guide/images/netconfig/network-connections-ipv6-ignore.png This example is for ethernet, but you want wireless.

Solution 2

Detect and install additional Ubuntu driver with ubuntu-drivers package.

Open a terminal Ctrl+Alt+T and type following:

sudo ubuntu-drivers autoinstall

Comments

[solsTiCe]

output of route -n is empty. Is it an error or the ouput is empty ?

[Malcolm Osborne]

Output of route -n is empty

[gertvdijk]

From the information provided in a comment to an answer it appears that your WiFi adapter is working and connecting to your AP, it's associated and authenticated, but right after that it disconnects again and attempts a new connection, turning into a loop of disconnects/connects. There may be a lot of reasons for that, including plain IP/DHCP connection not working. We will need more broader details to solve this. We can't see your screen and we don't have your hardware here, so...

[gertvdijk]

(continued) it may be a better idea to put all this on a forum which is more suitable for a trial&error approach. This is a Q&A site, not fit for lots of iterations on questions with changing the question over time constantly.

[Malcolm Osborne]

The interface is active, so don't think this line of action will get a solution. No info is output from the dmesg command

[Malcolm Osborne]

Additional AMD64 microcode was installed with this. No solution yet.

[Malcolm Osborne]

ifconfig and route outputs added to question, route just gives the headers

[Salehi]

So, you have to download the corresponding driver source of your Product which should be released by manufacturer.

[Malcolm Osborne]

I have had Ubuntu on this laptop since 10.04 - wifi has always worked, why does it now not work on 15.04?

[gertvdijk]

@MalcolmOsborne Please put that valuable information in your question!

[Salehi]

May be that package of your driver, is not available in the vivid releae of ubuntu. If you don't have the problem with previous versions, you can install old package manually until a newer version became available.

[chili555]

Please see my edit above.

[Malcolm Osborne]

@chili555 - Thank you for your advice. I made changes to the router and to the laptop config, then a stable wifi connection was made and I thought the problem was solved. I get an IP assignment and route setup. However, still no internet access! A ping to 10.0.0.2 is reported by 10.0.0.5 (my device) as Destination Host Unreachable.

[chili555]

What is 10.0.0.2? The router? What does this report now? route -n.

[Malcolm Osborne]

I have added the routing table in the question above, but it doesn't seem to be showing in the correct format. 10.0.0.2 is the router.

[Thomas Ward]

Doing a clean installation is usually overkill for this type of situation.

[Brendan W]

this worked for me!!

[Salehi]

Yeah @brendan , this is really useful ;) Vote this post up if your problem has been solved with it ;)