After upgrading from 11.04 to 12.04, Wireless works intermidantly...

[varunendra]

[B]I don't know why overwriting two files you said were the wrong ones would cause it to work better unless it reset some kind of glitch.

Umm.. a bit confusing to me also but the result of:

modinfo carl9170

clearly shows that it uses only carl9170-1.fw firmware.

Since that firmware also pre-exists in the /lib/firmware directory, I think it's just a matter of chance that it got connected.

I guess it's time to search for a command to figure out the firmware in use

[TMundo]

looks like it finally went back to it's old behavior, it took some bit of time, but it eventually did. I will try the next step you posted and let you know what happens.

[varunendra]

If you wish to try post #9, then in order to make the nohwcrypt=1 parameter permanent, do this:

echo "options carl9170 nohwcrypt=1" | sudo tee /etc/modprobe.d/carl9170.conf

If it doesn't seem to help, you can simply delete the /etc/modprobe.d/carl9170.conf file, or just comment out the line by adding a # in its beginning :

# options carl9170 nohwcrypt=1

[TMundo]

Okay:

I downloaded the carl9170 and installed it following your directions. It is still giving some intermittant trouble but seems to work much longer. It always seems to work long after I reset the computer, so I'm not sure if the firmware made it operate a bit longer or or not. It's hard to tell how much time I'll get out of it before it malfunctions, but I gues the point is, it still malfunctions eventually. As per your instructions, here is the output to the codes: (when it is working)

iwconfig iwlist scan

iwconfig

lo        no wireless extensions.

wlan0     IEEE 802.11bgn  ESSID:"TMundo"  
          Mode:Managed  Frequency:2.437 GHz  Access Point: 98:FC:11:90:59:C0   
          Bit Rate=19.5 Mb/s   Tx-Power=20 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=47/70  Signal level=-63 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:13812  Invalid misc:806   Missed beacon:0

eth0      no wireless extensions.

tmundo@tmundo-Precision-WorkStation-390:~$ iwlist scan
lo        Interface doesn't support scanning.

wlan0     Scan completed :
          Cell 01 - Address: 98:FC:11:90:59:C0
                    Channel:6
                    Frequency:2.437 GHz (Channel 6)
                    Quality=48/70  Signal level=-62 dBm  
                    Encryption key:on
                    ESSID:"TMundo"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s
                              24 Mb/s; 36 Mb/s; 54 Mb/s
                    Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 48 Mb/s
                    Mode:Master
                    Extra:tsf=000001af41036183
                    Extra: Last beacon: 83752ms ago
                    IE: Unknown: 0006544D756E646F
                    IE: Unknown: 010882848B962430486C
                    IE: Unknown: 030106
                    IE: Unknown: 2A0100
                    IE: Unknown: 2F0100
                    IE: IEEE 802.11i/WPA2 Version 1
                        Group Cipher : TKIP
                        Pairwise Ciphers (2) : CCMP TKIP
                        Authentication Suites (1) : PSK
                    IE: Unknown: 32040C121860
                    IE: Unknown: 2D1AFC181BFFFF000000000000000000000000000000000000000000
                    IE: Unknown: 3D1606080000000000000000000000000000000000000000
                    IE: Unknown: 4A0E14000A002C01C800140005001900
                    IE: Unknown: 7F0101
                    IE: Unknown: DD700050F204104A00011010440001021041000100103B000103104700108B16DAE3AD888310C63399C4B4965314102100074C696E6B737973102300054531303030102400063132333435361042000234321054000800060050F2040001101100054531303030100800020084103C000101
                    IE: Unknown: DD090010180200F0040000
                    IE: WPA Version 1
                        Group Cipher : TKIP
                        Pairwise Ciphers (2) : CCMP TKIP
                        Authentication Suites (1) : PSK
                    IE: Unknown: DD180050F2020101000003A4000027A4000042435E0062322F00

eth0      Interface doesn't support scanning.

I will wait until it stops working to post the rest of the code response you gave me.

Which is, (for anyone else who is reading this

dmesg | grep -e wlan -e carl9170

[varunendra]

Hmm.. here's my latest finding : http://ubuntuforums.org/showpost.php?p=12305169

Accordingly, I think you should try 12.10 using a live cd/usb and test it for stability of wifi (+ other things). If it really proves to be as stable as the post states, consider doing a fresh install of 12.10 on your system (to avoid carrying any misconfiguration from the current setup).

Apart from above, two other things come to mind which you can try beforehand.

1) Since you are not using high speeds anyway, try disabling the n-channel in your router.

2) Try disabling IPv6 by adding the following lines to your /etc/sysctl.conf file :

# force-disable IPv6
net.ipv6.conf.all.disable_ipv6=1
net.ipv6.conf.default.disable_ipv6=1
net.ipv6.conf.lo.disable_ipv6=1

To do it quickly, you can just copy-paste the following command in terminal:

echo -e "\n# force-disable IPv6\nnet.ipv6.conf.all.disable_ipv6=1\nnet.ipv6.conf.default.disable_ipv6=1\nnet.ipv6.conf.lo.disable_ipv6=1" | sudo tee -a /etc/sysctl.conf

Reboot and check the connection stability.

If neither these nor the new 12.10 solve the problem, then I guess it's time to honour the warning I quoted earlier in post#9, and get a better supported card

Fingers crossed, awaiting the result of this 'last' shot..

[TMundo]

hmmm, I haven't tried the latest instructions yet, because I was waiting for the connectivity to stop. so I could give you the results of

dmesg | grep -e wlan -e carl9170

want to give you as much info as possible.

However, connectivity did not stop for the next three days. I was waiting with the command pasted in the terminal so I could run it as soon as connectivity stopped, but after a day or so I must have closed it. I'm sure I reset the computer at some point as well. Anyway. This time I will keep the code more handy.

As for the:

echo -e "\n# force-disable IPv6\nnet.ipv6.conf.all.disable_ipv6=1\nnet.ipv6.conf.default.disable_ipv6=1\nnet.ipv6.conf.lo.disable_ipv6=1" | sudo tee -a /etc/sysctl.conf

I would like to give you the info from the other code first (when connectivity stops) unless of course one issue has nothing to do with the other. Should this not work, is there any way to reverse it? (should it not connect at all.)

Also, now that the carl9170.fw is installed, even though it is not permanent, does that mean... well, what does 'not-permanent' mean exactly? It doesn't go back to the original settings after a reset, does it?

[TMundo]

Okay, the plot thickens

When connectivity stopped, I entered:

dmesg | grep -e wlan -e carl9170

and the output was:

[   21.994656] usbcore: registered new interface driver carl9170  
 [   22.645723] Registered led device: carl9170-phy0::tx  
 [   23.152869] ADDRCONF(NETDEV_UP): wlan0: link is not ready  
 [   23.153580] ADDRCONF(NETDEV_UP): wlan0: link is not ready  
 [   26.589535] wlan0: authenticate with 98:fc:11:90:59:c0 (try 1)  
 [   26.591291] wlan0: authenticated  
 [   26.718793] wlan0: associate with 98:fc:11:90:59:c0 (try 1)  
 [   26.722946] wlan0: RX AssocResp from 98:fc:11:90:59:c0 (capab=0x411 status=0 aid=1)  
 [   26.722954] wlan0: associated  
 [   26.826977] ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready  
 [   37.952025] wlan0: no IPv6 routers present

Also, it must be noted, and this is very strange, after I had finished copying and pasting the code into Libre Office, and prepared to reboot the computer or unplug the card, I went and refreshed one of the pages that wouldn't load when connectivity halted, and voila, all of a sudden connectivity was working again. I don't know if and when connectivity stops, whether it is only for a few minutes, or whether it is for much longer, because in the past, I never really went to do another task on the computer when connectivity would stop, I would simply pull the card out and then plug it back in. Don't know if this gives us any more useful info.


-TMundo

[Bucky Ball]

Run the code to switch of IPv6. Set to 'Ignore' in Network Manager also.

[varunendra]

Should this not work, is there any way to reverse it? (should it not connect at all.)

Yes, we always can revert the changes we make. That said, IPv6 is still used very rarely, so it is okay (or sometimes even better) to leave it disabled (of-course unless it is the one that is being used for connection in your router - which is, as I said, still a very rare case).

Also, now that the carl9170.fw is installed, even though it is not permanent, does that mean... well, what does 'not-permanent' mean exactly? It doesn't go back to the original settings after a reset, does it?

'Temporary' is the parameter (nohwcrypt=1) that you are using with the carl9170 module, not the firmware file (carl9170.fw). It is just a file which is there now, and is permanent unless you (or an update) replace it with the backup or a new one. Also, even the parameter is permanent if you have put it in the '.conf' file as I wrote earlier. But making that parameter permanent is of no use (or may even be harmful) if it is not helping the stability.

Also, it must be noted, and this is very strange, after I had finished copying and pasting the code into Libre Office, and prepared to reboot the computer or unplug the card, I went and refreshed one of the pages that wouldn't load when connectivity halted, and voila, all of a sudden connectivity was working again.

^That behaviour can be (not necessarily though) caused by unnecessary IPv6 requests while the actual connection is IPv4-only. Accordingly, please try what Bucky Ball suggested above (that is- disable IPv6 as I suggested, then also set it to 'Ignore' in NM).

[TMundo]

okay, executed that command, and switched the setting to ignore, will see what happens, thanks guys!