Wifi dropouts in live install - network security password not saved

[theodorn]

Hello,

I'm running a live install Kubuntu 16.04. I'm contemplating adding it as extra Ubuntu for experimenting, have a dual-boot system, Windows 10 on a 256 GB SSD, and Ubuntu Mate 16.04 on a 1 TB HDD. If the Kubuntu will be installed, it will be on the HDD. Otherwise, my system is Intel i7-2600 3.40GHz, 8GB RAM, and motherboard ASRock Z68 Pro3 Gen3. My Wifi card, probably what's most important in regards to my problem, is NetGear, Inc. WNA3100M(v1) Wireless-N 300 [Realtek RTL8192CU], according to the output of lsusb.

As the heading says, my wifi drops out, although Network Manager reports I have Internet connection, just after a few minutes. If I disconnect and connect again, it works fine, for a few minutes, again. The strange thing is, I have to enter the network security key, everytime I disconnect and connect again. In settings, there is a checkmark at Automatically connect to this network when it is available. If I edit the network settings, and try to save the security key, it is still not saved.

Recently, I installed the updates that were available, about 240 MB. It didn't fix this issue, but I think the sessions last a little longer than before, not sure though.

I know this has been reported as a bug. Some users have reported it affects full installations, as well as live installs. Has this bug been fixed in 16.04? Has it been fixed in 16.10?

[GreyGeek]

My previous laptop, an Acer 7739, had the identical wifi chip and experienced the same dropouts while I was running 14.04. It started in the spring of 2015 and forced me to connect to my router, which is less than 3 feet away, with a short piece of cat5 eth cable. In March of this year I installed 16.04 and experienced the same problems with the chip as I did with 14.04. However, 16.04 is a systemd system and I used systemctl restart networkworking.service, (or maybe it was NetworkManager.servvice, I don't remember which) and it would remain stable for the rest of the day. A couple of weeks ago I got my gaming machine back from my grandson and installed KDE Neon User Edition. It has a different wifi chip, AR9462, and is rock sold.

But, you have a definite problem and it may take an update to fix it. When it will come down the pipe I do not know. The more detailed the bug reports the more quickly a solution can be found.
Modinfo rtl8192cu reveals:

:~$ modinfo rtl8192cu
filename:       /lib/modules/4.4.0-45-generic/kernel/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/rtl8192cu.ko
firmware:       rtlwifi/rtl8192cufw_TMSC.bin
firmware:       rtlwifi/rtl8192cufw_B.bin
firmware:       rtlwifi/rtl8192cufw_A.bin
firmware:       rtlwifi/rtl8192cufw.bin
description:    Realtek 8192C/8188C 802.11n USB wireless
license:        GPL
author:         Larry Finger    <Larry.Finger@lwfinger.net>
author:         Ziv Huang       <ziv_huang@realtek.com>
author:         Georgia         <georgia@realtek.com>
srcversion:     2C9D776AE1B25BDC5405217
alias:          usb:v7392p7822d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v2357p0100d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v20F4p624Dd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v2019pAB2Bd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v2001p330Dd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v2001p330Ad*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v2001p3309d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v2001p3307d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0E66p0019d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0DF6p0061d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp8186d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0B05p17ABd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0846pF001d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0846p9021d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v07B8p8178d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v07AAp0056d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0586p341Fd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v050Dp2103d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v050Dp2102d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v050Dp1004d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v2019p1201d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v04F2pAFFCd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v04F2pAFFBd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v04F2pAFF8d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v04F2pAFFAd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v04F2pAFF9d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v04F2pAFF7d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp317Fd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v9846p9041d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v4855p0091d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v4855p0090d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v13D3p3359d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v13D3p3358d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v7392p7811d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v20F4p648Bd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v2019pED17d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v2019pAB2Ed*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v2019pAB2Ad*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v2019p4902d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v2001p3308d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v13D3p3357d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v103Cp1629d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v4856p0091d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0EB0p9071d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0DF6p0077d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0DF6p0070d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0DF6p005Cd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0DF6p0052d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp5088d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0B05p17BAd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0846p9043d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0846p9041d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v07B8p8189d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v07B8p8188d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v06F8pE033d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v050Dp11F2d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v050Dp1102d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp817Cd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp8178d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp8754d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp819Ad*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp818Ad*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp817Fd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp817Ed*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp817Dd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp817Bd*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp817Ad*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp8177d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp8176d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp8170d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp018Ad*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v0BDAp8191d*dc*dsc*dp*ic*isc*ip*in*
depends:        mac80211,rtlwifi,rtl8192c-common,rtl_usb
intree:         Y
vermagic:       4.4.0-45-generic SMP mod_unload modversions 
parm:           swenc:Set to 1 for software crypto (default 0)
 (bool)
parm:           debug:Set debug level (0-5) (default 0) (int)

Your chip has only two parm's. You can set the debug parm to 5 to get better bug reports.
Create a file, say rtl8192cu.conf, in /etc/modprobe.d/ and in it put
options rtl8192cu debug=5
Then log out and log back in.
Use Ksyslog, or dmesg or journalctl to keep track of the debug reports.

[theodorn]

I ran the following command sequence, I got on askubuntu earlier this year. I've used it on Ubuntu Studio 15.10, and Mate 16.04, before I ran it on my live Kubuntu install. The connection has not gone down for about twenty minutes, but the network key is still not saved, so I keep it in a text file on my desktop.

sudo apt-get update
sudo apt-get install git linux-headers-generic build-essential dkms
git clone [URL]https://github.com/pvaret/rtl8192cu-fixes.git[/URL]
sudo dkms add ./rtl8192cu-fixes
sudo dkms install 8192cu/1.10
sudo depmod -a
sudo cp ./rtl8192cu-fixes/blacklist-native-rtl8192.conf /etc/modprobe.d/

Edit I have no idea what the individual commands do, I just know it improves my wifi connection, at least on three Ubuntu flavors.

[GreyGeek]

There are a couple of new ones in that sequence that I've never seen before. Most of the info below is from the man pages. Sudo is used to execute the commands with root permission.

sudo apt-get update
Get a fresh list of packages from the repository

sudo apt-get install git linux-headers-generic build-essential dkms
Install the four packages.

git clone https://github.com/pvaret/rtl8192cu-fixes.git
Git is the very nice version control system created by Linus Torvolds to control kernel development. It is pulling the source code from the git repository and saving it on the local HD.
This particular pull is for the Realtek 8192 chipset driver, ported to kernel 3.11, but "This is a repackaging of Realtek's own 8192CU USB WiFi driver for Ubuntu 13.10 and later."
It has issues with Ubuntu's 16.04 release: https://github.com/pvaret/rtl8192cu-fixes/issues/77
so it probably may not work for my old Acer 7739 running Kubuntu 16.04.

sudo dkms add ./rtl8192cu-fixes
Dkms is a framework which allows kernel modules to be dynamically built for each kernel on your system in a simplified and organized fashion. The "add" parameter adds a module/module-version combination to the tree for builds and installs.

sudo dkms install 8192cu/1.10
Installs a built module/version combo onto the kernel it was built for, in this case module 8192cu, version 1.10.

sudo depmod -a
Depmod creates a list of module dependencies by reading each module under /lib/modules/version and determining what symbols it exports and what symbols it needs. By default, this list is written to modules.dep, and a binary hashed version named modules.dep.bin, in the same directory.

sudo cp ./rtl8192cu-fixes/blacklist-native-rtl8192.conf /etc/modprobe.d/
This command copies the conf file created by the dkms install command to the /etc/modprobe,d/ directory. In that conf file are blacklist and possibly options commands that control the loading of modules and their settings.

All in all a very interesting set of commands. Thanks for the post, theodorn!

[theodorn]

GreyGeek, thank YOU for these detailed explanations. Some of this stuff is familiar to me, but the sequence as a whole, is quite cryptic, though it's more clear after reading your post. What I wanted to come across, was that I take no responsibility for anyone who runs the commands, as a script, or in part. The way I saw it, I just thought to myself, I've nothing to lose by trying this solution. I'm very careful to save all important files, so I can always reinstall, if I need to.

Fortunately, I haven't had to, after running this RTL8192CU-fix, for three times now. Still there might be other users having similar problems, and if a search for solutions will bring anyone to this thread, your mileage may vary. By the way, I think it's this bug, at least it explains in part what happened in my install. There are some solutions offered, but I haven't tried any of them.

https://bugs.launchpad.net/ubuntu/+s...t/+bug/1569674