External wifi chip does not stay connected to the internet

[gretha2]

I have a Lenovo t440s laptop and I have dual booted Ubuntu 14.04.1 and Windows 8.1. The internal wifi chip is not recognized by ubuntu so I bought an Edimax EW-7811Un. It connects to my wifi for about 3 minutes and disconnects. If I unplug the edimax and plug it back in, it works for another 3 minutes. What can I do to make the connection more stable?

[praseodym]

Please open a terminal with CTRL+ALT+T and show the outputs of these commands:


lspci -nnk | grep -iA2 net
lsusb
lsmod
iwconfig
rfkill list
Does LAN work?

[mikewhatever]

Here is the bug report: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/852190
It's been three years, and the in kernel driver still doesn't work well.

[praseodym]

That Edimax stick should work with this driver change:

http://forum.ubuntuusers.de/topic/wlan-stick-524440/3/#Realtek-rtl8192cu-s-Treiber-fuer-12-04-4-und-13-10-fuer-Kernel-3-11

But there should also be an internal card...

[gretha2]

Please open a terminal with CTRL+ALT+T and show the outputs of these commands:
Code:
lspci -nnk | grep -iA2 net
lsusb
lsmod
iwconfig
rfkill list
Does LAN work?


gretha@gds:~$ lspci -nnk | grep -iA2 net
00:19.0 Ethernet controller [0200]: Intel Corporation Ethernet Connection I218-LM [8086:155a] (rev 04)
Subsystem: Lenovo Device [17aa:2214]
Kernel driver in use: e1000e
--
03:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. RTL8192EE PCIe Wireless Network Adapter [10ec:818b]
Subsystem: Realtek Semiconductor Co., Ltd. Device [10ec:001b]
gretha@gds:~$ lsusb
Bus 001 Device 002: ID 8087:8000 Intel Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 004: ID 04f2:b39a Chicony Electronics Co., Ltd
Bus 002 Device 002: ID 138a:0017 Validity Sensors, Inc.
Bus 002 Device 010: ID 7392:7811 Edimax Technology Co., Ltd EW-7811Un 802.11n Wireless Adapter [Realtek RTL8188CUS]
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
gretha@gds:~$ lsmod
Module Size Used by
arc4 12608 2
rtl8192cu 67723 0
rtl_usb 18448 1 rtl8192cu
rtlwifi 63475 2 rtl_usb,rtl8192cu
rtl8192c_common 53172 1 rtl8192cu
mac80211 630653 3 rtl_usb,rtlwifi,rtl8192cu
cfg80211 484040 2 mac80211,rtlwifi
rfcomm 69160 0
bnep 19624 2
nls_iso8859_1 12713 1
snd_hda_codec_hdmi 46254 1
snd_hda_codec_realtek 61438 1
uvcvideo 80885 0
videobuf2_vmalloc 13216 1 uvcvideo
videobuf2_memops 13362 1 videobuf2_vmalloc
videobuf2_core 40664 1 uvcvideo
videodev 134688 2 uvcvideo,videobuf2_core
intel_rapl 18773 0
x86_pkg_temp_thermal 14205 0
intel_powerclamp 14705 0
coretemp 13435 0
kvm 451511 0
crct10dif_pclmul 14289 0
crc32_pclmul 13113 0
ghash_clmulni_intel 13216 0
aesni_intel 55624 0
aes_x86_64 17131 1 aesni_intel
lrw 13286 1 aesni_intel
gf128mul 14951 1 lrw
glue_helper 13990 1 aesni_intel
ablk_helper 13597 1 aesni_intel
cryptd 20359 3 ghash_clmulni_intel,aesni_intel,ablk_helper
thinkpad_acpi 81013 1
joydev 17381 0
nvram 14411 1 thinkpad_acpi
serio_raw 13462 0
snd_seq_midi 13324 0
snd_seq_midi_event 14899 1 snd_seq_midi
lpc_ich 21080 0
mei_me 18627 0
mei 82276 1 mei_me
btusb 32412 0
snd_hda_intel 52355 12
bluetooth 391196 11 bnep,btusb,rfcomm
snd_hda_codec 192906 3 snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_i ntel
snd_rawmidi 30144 1 snd_seq_midi
snd_hwdep 13602 1 snd_hda_codec
snd_pcm 102099 4 snd_hda_codec_hdmi,snd_hda_codec,snd_hda_intel
snd_seq 61560 2 snd_seq_midi_event,snd_seq_midi
snd_seq_device 14497 3 snd_seq,snd_rawmidi,snd_seq_midi
snd_page_alloc 18710 2 snd_pcm,snd_hda_intel
wmi 19177 0
snd_timer 29482 2 snd_pcm,snd_seq
snd 69238 35 snd_hda_codec_realtek,snd_hwdep,snd_timer,snd_hda_ codec_hdmi,snd_pcm,snd_seq,snd_rawmidi,snd_hda_cod ec,snd_hda_intel,thinkpad_acpi,snd_seq_device,snd_ seq_midi
i915 783805 8
soundcore 12680 1 snd
video 19476 1 i915
drm_kms_helper 53081 1 i915
intel_smartconnect 12619 0
drm 303102 7 i915,drm_kms_helper
mac_hid 13205 0
i2c_algo_bit 13413 1 i915
parport_pc 32701 0
ppdev 17671 0
lp 17759 0
parport 42348 3 lp,ppdev,parport_pc
e1000e 254433 0
psmouse 106678 0
ahci 25819 4
ptp 18933 1 e1000e
libahci 32560 1 ahci
rtsx_pci 45956 0
pps_core 19382 1 ptp
gretha@gds:~$ iwconfig
eth0 no wireless extensions.

lo no wireless extensions.

wlan0 IEEE 802.11bgn ESSID:"LFWN1"
Mode:Managed Frequency:2.412 GHz Access Point: 00:1F:90:E9:2A:B0
Bit Rate=18 Mb/s Tx-Power=20 dBm
Retry long limit:7 RTS thr=2347 B Fragment thr:off
Power Management:off
Link Quality=30/70 Signal level=-80 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:149 Missed beacon:0

gretha@gds:~$ rfkill list
1: tpacpi_bluetooth_sw: Bluetooth
Soft blocked: yes
Hard blocked: no
7: phy5: Wireless LAN
Soft blocked: no
Hard blocked: no

LAN does work

[praseodym]

Change the driver for the stick:


sudo apt-get install --reinstall linux-headers-$(uname -r) linux-headers-generic build-essential dkms git
git clone https://github.com/pvaret/rtl8192cu-fixes.git
sudo dkms add ./rtl8192cu-fixes
sudo dkms install 8192cu/1.9
echo "blacklist rtl8192cu" | sudo tee -a /etc/modprobe.d/blacklist.conf
Reload the driver:


sudo modprobe -rv rtl8192cu
sudo modprobe -v 8192cu
Replug the stick. Then load the driver for the internal card:


sudo modprobe -v rtl8188ee
and check the outputs of:


ifconfig -a
iwconfig
iwlist chan
lsmod
sudo iwlist scan
dmesg | egrep 'rtl8|8192'
grep rtl8 /etc/modprobe.d/*
cat /etc/modules

[gretha2]

Change the driver for the stick:


sudo apt-get install --reinstall linux-headers-$(uname -r) linux-headers-generic build-essential dkms git
git clone https://github.com/pvaret/rtl8192cu-fixes.git
sudo dkms add ./rtl8192cu-fixes
sudo dkms install 8192cu/1.9
echo "blacklist rtl8192cu" | sudo tee -a /etc/modprobe.d/blacklist.conf
Reload the driver:


sudo modprobe -rv rtl8192cu
sudo modprobe -v 8192cu
Replug the stick. Then load the driver for the internal card:


sudo modprobe -v rtl8188ee
and check the outputs of:


ifconfig -a
iwconfig
iwlist chan
lsmod
sudo iwlist scan
dmesg | egrep 'rtl8|8192'
grep rtl8 /etc/modprobe.d/*
cat /etc/modules

gretha@gds:~$ ifconfig -a
eth0 Link encap:Ethernet HWaddr 28:d2:44:89:7f:d4
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:5312 errors:0 dropped:0 overruns:0 frame:0
TX packets:4113 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:6996971 (6.9 MB) TX bytes:374546 (374.5 KB)
Interrupt:20 Memory:f0600000-f0620000

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:455 errors:0 dropped:0 overruns:0 frame:0
TX packets:455 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:40614 (40.6 KB) TX bytes:40614 (40.6 KB)

wlan0 Link encap:Ethernet HWaddr 80:1f:02:f5:27:a6
inet addr:192.168.1.10 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::821f:2ff:fef5:27a6/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:70 errors:0 dropped:5 overruns:0 frame:0
TX packets:111 errors:0 dropped:2 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:15067 (15.0 KB) TX bytes:20298 (20.2 KB)

gretha@gds:~$ iwconfig
eth0 no wireless extensions.

lo no wireless extensions.

wlan0 IEEE 802.11bg ESSID:"LFWN1" Nickname:"<WIFI@REALTEK>"
Mode:Managed Frequency:2.412 GHz Access Point: 00:1F:90:E9:2A:B0
Bit Rate:54 Mb/s Sensitivity:0/0
Retry:off RTS thr:off Fragment thr:off
Power Management:off
Link Quality=100/100 Signal level=96/100 Noise level=0/100
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0

gretha@gds:~$ iwlist chan
eth0 no frequency information.

lo no frequency information.

wlan0 11 channels in total; available frequencies :
Channel 01 : 2.412 GHz
Channel 02 : 2.417 GHz
Channel 03 : 2.422 GHz
Channel 04 : 2.427 GHz
Channel 05 : 2.432 GHz
Channel 06 : 2.437 GHz
Channel 07 : 2.442 GHz
Channel 08 : 2.447 GHz
Channel 09 : 2.452 GHz
Channel 10 : 2.457 GHz
Channel 11 : 2.462 GHz
Current Frequency:2.412 GHz (Channel 1)

gretha@gds:~$ lsmod
Module Size Used by
rtl8188ee 89677 0
rtl_pci 26690 1 rtl8188ee
rtlwifi 63475 2 rtl_pci,rtl8188ee
mac80211 630653 3 rtl_pci,rtlwifi,rtl8188ee
cfg80211 484040 2 mac80211,rtlwifi
8192cu 527283 0
rfcomm 69160 0
bnep 19624 2
nls_iso8859_1 12713 1
snd_hda_codec_hdmi 46254 1
snd_hda_codec_realtek 61438 1
uvcvideo 80885 0
videobuf2_vmalloc 13216 1 uvcvideo
videobuf2_memops 13362 1 videobuf2_vmalloc
videobuf2_core 40664 1 uvcvideo
videodev 134688 2 uvcvideo,videobuf2_core
snd_hda_intel 52355 5
snd_hda_codec 192906 3 snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_i ntel
snd_hwdep 13602 1 snd_hda_codec
snd_pcm 102099 3 snd_hda_codec_hdmi,snd_hda_codec,snd_hda_intel
snd_page_alloc 18710 2 snd_pcm,snd_hda_intel
thinkpad_acpi 81013 1
nvram 14411 1 thinkpad_acpi
snd_seq_midi 13324 0
snd_seq_midi_event 14899 1 snd_seq_midi
snd_rawmidi 30144 1 snd_seq_midi
intel_rapl 18773 0
x86_pkg_temp_thermal 14205 0
snd_seq 61560 2 snd_seq_midi_event,snd_seq_midi
intel_powerclamp 14705 0
coretemp 13435 0
kvm 451511 0
crct10dif_pclmul 14289 0
crc32_pclmul 13113 0
ghash_clmulni_intel 13216 0
aesni_intel 55624 0
aes_x86_64 17131 1 aesni_intel
lrw 13286 1 aesni_intel
gf128mul 14951 1 lrw
glue_helper 13990 1 aesni_intel
ablk_helper 13597 1 aesni_intel
cryptd 20359 3 ghash_clmulni_intel,aesni_intel,ablk_helper
snd_seq_device 14497 3 snd_seq,snd_rawmidi,snd_seq_midi
joydev 17381 0
serio_raw 13462 0
snd_timer 29482 2 snd_pcm,snd_seq
snd 69238 22 snd_hda_codec_realtek,snd_hwdep,snd_timer,snd_hda_ codec_hdmi,snd_pcm,snd_seq,snd_rawmidi,snd_hda_cod ec,snd_hda_intel,thinkpad_acpi,snd_seq_device,snd_ seq_midi
rtsx_pci_ms 18151 0
btusb 32412 0
bluetooth 391196 11 bnep,btusb,rfcomm
lpc_ich 21080 0
memstick 16966 1 rtsx_pci_ms
mei_me 18627 0
mei 82276 1 mei_me
wmi 19177 0
soundcore 12680 1 snd
i915 783805 5
video 19476 1 i915
drm_kms_helper 53081 1 i915
mac_hid 13205 0
intel_smartconnect 12619 0
drm 303102 4 i915,drm_kms_helper
i2c_algo_bit 13413 1 i915
parport_pc 32701 0
ppdev 17671 0
lp 17759 0
parport 42348 3 lp,ppdev,parport_pc
rtsx_pci_sdmmc 23274 0
e1000e 254433 0
psmouse 106678 0
ahci 25819 4
ptp 18933 1 e1000e
libahci 32560 1 ahci
rtsx_pci 45956 2 rtsx_pci_ms,rtsx_pci_sdmmc
pps_core 19382 1 ptp
gretha@gds:~$ sudo iwlist scan
eth0 Interface doesn't support scanning.

lo Interface doesn't support scanning.

wlan0 Scan completed :
Cell 01 - Address: 00:1F:90:E9:2A:B0
ESSID:"LFWN1"
Protocol:IEEE 802.11bg
Mode:Master
Frequency:2.412 GHz (Channel 1)
Encryption key:on
Bit Rates:54 Mb/s
Quality=100/100 Signal level=95/100

gretha@gds:~$ dmesg | egrep 'rtl8|8192'
[ 0.000000] PERCPU: Embedded 29 pages/cpu @ffff88031e200000 s86336 r8192 d24256 u262144
[ 0.000000] pcpu-alloc: s86336 r8192 d24256 u262144 alloc=1*2097152
[ 0.458648] UDP hash table entries: 8192 (order: 6, 262144 bytes)
[ 0.458779] UDP-Lite hash table entries: 8192 (order: 6, 262144 bytes)
[ 411.665023] 8192cu: module verification failed: signature and/or required key missing - tainting kernel
[ 411.667499] usbcore: registered new interface driver rtl8192cu
gretha@gds:~$ grep rtl8 /etc/modprobe.d/*
/etc/modprobe.d/blacklist.conf:blacklist rtl8192cu
/etc/modprobe.d/blacklist.conf:blacklist rtl8192cu
gretha@gds:~$ cat /etc/modules
# /etc/modules: kernel modules to load at boot time.
#
# This file contains the names of kernel modules that should be loaded
# at boot time, one per line. Lines beginning with "#" are ignored.
# Parameters can be specified after the module name.

lp
rtc

edit: connection seems to be stable now.

[praseodym]

Are you connected via internal card?


cat /etc/udev/rules.d/70-persistent-net.rules
arp -v

[varunendra]

While posting the outputs, please use 'Code' tags. It preserves the output's formatting and makes the post cleaner, compact and more readable. To see a quick 'HowTo' with screenshots, please follow the "Use Code Tags" link in my signature.