Wifi connects but after some time internet wont work

[Mahesh Krishna]

I have Edimax EW-7811Un 802.11n Wireless USB Adapter [Realtek RTL8188CUS] connected to my pc.
Wifi drivers are installed properly and I am able to connect to wifi
but after sometime (less than a minute) there is no internet
I tried to ping 8.8.8.8 thinking it could be dns problem but ping fails.
It works fine in windows os

[Mahesh Krishna]

I am using Debian 9 stretch

[bw123]

According to the wiki, that device is USB: 7392:7811 Edimax Technology Co., Ltd EW-7811Un 802.11n Wireless Adapter [Realtek RTL8188CUS]
https://wiki.debian.org/rtl819x

Modinfo shows it is supported in the kernel, mentions firmware.

Code: Select all

# modinfo rtl8192cu | grep -e 7811 -e firm
firmware:       rtlwifi/rtl8192cufw_TMSC.bin
firmware:       rtlwifi/rtl8192cufw_B.bin
firmware:       rtlwifi/rtl8192cufw_A.bin
firmware:       rtlwifi/rtl8192cufw.bin
alias:          usb:v7392p7811d*dc*dsc*dp*ic*isc*ip*in*
# uname -a
Linux themini 4.9.0-6-amd64 #1 SMP Debian 4.9.82-1+deb9u3 (2018-03-02) x86_64 GNU/Linux


So I'm confused about whether you have the firmware installed like the wiki says, or whether you have installed another driver from somewhere else that might be conflicting with the kernel driver?

[Dai_trying]

Could be another example of random mac address failing the wifi, you could try putting this into /etc/NetworkManager/NetworkManager.conf, it has helped quite a few people with a similar issue.

Code: Select all

[device]
wifi.scan-rand-mac-address=no


[Mahesh Krishna]

Thanks for the reply.
I followed wiki to install wifi drivers.
I even disabled the random mac address changing

[Mahesh Krishna]

I don't know if other drivers are conflicting
If there are other installed drivers conflicting with the wifi drivers! how do i remove them?

[sunrat]

I followed wiki to install wifi drivers.

The wiki says the drivers are already included in the kernel, no need to install. I assume you meant to say you installed firmware. It may be just terminology but it means different things.

I don't know if other drivers are conflicting
If there are other installed drivers conflicting with the wifi drivers! how do i remove them?

Check with

Code: Select all

lsmod |grep rtl

It's unlikely but possible. If it connects but drops out it's probably something else.

I have exactly the same problem and still haven't managed to fix it. I just disconnect/reconnect in network mangler. Could be something as simple as the location of the device getting interference.

[stevepusser]

I followed wiki to install wifi drivers.

The wiki says the drivers are already included in the kernel, no need to install. I assume you meant to say you installed firmware. It may be just terminology but it means different things.

I don't know if other drivers are conflicting
If there are other installed drivers conflicting with the wifi drivers! how do i remove them?

Check with

Code: Select all

lsmod |grep rtl

It's unlikely but possible. If it connects but drops out it's probably something else.

I have exactly the same problem and still haven't managed to fix it. I just disconnect/reconnect in network mangler. Could be something as simple as the location of the device getting interference.

Is there any way to disable the power saving for the driver in a .conf file? That's often the cure for random disconnects.

[sunrat]

Is there any way to disable the power saving for the driver in a .conf file? That's often the cure for random disconnects.

Could try this:

As root, create a file /etc/modprobe.d/8192cu.conf with the following contents:
options 8192cu rtw_power_mgnt=0 rtw_enusbss=0

Stolen from https://forum.doozan.com/read.php?6,8618,8938

[Mahesh Krishna]

Still did not find any solution
In the Networkmanager applet it shows pc is connected to wifi network.
After sometime I cant ping any outside ip(no internet) not even default gateway.
But still pc is connected to wifi

[Dai_trying]

I had this problem with a usb device and found I needed to install driver from this github repo but it appears to now be deprecated but it is still in use on the other machine and working fine. Might be worth trying to see if it works for you.