I have problems with my Wi-Fi connection - TUXEDO Computers

Unfortunately, there are always problems with Wi-Fi networks. Especially when new devices are integrated into an existing network, there can be numerous problem causes
Please check the following in advance:

- The available IP addresses may be exhausted or e.g. MAC filters on the router may be active.
- Within your router software is the configuration set to "Wifi access only for known devices" or similar!
- Different encryption settings can become a problem. Please check the settings on the router and in the WLAN connection in the system.
- Many WLAN routers have energy-saving options that reduce the signal strength to a minimum. If you then move with the device, connection breaks or very bad connections may occur. Please check the power settings of your router!
- It is generally helpful to reset the network once when integrating new devices, so that any hindering settings are removed (e.g. IP address pool). In addition, all devices should then obtain their IP addresses automatically or they should all be permanently configured. A mixed configuration sometimes causes problems
- If problems persist, log off all devices from the network and only log them back on one by one. In this way, possible sources of interference can still be identified.
- Sometimes it helps to set the IPv6 mode to "ignore" in the connection settings in the system. SO only IPv4 is used for the connection, which usually works more stable.

Special problems:
1. you often have disconnections and receive the message "[...] Connection disconnected (reason -3)" in the syslog.
Please open a terminal and enter the following command:
sudo cp /etc/modprobe.d/iwlwifi.conf /etc/modprobe.d/iwlwifi.conf.bak
sudo echo "options iwlwifi 11n_disable=1" | sudo tee /etc/modprobe.d/iwlwifi.conf
sudo reboot

This deactivates the "N" network, which usually leads to significant connection stability.
If the change does not help, you can restore the file from the backup:

sudo rm /etc/modprobe.d/iwlwifi.conf
sudo cp /etc/modprobe.d/iwlwifi.conf.bak /etc/modprobe.d/iwlwifi.conf

• Connection interruptions in the 5 GHz radio network

If you experience frequent disconnects in the 5 GHz radio network, this may be due to the fact that your router receives radar signals and these have priority over the wifi signal, thus temporarily disabling wireless. The source of the radar signals can be privileged users such as air traffic control, military or weather services. AVM's FRITZ!Box usually takes care of this itself, as it initially only releases radio channels 36 to 48 in the 5 GHz radio network after a restart. The check which goes by Zero Wait DFS (Dynamic Frequency Selection) can take up to 10 minutes, during which time the FRITZ!Box automatically switches to the 2.4 GHz network. Only after the check for privileged users in the higher channels, the channels 52 to 140 are released for your wifi chip. This check also takes place periodically during operation. For the automatic switch to work, the same names must be assigned in the FRITZ!Box for the 2.4 GHz and 5 GHz radio network. In the log of your router you can find out if radar from privileged users are the reason for your dropouts. If you experience frequent dropouts, you can restrict the 5 GHz band to channels 36, 40, 44 and 48 in the settings. Routers that lack the DFS feature are only allowed to use channels up to 48 in the EU.

2. No WLAN networks are displayed
This is usually the case if the WLAN card was not recognized because, for example, the appropriate drivers for the kernel used are missing.
First we check which WLAN chipset is in the device:

lspci

In the output we are looking for the suitable network controller, e.g:
04:00.0 Network controller: Intel Corporation Wireless 3160 (rev 83)

Depending on the chipset and kernel version you can download the driver file here: https://wireless.wiki.kernel.org/en/users/Drivers/iwlwifi
The respective download always contains an "iwlwifi-******.ucode" file, which must be copied to "/lib/firmware" (as sudo). After a restart the drivers should be found and loaded automatically.

3. The Wi-Fi connection only works in the immediate vicinity of the router
In this case, it is likely that there is a problem with the wireless LAN antennas in the device.
You are welcome to check yourself whether, for example, the antenna cables are connected to the WLAN module. Opening the device does not automatically void the warranty.

If the antenna cables are connected to the WLAN module, they could also be damaged (the cables run through the entire device). Please contact our support for a repair.

4. In some cases of unstable connections the fine tuning of the Powersafe mode is sufficient:
sudo nano /etc/NetworkManager/conf.d/default-wifi-powersave-on.confThere you set the value for wifi.powersave from 3 to 2.