Linux Red Hat Ubuntu

Vi (or Vim) session no longer responding?

If your Vi or Vim session is hanging and is not responding to anything, then it might be because you pressed CTRL+S accidentally (out of habbit). To fix this, just press CTRL+Q to unblock the session.

Dell XPS15 Laptop Linux Ubuntu

No wifi or no external monitor on Dell XPS-15

If your wifi card is not available after booting your Dell XPS-15 laptop (with Ubuntu 20.04 or 22.04), or your external monitor refuses to display anything, please try the following:

start up your laptop without your power supply plugged in, connect with wifi, and/or your external monitor and only then plug in your power supply.

This fix works everytime for me.


Ubuntu: reset monitor settings to default

If you want to reset your monitor settings to default through the terminal (your second screen is broken and the settings are ‘shown’ there and you don’t want to restart your laptop), you can use the following command:

xrandr -s 0
Linux Ubuntu

Ubuntu Server – CTRL-ALT-DEL

If you press CTRL-ALT-DEL on a Ubuntu Server the server will be shut down without asking any confirmation or password. This is of course not a good idea.

To disable this, enter the following commands as root:

systemctl mask
systemctl daemon-reload
Databases DBeaver MySQL

DBeaver: refresh data not showing

If you try to refresh the data in a table while using DBeaver, and no changes are shown, it could be that you are in transactional mode.

To fix this, click on the menu ‘Database’ and select ‘Transaction mode’. Select ‘Auto-commit’ and ‘Serializable’.


Linux: removing commands from history

If you want to remove some commands from your bash history use the following command:

history -d 1001

where 1001 is the number of the history line. Of course this might add another problem: the command ‘history -d 1001’ is now added to your history.

How to avoid a command getting in your bash history?

If you want to execute a command and don’t want it to get in your history list (because it contains sensitive data, or you just don’t want to clutter your history), start the command with a space.

For this to work the environment variable $HISTCONTROL has to be set to ‘ignorespace’ or ‘ignoreboth’.

export HISTCONTROL=ignorespace

Ubuntu 20.04: annoying popup ‘Authentication is required to run gvfsd-admin daemon’

If you get the above popup, and it is impossible to get it to go away (cancel does nothing, authenticate hangs…), here is a quick solution to get rid of it:

Press ALT+F2, enter ‘r’ (without the quotes) in the command box and press enter. This will restart Gnome and the window will be gone. Your running apps keep running!


Nextcloud: my files view is empty???

After a serious upgrade of my NextCloud server, I had the strange phenomenon that my files view was completely empty. Tried everything, nothing worked. In the end the cause was proven to be an extra folder in de data directory of Nextcloud.

I had copied all data from a usb drive and put it in a __filesfrompreviousserver folder in the /var/snap/nextcloud/common/nextcloud/data folder, which is the folder where NextCloud stores its data.

I never thought that would cause problems, but apparently it does. Once I removed the folder everything was fine again.


Ubuntu: external screen goes black, but ubuntu is still using 2 screens

Today I had the problem that my external screen was only showing a nice shade of black. However, several programs were running on that screen, and I could not just reboot the laptop without losing much work.

To fix this (it did fix it for me, your mileage may vary), open a terminal window (Ctrl + Alt + t) and type the following command:


After this, I had my second screen back.


Activate the Master Control Panel (AKA God Mode)

What is this? MCP adds an icon to your desktop that gives you near instant access to nearly every Windows setting available.

Activating this is really simple: just create a new folder on your desktop (right-click and select New -> Folder), and name it “GodMode.{ED7BA470-8E54-465E-825C-99712043E01C}”

This will create a new folder with the following icon:

Double-clicking this icon will open a list of settings.