Due to outdated servers.

Do this:

sudo sed -i "s/archive.ubuntu.com/us.archive.ubuntu.com/" /etc/apt/sources.list

Ubuntu 20 or later with GNOME automatically mounts external USB drives for logged-in console users. However, this feature doesn't work on headless servers. To auto-mount USB drives on a headless server, use this tool: 

https://github.com/raamsri/automount-usb

CMD

BASH

Install

sudo apt install vlock

Usage

vlock --current        # lock current terminal

vlock --all            # lock all termianls

$ sudo apt install power-profiles-daemon

$ powerprofilesctl set power-saver

$ powerprofilesctl

$ more /proc/cpuinfo | grep "cpu MHz"

Reference

• Enable hibernate, https://ubuntuhandbook.org/index.php/2021/08/enable-hibernate-ubuntu-21-10/
• CPU power mode, https://ubuntuhandbook.org/index.php/2023/10/command-cpu-power-mode-ubuntu-22-04/

Install upower

sudo apt-get install upower

Commands:

$ upower -e
$ upower -d
$ upower -i <object>

Configuration

/etc/UPower/UPower.conf

Service

$ sudo systemctl restart upower.service
$ sudo systemctl status upower.service

Alias

alias battery='upower -d | grep -m 2 -e '\''percentage'\'' -e '\''time to empty'\'' | sed '\''s/^[ \t]*//'\'''

For PowerShell v6.1 or later, use command like this:

> Show-Markdown [file name]

https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.utility/show-markdown?view=powershell-7.4

From CMD, you can call the cmdlet like below, after installing PowerShell 7.4:

"C:\Users\<your username>\AppData\Local\Microsoft\WindowsApps\Microsoft.PowerShell_8wekyb3d8bbwe\pwsh.exe" -Command "Show-Markdown %1"