ubuntu-notes.md

Ubuntu notes

• Desktop: I/O
  • PrintScreen modifiers
  • Adding shell alias
  • Split file, zip parts, unzip and join
• Desktop: Applications
  • Disk usage
  • Adding shell script to apps list
  • JetBrains ecosystem
  • Ctrl + Shift language switch
  • Dual boot timezone fix
  • Install .deb package manually
  • Remove invalid apt repository (PPA)
• Desktop: Drivers
  • Gnome Disks (GUI)
  • boot-repair (GUI)
  • Archer T3U Plus
• Server
  • User creation
  • Installing nginx
  • MySQL read-only mode
  • Reverse SSH tunnel
  • SSH key autoload
  • SSH SOCKS proxy
  • Tunneling through SOCKS
  • docker-compose on Ubuntu 20

Desktop: I/O

PrintScreen modifiers

Adding shell alias ^↗

1. Make sure your ~/.bashrc file has the following lines or append them:

   if [ -f ~/.bash_aliases ]; then
       . ~/.bash_aliases
   fi

2. Open ~/.bash_aliases

3. Add required aliases, for example alias work='cd ~/work'

4. Save and close the file

5. Tell the system to reload aliases: source ~/.bash_aliases

6. Alias can be removed with unalias {alias_name}

   • Remove all aliases: unalias -a

Split file, zip parts, unzip and join

split -b 20m dimg dimg.part
zip -r dimg.zip dimg*
...
unzip dimg.zip -d .
cat dimg.part* > dimg

Desktop: Applications

Disk usage ^↗

df -h

Adding shell script to apps list ^↗

1. Create new file:

   touch ~/.local/share/applications/{Your App Name}.desktop

2. Put contents:

   [Desktop Entry]
   # Define which specification version this entry is using 
   Version=1.0
   # The application name (eg. "Gnome Terminal", "Firefox")
   Name=My Awesome App
   # The generic app name (eg. "Terminal", "Web Browser")
   GenericName=Awesome App
   # The Tooltip
   Comment=This app is awesome!
   # The command you want to execute
   Exec=/path/to/sh/file/file.sh
   # Whether the app should run in a terminal window
   Terminal=false
   # The pretty picture :D
   Icon=/opt/PhpStorm-103.243/bin/webide.png
   # The type of the desktop entry (Application, Link, or Directory)
   Type=Application

JetBrains ecosystem ^↗

1. Download and install latest .tar.gz from jetbrains.com
2. Install required IDEs via Toolbox

   sudo -i
   mkdir /opt/jetbrains-toolbox
   tar -xzf jetbrains-toolbox-1.21.9712.tar.gz -C /opt/jetbrains-toolbox --strip-components=1
   chmod -R +rwx /opt/jetbrains-toolbox
   touch /opt/jetbrains-toolbox.sh
   echo '#!/bin/bash' >> /opt/jetbrains-toolbox.sh
   echo '/opt/jetbrains-toolbox/jetbrains-toolbox' >> /opt/jetbrains-toolbox.sh  # TODO investigate (strip-comps)
   ln -s /opt/jetbrains-toolbox.sh /usr/local/bin/jetbrains-toolbox
   chmod -R +rwx /usr/local/bin/jetbrains-toolbox
   rm jetbrains-toolbox-1.21.9712.tar.gz
   jetbrains-toolbox

Ctrl + Shift language switch ^↗

For Ubuntu 18.04 LTS, 20.04 LTS, 20.10 and 21.04 with GNOME desktop:

1. Install GNOME Tweaks sudo apt-get install gnome-tweaks
2. Then open (gnome-tweaks).
3. Select Keyboard & Mouse tab
4. Click Additional Layout Options button
5. Expand Switching to another layout
6. Select Ctrl + Shift here
   • It also breaks "Ctrl + Shift + {X}" normal work in most of the cases.

Dual boot timezone fix ^↗

• Fixes system time shift on OS switching

  sudo timedatectl set-local-rtc 1 

CLI markdown rendering ^↗

curl -L -o glow_1.4.1_linux_amd64.deb https://github.com/charmbracelet/glow/releases/download/v1.4.1/glow_1.4.1_linux_amd64.deb
sudo dpkg -i glow_1.4.1_linux_amd64.deb

Install .deb package manually ^↗

sudo dpkg -i DEB_PACKAGE

Remove invalid apt repository (PPA) ^↗

cd /etc/apt/sources.list.d
ls -la
rm ...

Desktop: Drivers

Gnome Disks (GUI) ^↗

• Disk format and partitioning
• Filesystem & bootsectors backup/restore

  sudo apt-get install gnome-disk-utility
  gnome-disks

boot-repair (GUI) ^↗

• Recovery/install MBR partition tables
• GRUB bootloader
• GPT disk drives

  sudo add-apt-repository ppa:yannubuntu/boot-repair && \
       apt-get update && \
       apt-get install -y boot-repair && \
       boot-repair 

Archer T3U Plus ^↗

• USB WiFi adapter drivers for Ubuntu 18/20/21

  sudo apt update && \
       apt install git dkms build-essential linux-headers-generic && \
       git clone https://github.com/morrownr/88x2bu.git && \
       cd 88x2bu && \
       sudo ./install-driver.sh

Server

User creation ^↗

ssh root@{server_ip}
adduser delameter
usermod -aG sudo delameter
ufw app list
ufw allow OpenSSH
ufw enable
ufw status

Installing nginx ^↗

sudo apt update
sudo apt install nginx
sudo ufw app list
sudo ufw allow 'Nginx HTTP'
sudo ufw status
systemctl status nginx

MySQL read-only mode

• Enable Read-Only Mode

  FLUSH TABLES WITH READ LOCK;
  SET GLOBAL read_only = 1;

• Disable Read-Only Mode

  SET GLOBAL read_only = 0;
  UNLOCK TABLES;

Reverse SSH tunnel ^↗

1. On target host:

   ssh -fN -R 10022:localhost:22 dlup.link
   

2. On relay host:

   ssh -p 10022 localhost
   

SSH key autoload ^↗

• Launch ssh agent:

  eval "$(ssh-agent -s)"
  ssh-add ~/.ssh/github
  
  touch ~/.ssh/config
  chmod 600 ~/.ssh/config
  nano ~/.ssh/config

• .ssh/config:

  Host github.com
      IdentityFile ~/.ssh/github
  
  # @TODO havent tried yet
  #   AddKeysToAgent  yes
  

SSH SOCKS proxy ^↗

• Creates proxy that listens 127.0.0.1:1905:

   ssh -fN4 -D 1905 dlup.link
  

Tunneling through SOCKS

• curl

  --proxy socks5h://127.0.0.1:1488
  

• apt ^↗

  sudo -i 'Acquire::http::proxy "socks5h://localhost:1488";' >> /etc/apt/apt.conf.d/12proxy
  sudo apt install
  sudo sed -i 's/^Acquire/#Acquire/' /etc/apt/apt.conf.d/12proxy

docker-compose on Ubuntu 20 ^↗

$ sudo curl -L "https://github.com/docker/compose/releases/download/1.29.2/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
$ sudo chmod +x /usr/local/bin/docker-compose
$ docker-compose --version
docker-compose version 1.29.2, build 5becea4c