tux-snippets

APT mirror:
  sed -i -- 's/deb.debian.org/mirror.netcologne.de/g' /etc/apt/sources.list.d/*
  
APT components:
  main contrib non-free non-free-firmware -> see end

APT external repos:
  apt install extrepo
  sed -i -E "s/# (- (contrib|non-free))/\1/g" /etc/extrepo/config.yaml
  apt update
  extrepo search [something] (https://salsa.debian.org/extrepo-team/extrepo-data/-/tree/master/repos/debian)
  extrepo enable:
    vscode
    docker-ce
    edge
    fasttrack: https://salsa.debian.org/extrepo-team/extrepo-data/-/blob/master/repos/debian/fasttrack.yaml
    mozilla
    node: https://salsa.debian.org/extrepo-team/extrepo-data/-/blob/master/repos/debian/nodesource.yaml
    nvidia-container:
      https://salsa.debian.org/extrepo-team/extrepo-data/-/commit/e90d33775190dbd70a4783dad02ef4b3c80153b2
      https://docs.nvidia.com/datacenter/cloud-native/container-toolkit/latest/install-guide.html#installing-with-apt
    onlyoffice-desktopeditors
    signal
    teamviewer_default:
      apt install teamvewer
      sudo rm /etc/apt/sources.list.d/teamviewer.list
    virtualbox: https://salsa.debian.org/extrepo-team/extrepo-data/-/blob/master/repos/debian/virtualbox.yaml

Pipx:
  apt install python3 pipx
  pipx ensurepath
  pipx completions
  register-python-argcomplete pipx | sudo tee /usr/share/bash-completion/completions/pipx

Python virtualenvwrapper:
  pipx install virtualenv
  pipx install virtualenvwrapper
  export WORKON_HOME=$HOME/.virtualenvs
  export VIRTUALENVWRAPPER_PYTHON=$HOME/.local/pipx/venvs/virtualenvwrapper/bin/python3.11
  source $HOME/.local/pipx/venvs/virtualenvwrapper/bin/virtualenvwrapper.sh
  alias workoff=deactivate

Diagnostics:
  lspci -k | grep -EA3 'VGA|3D|Display'
  lsmod | grep "kms\|drm"
  find /dev -group video
  cat /proc/cmdline
  find /etc/modprobe.d/
  cat /etc/modprobe.d/*kms*
  ls /etc/X11/xorg.conf
  glxinfo | grep -i "vendor\|rendering"
  grep LoadModule /var/log/Xorg.0.log
  lstopo

Packages:
  backports:
    linux-image-amd64
    linux-headers-amd64
    iotop
    latencytop
    mpv
    git-lfs
    man-db
    qalculate-gtk
    Laptops:
      powertop
      tlp
    Logitech:
      solaar (backports) https://github.com/pwr-Solaar/Solaar
  build-essential dkms firmware-linux
  sysfsutils nvme-cli
  gvfs-backends gvfs-fuse nfs-common cifs-utils
  curl jq ca-certificates
  docker-ce docker-compose-plugin
  wireguard 7zip
  python3 python3-dev
  fonts-noto
  ncdu
  
  Nvidia:
    nvidia-driver
    nvidia-xconfig
    cuda-drivers

Pipx packages:
  pre-commit
  yt-dlp
  
Change default editor:
  sudo update-alternatives --config editor

LightDM auto login:
  /etc/lightdm/lightdm.conf.d/10-autologin.conf
    [Seat:*]
    autologin-user=username
    autologin-user-timeout=0

Default systemd timeouts:
  /etc/systemd/system.conf
  /etc/systemd/user.conf

Allow long-running user services:
  loginctl enable-linger [user]

Change username safely:
  [[logout]]
  exec sudo -i
  killall -u [oldname]
  id [oldname]
  usermod -l [newname] [oldname]
  groupmod -n [newname] [oldname]
  usermod -d /home/[newname] -m [newname]
  usermod -c "[full name (new)]" [newname]
  id [newname]

NTP:
  ntpq -p

Show mouse params:
  xinput list | cut -f2 | cut -f2 -d'=' | \
    xargs -d $'\n' -I'{}' sh -c "xinput list-props '{}' | grep -iq scroll  &&  \
      (echo Listing dev id '{}'; xinput list-props '{}')"

Show kernel module params:
  modinfo -p [module]        # explanation
  systool -m [module] -av    # currently set

Analyze boot time:
  systemd-analyze [blame|critical-chain]

Scan ports:
  nc -w 1 -vz [ip] [start-port]-[end-port]

Delete duplicate files
  fdupes -rdN .

Rust:
  https://rustup.rs
  Update all cargo tools:
    sudo apt install pkg-config libgit2-dev libssh-dev libssl-dev
    cargo install cargo-update
    cargo install-update -a
  Packages:
    bottom lsd eza fd-find hyperfine binocle du-dust fclones

GNU find best practices:
  https://unix.stackexchange.com/questions/321697/why-is-looping-over-finds-output-bad-practice

APT sources:
  debian-stable.sources:
    Types: deb deb-src
    URIs: https://debian.netcologne.de/debian
    Suites: bookworm bookworm-updates
    Components: main contrib non-free non-free-firmware
    Signed-By: /usr/share/keyrings/debian-archive-keyring.gpg

    Types: deb deb-src
    URIs: https://security.debian.org/debian-security
    Suites: bookworm-security
    Components: main contrib non-free non-free-firmware
    Signed-By: /usr/share/keyrings/debian-archive-keyring.gpg

  debian-backports.sources:
    Types: deb deb-src
    URIs: https://debian.netcologne.de/debian
    Suites: bookworm-backports
    Components: main contrib non-free non-free-firmware
    Signed-By: /usr/share/keyrings/debian-archive-keyring.gpg

  nvidia.sources:
    Types: deb
    URIs: https://developer.download.nvidia.com/compute/cuda/repos/debian12/x86_64
    Suites: /
    Signed-By: /usr/share/keyrings/cuda-archive-keyring.gpg

APT preferences:
  60-nvidia:
    Package: nsight*
    Pin: release l=*Debian*
    Pin-Priority: -1
    
    Package: *
    Pin: release l=NVIDIA CUDA
    Pin-Priority: 600
    
    Package: /nvidia/ /cuda/ /nvcuvid/ /nvctrl/
    Pin: version 550.54.*
    Pin-Priority: 1000

Nvidia offset (under)clock:
  nvidia-settings -a [gpu:0]/GPUGraphicsClockOffsetAllPerformanceLevels=-500

rclone systemd mount as user:
  https://github.com/nilreml/rclone-mount-systemd

(Re)configure time zone:
  dpkg-reconfigure tzdata

Change first day of the week to Monday:
  Add en_GB locale:
    sudo dpkg-reconfigure locales -> add en_GB.UTF-8 -> select/keep default system locale (e.g. en_US)
  Use en_GB locale for time only:
    /etc/default/locale -> LC_TIME="en_GB.UTF-8"
    logout & login

Only for headless systems like containers:
  Keyboard layout:
    apt install/dpkg-reconfigure keyboard-configuration -> 27 43 1

  Locales:
    apt install -y locales
    update-locale "LANG=C.UTF-8"
    export LANG=C.UTF-8

    https://unix.stackexchange.com/questions/87745/what-does-lc-all-c-do/87763#87763
    https://stackoverflow.com/questions/59295250/python-default-locale-unsupported-locale-setting/59676852#59676852

Append system lib path:
  echo "path/to/lib" | sudo tee /etc/ld.so.conf.d/[descriptive_name]
  ldconfig

Git OAuth (when SSH isn't an option):
  apt install -t bookworkm-backports git-credential-oauth
  git credential-oauth configure

Patch local .deb archive:
  dpkg -x your_package_vesion.deb your_package_folder/
  dpkg -e your_package_vesion.deb your_package_folder/DEBIAN
  dpkg -b your_package_folder/ new_package_vesion.deb

Integer scaling:
  xrandr --output HDMI-0 --scale 0.5 --filter nearest

Network diagnostics:
  rpcinfo -p
  netstat -an
  iftop -i [if]

Find links:
  find . -type l -ls      # all symlinks
  find -L . -type l -ls   # broken symlinks
  find -type f -links +1  # hardlinks (in addition to filename itself)

Find empty folders:
  find . -type d -empty   # -delete

Find largest folders/files:
  du -ah | sort -hr | head -n 20

Show folder sizes counting hardlinks only once:
  du -hc --max-depth=0 [dir1] [dir2] [...]

Fix mouse scroll not working while moving in Virtualbox:
  apt install imwheel
  autostart -> imwheel

Switch between libinput and evdev input drivers:
  sudo apt install xserver-xorg-input-evdev
  sudo apt remove xserver-xorg-input-libinput xserver-xorg-input-all