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General

Installing/Updating​

To get started, just rip the .iso and boot. Make sure all the settings in BIOS force UEFI boot (hardware needs to be compatible as well). You might need a hardwired internet connection. Run:

pacman -S archinstall

And then run archinstall. This is the closest you will get to a guided OS installation with Arch. Alternatively you can manually install with the official installation guide.

To update:

pacman -Syu

You can also check if you need to restart with:

checkservices

Or just compare the version of the kernel installed vs the version running:

pacman -Q linux
uname -a

If the kernels don't match, you need to reboot.

Useful Commands​

Delete all empty folders:

find . -empty -type d -delete

Packages to get started (check arch-wiki too)​

  • cronie / fcron: Cron jobs, for automating stuff or running scripts every given time. To add/edit/remove jobs:
  • crontabs -e
  • micro: Basically the easiest text editor to use with a mouse. All commands are the same as in the OS. EG, ctrl + c is copy, ctrl + v is paste, ctrl + s is save, ctrl + q is quit, etc.
  • nano: Another simple text editor
  • docker: Container driver. Used in conjunction the orchestration tool, docker-compose. Docker Documentation.
  • git: GIT cli client
  • gnome: Desktop Environment. Also check gnome-extras, gnome-shell-extensions.
  • nftables: Firewall rules. Good idea to replace iptables as they are slowly getting deprecated.
  • vnstat: Network traffic monitor
  • wireshark-cli: Packet sniffer. Use with termshark.
  • lf: 'list-files' ... basically ranger.

Default console text editor​

Edit .bashsrc and .bash_profile

Add:

~/.bashrc OR ~/.bash_profile
export EDITOR = [text_editor] #---this goes to bashrc
export VISUAL = [text_editor] #---this goes to bash_profile

If using different shell usually it's the same files to the corresponding shell, eg, for zsh it's .zshrc and .zprofile

Change Default Shell​

List all available shells:

chsh -l

Change:

chsh -s /path/to/shell

ZSH​

Zsh is the superior shell, so use this instead of bash. All plugins and customizations for zsh happen in the .zshrc file in your home directory.

To highlight folders:​

~/.zshrc
if [ -x /usr/bin/dircolors ]; then
    test -r ~/.dircolors && eval "$(dircolors -b ~/.dircolors)" || eval "$(dircolors -b)"
    alias ls='ls --color=auto'
    #alias dir='dir --color=auto'
    #alias vdir='vdir --color=auto'

    alias grep='grep --color=auto'
    alias fgrep='fgrep --color=auto'
    alias egrep='egrep --color=auto'
fi

For shell suggestions​

Install zsh-autosuggestions and source to the .zshrc file.

For syntax highlighting​

Install zsh-syntax-highlighting and source to the .zshrc file.

For amazing cat​

Install bat and then replace cat with alias in the .zshrc file:

alias cat=batcat

In some distros it's simply bat, in some other distros it might be batcat.

To change the default prompt look​

Add the following to .zshrc:

PROMPT="%F{red}%n%f %~ > "

You can customize the prompt to your liking.

Disabling system suspend​

When using a device as e.g a server, suspending might not be needed or it could even be undesired. To configure system sleep states:

/etc/systemd/sleep.conf.d/disable-suspend.conf
[Sleep]
AllowSuspend=no
AllowHibernation=no
AllowSuspendThenHibernate=no
AllowHybridSleep=no

VMs​

First you need the QEMU server, which is the backend for the VMs, the libvirt manager, and optionally the cockpit web interface.

pacman -S qemu-full libvirt virt-manager cockpit cockpit-machines

You need to also enable/start libvirtd.

For cockpit you might need dnsmasq for DCHP for the VMs

pacman -S dnsmasq
Enable/Start dnsmasq

For simpler VM frontend you can use Gnome Boxes which is included with the gnome-extra package.

pacman -S gnome-extra

Software for TPM emulator. Needed for Windows 11.

pacman -S swtpm

For Windows 11​

  1. Download Win11 iso.
  2. Open gnome boxes.
  3. Start a new VM from local files.
  4. Edit memory to at least 4GB.
  5. Edit storage to at least 100GB.
  6. Edit configuration file to enable TPM. Under add:
<tpm model="tpm-crb">
    <backend type="emulator" version="2.0"/>
</tpm>

Save and start the VM.

In Windows 11 installation, to skip internet, hit Shift + F10 to bring up the console and type OOBE\BYPASSNRO and restart. Remember to disconnect the host from the internet so no internet passes through to the guest OS.

GUI / CLI Boot​

You can swap between using a desktop environment or just CLI. To force CLI:

systemctl set-default multi-user.target

To force Desktop Environment:

systemctl set-default graphical.target

Generate Keys​

You can use the openssl command to generate key together with rand. Optionally, you can pass as flags the format you want and the number of digits.

For base64 and 60 digits key:

openssl rand -base64 60

For hexadecimal and 32 digits key:

openssl rand -hex 32

Faillock​

After 3 attempts of sudo the accounts is locked. Check first the failed attempts with faillock and make sure it's actually you. Then you can reset the account fails with:

faillock --user <user> --reset

Archiving and Compression​

Archivers are used to put multiple files into a single file. Compressors are used to reduce the size of a file. These two tools are used together usually when packaging applications or backing up. One combo is tar + gzip. Tar creates and extracts files from archives. Gzip compresses and decompresses the archive files.

Tar flags:

-c Create a new archive. We use this flag whenever we need to create a new archive. -z Use gzip compression. When we specify this flag, it means that archive will be created using gzip compression. -v Provide verbose output. Providing the -v flag shows details of the files compressed. -f Archive file name. Archive file names are mapped using the -f flag. -x Extract from a compressed file. We use this flag when files need to be extracted from an archive.

Creating an archive and compressing it:

tar -czf example_archive.tar.gz /path/to/files

Extracting an archive (remember the -z flag if it's compressed):

tar -xzf example_archive.tar.gz

One can use the -C to specific location of extraction:

tar -xzf example_archive.tar.gz -C /path/to/extraction

Password Store​

pass is a unix password manager. It stores the passwords in a gpg file and uses git to sync.

You need to generate a gpg key to initialize pass:

pass init <your_public_gpg_key>

You can then initialize git for pass store:

pass git init

You can use normal git commands to view history, push, pull and sync your passwords across devices.

To add an existing password:

pass insert github

Where github is any password you want to add. pass is using normal files to save your passwords so you can nest them in folders.

pass insert websites/github

You can see all the stored passwords by running pass.

To generate a new password:

pass generate github

To show a password:

pass show websites/github

If you want to add an url, an email, or any data to a password, you can add it as metadata on the password file:

pass edit websites/github
------------------------------------
random_password
email: [email protected]
URL: https://eelslap.com/

Cryptography​

Generating a new gpg key:

gpg --gen-key

You can check the public id of your key by:

gpg -K

To access and edit the key, copy the ID and:

gpg --edit-key <key_public_id>

You can also access the key with your email:

gpg --edit-key [email protected]

By default, gpg keys expire, but you change that by editing your key and then, in the gpg prompt run expire and follow the prompt.

If you want to change the password of your key, enter again the edit-key menu, run passwd and again, follow the prompt.

You can find additional commands in the edit-key menu by running help.

When moving your key to different machine, remember that you need both your private and public keys. This especially needed with Password Store since it uses your gpg keys to encrypt your password.

Create a temp folder:

mkdir exported_keys
cd exported_keys

Create an export of your public key:

gpg --output --public.gpg --armor --export [email protected]

Create an export of your private key as well. You will be prompted to type your key password:

gpg --output --private.gpg --armor --export-secret-key [email protected]

Transfer the files via scp to the other machine. cd to that folder and import the keys. Start with the private one: gpg --import private.gpg enter your key password, and then import the public key: gpg --import public.gpg

Finally, you will need to max the trust level of the public key for it to work properly. Edit the key, run trust and select 5 in the trust prompt.

Background Processes and 'Hang-Ups'​

Running processes as background in bash is done by adding the ampersand & symbol at the end of a command. You can investigate the active background jobs by:

jobs

You can also push an actively running command to the background by suspending it with Ctrl + Z and then run bg to activate it in the background.

You can bring a background process to foreground again by:

fg

Nonetheless, most of the processes one wants to run in background are done through SSH. That means that the process should not hang up when we disconnect and continue running in the background. We do that by passing nohup at the beginning of the command. In addition, it is useful to also pass the standard output and errors to a file, and also not wait for any standard input. Example:

nohup myscript.sh >myscript.log 2>&1 </dev/null &
#\__/             \___________/ \__/ \________/ ^
# |                    |          |      |      |
# |                    |          |      |  run in background
# |                    |          |      |
# |                    |          |   don't expect input
# |                    |          |   
# |                    |        redirect stderr to stdout
# |                    |           
# |                    redirect stdout to myscript.log
# |
# keep the command running 
# no matter whether the connection is lost or you logout