Environment

Chapter 2: Environment Setup on Arch Linux

Overview

This chapter covers setting up your Arch Linux environment for optimal bash scripting. We’ll configure the shell, install essential tools, and set up a productive development environment. This is specifically tailored for DevOps, SRE, and SysAdmin workflows.

---

Arch Linux Package Management

Understanding Pacman

Arch Linux uses pacman as its package manager. Understanding pacman is crucial for any Arch Linux system administrator.

# Synchronize database and update system
sudo pacman -Syu

# Install a single package
sudo pacman -S package_name

# Install multiple packages
sudo pacman -S package1 package2 package3

# Search for packages
pacman -Ss search_term
pacman -Qs search_term  # Search installed

# Remove package only
sudo pacman -R package_name

# Remove package and its dependencies
sudo pacman -Rs package_name

# Remove packages that were installed as dependencies but no longer needed
sudo pacman -Rsn $(pacman -Qdtq)

# List packages
pacman -Q                # All installed
pacman -Qi package_name # Package info
pacman -Ql package_name # List files

# Clean cache
sudo pacman -Scc        # Clean all cache

Essential Packages for Bash Scripting

# Core utilities - absolutely essential
sudo pacman -S \
    bash \
    bash-completion \
    coreutils \
    findutils \
    gawk \
    sed \
    grep \
    util-linux \
    procps-ng \
    which \
    tree \
    htop \
    tmux \
    vim \
    nano \
    git \
    curl \
    wget \
    rsync \
    cron \
    logrotate \
    strace \
    lsof \
    net-tools \
    dnsutils \
    inetutils \
    openssh

---

Bash Completion

Installation and Configuration

Bash completion is essential for productivity, especially when working with complex commands like kubectl, docker, and terraform.

# Install bash-completion
sudo pacman -S bash-completion

Configuration

Add to your ~/.bashrc:

# Enable bash completion
if ! shopt -oq posix; then
    if [ -f /usr/share/bash-completion/bash_completion ]; then
        . /usr/share/bash-completion/bash_completion
    elif [ -f /etc/bash_completion ]; then
        . /etc/bash_completion
    fi
fi

# Additional completions for common DevOps tools
# kubectl completion
if command -v kubectl &> /dev/null; then
    source <(kubectl completion bash)
fi

# docker completion
if command -v docker &> /dev/null; then
    source /usr/share/bash-completion/completions/docker
fi

# terraform completion
if command -v terraform &> /dev/null; then
    complete -C terraform terraform
fi

Custom Completions

# Example: Add completion for custom scripts
_complete_myapp() {
    local cur prev
    COMPREPLY=()
    cur="${COMP_WORDS[COMP_CWORD]}"
    prev="${COMP_WORDS[COMP_CWORD-1]}"

    case ${COMP_CWORD} in
        1)
            COMPREPLY=($(compgen -W "start stop restart status logs" -- ${cur}))
            ;;
        2)
            COMPREPLY=($(compgen -W "dev staging production" -- ${cur}))
            ;;
    esac

    return 0
}

complete -F _complete_myapp myapp

---

Environment Configuration

The .bashrc File

Your ~/.bashrc is executed for interactive non-login shells. This is where you configure your daily working environment.

~/.bashrc

#===============================================================================
# HISTORICAL CONFIGURATION
#===============================================================================
# Don't put duplicate lines in history
HISTCONTROL=ignoredups:ignorespace

# Append to history file (don't overwrite)
shopt -s histappend

# History size - important for DevOps work
HISTSIZE=10000
HISTFILESIZE=20000

# Check window size after each command
shopt -s checkwinsize

# Enable color support
export CLICOLOR=1

#==============================================================================
# PROMPT CONFIGURATION
#==============================================================================
# Color prompt with Git branch
parse_git_branch() {
    git branch 2>/dev/null | grep '*' | sed 's/* \(.*\)/ (\1)/'
}

PS1='\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[01;31m\]$(parse_git_branch)\[\033[00m\]\$ '

#==============================================================================
# ALIASES - Essential for DevOps
#==============================================================================
# Safety aliases
alias rm='rm -iv'
alias cp='cp -iv'
alias mv='mv -iv'

# List aliases
alias ll='ls -lah'
alias la='ls -A'
alias l='ls -CF'
alias lr='ls -lahR'     # Recursive list

# Grep with color
alias grep='grep --color=auto'
alias egrep='egrep --color=auto'
alias fgrep='fgrep --color=auto'

# DevOps-specific aliases
alias k='kubectl'
alias kgp='kubectl get pods'
alias kgs='kubectl get services'
alias kgd='kubectl get deployments'
alias kga='kubectl get all'
alias klf='kubectl logs -f'
alias kex='kubectl exec -it'

alias d='docker'
alias dps='docker ps'
alias dpsa='docker ps -a'
alias di='docker images'
alias dex='docker exec -it'
alias dlogs='docker logs -f'

alias tf='terraform'
alias tfp='terraform plan'
alias tfa='terraform apply'
alias tfd='terraform destroy'

# System aliases
alias ports='netstat -tulanp'
alias meminfo='free -m -l -t'
alias diskspace='df -h'
alias folders='du -h --max-depth=1'

#==============================================================================
# FUNCTIONS - Reusable for DevOps
#==============================================================================
# Create directory and cd into it
mkcd() {
    mkdir -p "$1" && cd "$1"
}

# Extract common archive formats
extract() {
    if [ -f "$1" ]; then
        case "$1" in
            *.tar.bz2) tar xjf "$1" ;;
            *.tar.gz) tar xzf "$1" ;;
            *.bz2) bunzip2 "$1" ;;
            *.rar) unrar x "$1" ;;
            *.gz) gunzip "$1" ;;
            *.tar) tar xf "$1" ;;
            *.tbz2) tar xjf "$1" ;;
            *.tgz) tar xzf "$1" ;;
            *.zip) unzip "$1" ;;
            *.Z) uncompress "$1" ;;
            *.7z) 7z x "$1" ;;
            *) echo "'$1' cannot be extracted via extract()" ;;
        esac
    else
        echo "'$1' is not a valid file"
    fi
}

# Quick kubectl context switch
kctx() {
    if [ -z "$1" ]; then
        kubectl config get-contexts
    else
        kubectl config use-context "$1"
    fi
}

# Docker cleanup
dclean() {
    echo "Stopping all containers..."
    docker stop $(docker ps -aq) 2>/dev/null || true
    echo "Removing all containers..."
    docker rm $(docker ps -aq) 2>/dev/null || true
    echo "Removing dangling images..."
    docker image prune -f
    echo "Cleanup complete!"
}

#==============================================================================
# ENVIRONMENT VARIABLES
#==============================================================================
# Editor
export EDITOR=vim
export VISUAL=vim
export PAGER=less

# Less colors
export LESS='-R'

# Language
export LANG=en_US.UTF-8
export LC_ALL=en_US.UTF-8

# PATH additions
export PATH="$HOME/bin:$HOME/.local/bin:$PATH"
export PATH="$HOME/go/bin:$PATH"
# Add Cargo (Rust) if installed
[ -d "$HOME/.cargo/bin" ] && export PATH="$HOME/.cargo/bin:$PATH"
# Add Flutter if installed
[ -d "$HOME/flutter/bin" ] && export PATH="$HOME/flutter/bin:$PATH"

# Kubernetes
export KUBECONFIG="$HOME/.kube/config"

# Docker
export DOCKER_BUILDKIT=1
export COMPOSE_DOCKER_CLI_BUILD=1

The .bash_profile File

For login shells, use ~/.bash_profile:

~/.bash_profile

# Source .bashrc if it exists
if [ -f ~/.bashrc ]; then
    . ~/.bashrc
fi

The .profile File

For broader compatibility:

~/.profile

# Set PATH
export PATH="$HOME/bin:$HOME/.local/bin:$PATH"

# Load .bashrc for interactive shells
if [ -n "$BASH_VERSION" ]; then
    if [ -f "$HOME/.bashrc" ]; then
        . "$HOME/.bashrc"
    fi
fi

---

Shell Options

Important shopt Options

# Enable extended globbing - essential for advanced filename matching
shopt -s extglob

# Case-insensitive globbing
shopt -s nocaseglob

# Null glob expansion - empty if no match
shopt -s nullglob

# Fail on glob expansion errors
shopt -s failglob

# Append to history
shopt -s histappend

# Check window size
shopt -s checkwinsize

# Check current options
shopt

# Check specific option
shopt -q extglob && echo "Enabled" || echo "Disabled"

Set Options

# Common set options
set -e   # Exit on error
set -u   # Exit on undefined variable
set -o pipefail  # Pipeline fails on first error
set -x   # Debug mode (trace)
set -v   # Print input lines

---

Text Editor Setup

Vim Configuration

# Install vim
sudo pacman -S vim

# Create ~/.vimrc with DevOps-friendly settings
cat > ~/.vimrc << 'EOF'
"===============================================================================
" VIM CONFIGURATION FOR DEVOPS
"===============================================================================

" Basic settings
set number
set relativenumber
set tabstop=4
set shiftwidth=4
set expandtab
set autoindent
set smartindent
set wrap
set linebreak

" Search settings
set incsearch
set hlsearch
set ignorecase
set smartcase

" Visual settings
syntax on
colorscheme default

" Key mappings
let mapleader = " "

" Enable mouse support
set mouse=a

" Show line numbers
set number

" Highlight current line
set cursorline

" Better backup settings
set nobackup
set nowritebackup
set noswapfile

" Enable persistent undo
set undofile
set undodir=~/.vim/undodir

" Custom mappings
nnoremap <leader>w :w<CR>
nnoremap <leader>q :q<CR>
nnoremap <leader>h :nohlsearch<CR>

" DevOps-specific
autocmd FileType yaml setlocal ts=2 sts=2 sw=2 expandtab
autocmd FileType json setlocal ts=2 sts=2 sw=2 expandtab
autocmd FileType sh setlocal ts=4 sts=4 sw=4 expandtab
autocmd FileType dockerfile setlocal ts=4 sts=4 sw=4 expandtab
EOF

# Create undodir
mkdir -p ~/.vim/undodir

---

Git Configuration

Git Setup for DevOps

# Install git
sudo pacman -S git

# Configure git
git config --global user.name "Your Name"
git config --global user.email "your.email@example.com"
git config --global core.editor vim
git config --global init.defaultBranch main

# Useful git aliases
git config --global alias.st status
git config --global alias.co checkout
git config --global alias.br branch
git config --global alias.ci commit
git config --global alias.lg "log --oneline --graph --all"
git config --global alias.last "log -1 HEAD"
git config --global alias.unstage "reset HEAD --"

# Color settings
git config --global color.ui auto

# Pull strategy
git config --global pull.rebase false

# Default push
git config --global push.default current

---

Terminal Multiplexer

Tmux Configuration

# Install tmux
sudo pacman -S tmux

# Create ~/.tmux.conf
cat > ~/.tmux.conf << 'EOF'
#===============================================================================
# TMUX CONFIGURATION
#===============================================================================

# Prefix key - use Ctrl+a instead of Ctrl+b
set -g prefix C-a
unbind C-b

# Allow nested tmux sessions
bind-key C-a send-prefix

# Start window numbering at 1
set -g base-index 1
set -g pane-base-index 1

# Status bar
set -g status-interval 5
set -g status-left-length 30
set -g status-right-length 50
set -g status-bg black
set -g status-fg white
set -g status-left "#[fg=green]#S #[fg=blue]• #[fg=white]"
set -g status-right "#[fg=white]%Y-%m-%d %H:%M #[fg=blue]• #[fg=white]"

# Window status
setw -g window-status-format " #I: #W "
setw -g window-status-current-format " #I: #W "
setw -g window-status-current-style fg=green,bg=black

# Mouse support
set -g mouse on

# Better pane splitting
bind-key v split-window -h -c "#{pane_current_path}"
bind-key s split-window -v -c "#{pane_current_path}"

# Pane navigation
bind-key h select-pane -L
bind-key j select-pane -D
bind-key k select-pane -U
bind-key l select-pane -R

# Resize panes
bind-key -r H resize-pane -L 5
bind-key -r J resize-pane -D 5
bind-key -r K resize-pane -U 5
bind-key -r L resize-pane -R 5

# Copy mode
setw -g mode-keys vi
bind-key -T copy-mode-vi v send -X begin-selection
bind-key -T copy-mode-vi y send -X copy-selection-and-cancel

# Reload config
bind-key r source-file ~/.tmux.conf \; display "Config reloaded!"
EOF

---

AUR Helpers

Yay Installation

# Install base-devel (required for building from AUR)
sudo pacman -S --needed base-devel git

# Clone and install yay
git clone https://aur.archlinux.org/yay.git
cd yay
makepkg -si

Using Yay

# Search for packages
yay -Ss package_name

# Install packages
yay -S package_name

# System upgrade (including AUR)
yay -Syu

# Remove package and its dependencies
yay -Rsn package_name

Common AUR Packages for DevOps

# Install common DevOps tools from AUR
yay -S \
    terraform \
    ansible \
    packer \
    kubectl \
    helm \
    docker-compose \
    k9s \
    flux-bin \
    argocd

---

Essential DevOps Tools

Installing Common Tools

# Docker
sudo pacman -S docker docker-compose
sudo systemctl enable docker
sudo systemctl start docker
sudo usermod -aG docker $USER

# Kubernetes tools
sudo pacman -S kubectl

# Terraform
yay -S terraform

# Ansible
sudo pacman -S ansible

# Python and pip
sudo pacman -S python python-pip

# Node.js and npm
sudo pacman -S nodejs npm

# Go
sudo pacman -S go

# AWS CLI
pip install awscli --break-system-packages

# GCP CLI
yay -S google-cloud-sdk

# Azure CLI
yay -S azure-cli

---

Directory Structure

Recommended Project Structure

~/bash-scripts/
├── bin/                    # Executable scripts
│   ├── deploy.sh
│   ├── backup.sh
│   └── monitor.sh
├── lib/                    # Shared libraries
│   ├── common.sh
│   ├── utils.sh
│   └── config.sh
├── config/                 # Configuration files
│   ├── app.conf
│   └── .env
├── logs/                   # Log files
│   └── .gitkeep
├── tests/                  # Test scripts
│   └── test_utils.sh
├── docs/                   # Documentation
├── README.md              # Project README
├── Makefile              # Build automation
└── .gitignore           # Git ignore rules

Create the Structure

mkdir -p ~/bash-scripts/{bin,lib,config,logs,tests,docs}
touch ~/bash-scripts/logs/.gitkeep

---

Environment Variables for Scripting

Essential Variables

# Add to ~/.bashrc

# History configuration
export HISTSIZE=10000
export HISTFILESIZE=20000
export HISTCONTROL=ignoredups:ignorespace

# Language
export LANG=en_US.UTF-8
export LC_ALL=en_US.UTF-8

# Editor
export EDITOR=vim
export VISUAL=vim
export PAGER=less

# PATH additions
export PATH="$HOME/bin:$HOME/.local/bin:$PATH"
export PATH="$HOME/go/bin:$PATH"

# Kubernetes
export KUBECONFIG="$HOME/.kube/config"

# Docker
export DOCKER_BUILDKIT=1
export COMPOSE_DOCKER_CLI_BUILD=1

# Go
export GOPATH="$HOME/go"
export PATH="$PATH:$GOPATH/bin"

# AWS
export AWS_DEFAULT_REGION=us-east-1

---

Quick Reference: Arch Linux Commands

┌─────────────────────────────────────────────────────────────────────┐
│                    ARCH LINUX QUICK REFERENCE                         │
└─────────────────────────────────────────────────────────────────────┘

┌──────────────────┬─────────────────────────────────────────────────┐
│ Command          │ Description                                     │
├──────────────────┼─────────────────────────────────────────────────┤
│ pacman -Syu      │ Full system upgrade                             │
│ pacman -S <pkg>  │ Install package                                 │
│ pacman -R <pkg>  │ Remove package                                  │
│ pacman -Qs <pkg> │ Search installed packages                       │
│ pacman -Qdt      │ List orphans (unused dependencies)              │
│ pacman -Qe       │ List explicitly installed packages               │
│ pacman -Qi <pkg> │ Package information                             │
│ pacman -Ql <pkg> │ List package files                             │
│ pacman -Fs <file>│ Find which package provides file                │
│ yay -S <pkg>     │ Install from AUR                                │
│ yay -Syu         │ Full system upgrade (including AUR)             │
│ systemctl         │ Manage systemd services                         │
│ journalctl        │ View system logs                                │
│ hostnamectl       │ System information                              │
│ timedatectl       │ Time and date settings                          │
│ localectl         │ Locale settings                                 │
│ loginctl          │ User session management                         │
└──────────────────┴─────────────────────────────────────────────────┘

---

Testing Your Setup

Verify Bash Version

# Check bash version - should be 5.x on Arch Linux
bash --version

# Verify bash features
echo $BASH_VERSION

Test Completions

# Source bashrc
source ~/.bashrc

# Test completion
sudo pacman -S<tab><tab>
kubectl<tab><tab>
docker<tab><tab>

Test Script Execution

# Create test script
cat > /tmp/test.sh << 'EOF'
#!/bin/bash
# Test script for environment verification

set -euo pipefail

echo "==============================================="
echo "Bash Environment Test"
echo "==============================================="
echo "Bash version: $BASH_VERSION"
echo "Working directory: $(pwd)"
echo "Home directory: $HOME"
echo "User: $USER"
echo "Hostname: $HOSTNAME"
echo "==============================================="

# Test essential commands
echo -n "Testing essential commands: "

commands=("grep" "awk" "sed" "find" "curl" "wget" "git")
all_ok=true

for cmd in "${commands[@]}"; do
    if command -v "$cmd" &> /dev/null; then
        echo -n "✓ "
    else
        echo -n "✗ ($cmd missing) "
        all_ok=false
    fi
done
echo

if [ "$all_ok" = true ]; then
    echo "All essential commands available!"
    exit 0
else
    echo "Some commands are missing. Install them with: sudo pacman -S ..."
    exit 1
fi
EOF

chmod +x /tmp/test.sh
/tmp/test.sh

---

Summary

Your Arch Linux environment is now configured for bash scripting:

• ✅ Pacman and AUR configured
• ✅ Bash completion enabled
• ✅ Custom prompt with Git support
• ✅ Essential DevOps tools installed
• ✅ Text editor configured
• ✅ Git configured
• ✅ Tmux configured
• ✅ Project structure created

---

Exercises

Level 1: Basics

1. Configure your bash environment with aliases for kubectl and docker
2. Install additional tools you need for your daily work
3. Create your project directory structure

Level 2: Intermediate

4. Install and configure tmux with custom settings
5. Set up vim with YAML and Python support
6. Configure kubectl completion

Level 3: Advanced

7. Create a script that auto-installs your preferred environment
8. Set up a custom prompt with Kubernetes context display
9. Configure dotfiles repository for your configuration

---

Next Steps

In the next chapter, we’ll write your first bash script and learn the basic syntax.

---

Previous Chapter: Introduction to Bash Next Chapter: Basic Syntax and First Script