homelab/scripts/linux_setup-README.md

linux_setup.sh

A single idempotent Bash script that takes a fresh Debian/Ubuntu or RHEL/Fedora/CentOS install and prepares it for development work — essential packages, Python, SSH (server + keypair), Docker, common CLI tools, and a few sane baseline system settings.

Written after doing this setup manually one too many times across VMs and fresh installs — this is meant to be the one command that gets a box from "just installed" to "ready to work on" in a couple of minutes.

What it does

Step	Installs / Configures
Essential packages	curl, wget, git, vim, htop, jq, tar, gzip, unzip, build tools, ca-certificates, gnupg
Python	Python 3, pip (upgraded), venv, virtualenv, pipenv
SSH	OpenSSH client + server, enabled and started via systemctl, ~/.ssh created with 700 permissions
SSH key	Generates an ed25519 keypair (~/.ssh/id_ed25519) if one doesn't already exist, prints the public key at the end for easy copying into GitHub/GitLab
Docker	Docker CE, CLI, containerd, Buildx and Compose plugins from Docker's official repo — verified with a hello-world test run after install
Dev tools	tree, net-tools, ping utilities, ncdu, btop
System config	UTC timezone (if not already set), helpful ls aliases in /etc/bash.bashrc, basic firewall (UFW or firewalld): deny incoming except SSH, allow all outgoing

Every step checks whether its target is already installed/configured before doing anything — safe to re-run after a partial failure or to pick up a newly-added tool without redoing the whole setup.

Supported distributions

Detected automatically via /etc/os-release (with fallbacks to /etc/redhat-release / /etc/debian_version):

• Debian family — Debian, Ubuntu, and anything with ID_LIKE=debian
• RHEL family — RHEL, CentOS, Fedora, and anything with ID_LIKE matching rhel or fedora

Unrecognized distros aren't blocked outright — the script warns and proceeds, but package-manager-specific steps (install, cache update) will no-op rather than guess at a package manager.

Usage

sudo ./linux_setup.sh

Must run as root (sudo) — it's installing system packages, writing to /etc, and enabling system services.

Skip specific steps

sudo ./linux_setup.sh --skip-docker --skip-dev-tools

Flag	Skips
--skip-packages	Essential package install + cache update
--skip-python	Python 3 / pip / virtualenv / pipenv
--skip-ssh	OpenSSH install + service enable/start
--skip-ssh-key	SSH keypair generation
--skip-docker	Docker CE install
--skip-dev-tools	tree, ncdu, btop, etc.
--skip-system	Timezone, shell aliases, firewall config
--log-file FILE	Custom log path (default: /tmp/linux_setup_<timestamp>.log)

Every step is logged to both the terminal (with color-coded INFO/SUCCESS/WARNING/ERROR prefixes) and the log file, so a run can be reviewed after the fact without needing to have watched it live.

Worth knowing before running

• Firewall is enabled by default (--skip-system to avoid this) — UFW/firewalld gets set to deny all incoming except SSH. Safe for a fresh server, but worth knowing if the box already has other services listening that you don't want cut off.
• Adds the invoking user to the docker group (Debian family only, via SUDO_USER) — meaning that user can run docker without sudo after their next login. This is the standard Docker convention, but is effectively root-equivalent access to the host, worth being aware of on a shared machine.
• SSH key has no passphrase (-N "" in the ssh-keygen call) — intentional for unattended/scripted setup, but means anyone with filesystem access to ~/.ssh/id_ed25519 can use it directly. Fine for a personal dev box; worth adding a passphrase manually afterward on anything more sensitive.
• Individual step failures are logged as warnings and the script continues rather than aborting — check the log file after a run to confirm nothing silently failed.

License

MIT (or update to match the rest of the repo's licensing)