Setup Ubuntu for SSH access from dakdevs' Mac

setup-ssh.sh

#!/usr/bin/env bash
# Setup an Ubuntu machine to be SSH-able from dakdevs' Mac.
# Idempotent: safe to re-run.
#
# Usage (on the Ubuntu machine):
#   curl -fsSL <gist-raw-url> | bash

set -euo pipefail

PUBKEY="ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIEqJZkbO069wsfHTuRDMPLNe8SWozP5Gf/cpTgxT3XI1 dakdevs-mac"

echo "==> Installing openssh-server"
sudo apt-get update -qq
sudo DEBIAN_FRONTEND=noninteractive apt-get install -y openssh-server

echo "==> Enabling and starting ssh service"
sudo systemctl enable --now ssh

echo "==> Authorizing Mac public key for user: $USER"
mkdir -p "$HOME/.ssh"
chmod 700 "$HOME/.ssh"
touch "$HOME/.ssh/authorized_keys"
chmod 600 "$HOME/.ssh/authorized_keys"
if ! grep -qxF "$PUBKEY" "$HOME/.ssh/authorized_keys"; then
  echo "$PUBKEY" >> "$HOME/.ssh/authorized_keys"
  echo "   added key"
else
  echo "   key already present"
fi

echo "==> Opening firewall (if ufw is active)"
if command -v ufw >/dev/null 2>&1 && sudo ufw status | grep -q "Status: active"; then
  sudo ufw allow OpenSSH
else
  echo "   ufw not active — skipping"
fi

IP="$(hostname -I 2>/dev/null | awk '{print $1}')"
HOSTNAME="$(hostname)"
echo ""
echo "Done. Connect from Mac with:"
echo "    ssh ${USER}@${IP}"
echo "or:"
echo "    ssh ${USER}@${HOSTNAME}.local"