New Virtual Machine Server Setup Checklist

I use a lot of checklists -- here is one of mine for setting up a new Linux virtual machine server. The commands are written for Ubuntu/Debian-based systems.

System Updates

Update Package Lists and Upgrade System

First, let's update the package lists and upgrade existing packages:

sudo apt update
sudo apt upgrade

• apt update: Updates the package list/index files from repositories
• apt upgrade: Actually upgrades the installed packages to their latest versions

Docker Installation

The Docker commands below are for Ubuntu only. For Debian, follow the separate official Debian installation guide instead.

1. Remove Conflicting Packages

for pkg in docker.io docker-doc docker-compose docker-compose-v2 podman-docker containerd runc; do sudo apt-get remove $pkg; done

2. Set up Docker Repository

# Add Docker's official GPG key:
sudo apt-get update
sudo apt-get install ca-certificates curl
sudo install -m 0755 -d /etc/apt/keyrings
sudo curl -fsSL https://download.docker.com/linux/ubuntu/gpg -o /etc/apt/keyrings/docker.asc
sudo chmod a+r /etc/apt/keyrings/docker.asc

# Add the repository to Apt sources:
echo \
  "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu \
  $(. /etc/os-release && echo "$VERSION_CODENAME") stable" | \
  sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
sudo apt-get update

3. Install Docker Engine

sudo apt-get install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin

4. Configure Docker to Start on Boot

sudo systemctl enable docker.service
sudo systemctl enable containerd.service

Change Hostname

To permanently change your server's hostname:

sudo hostnamectl set-hostname <<your-new-hostname>>

And update /etc/hosts to reflect the new hostname:

sudo nano /etc/hosts
# Add/update the line:
127.0.0.1 <<your-new-hostname>>

User Management

Create New User with Sudo Privileges

# Create new user
sudo adduser <<new-username>>

# Add to sudo group
sudo usermod -aG sudo <<new-username>>

# Add to docker group
sudo usermod -aG docker <<new-username>>

Essential CLI Tools Installation

Install Homebrew

Login as your new user above first, as you can't install homebrew as root.

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

Follow the installer's printed Next steps to add brew to your shell before continuing.

Install Micro Editor

sudo apt install micro

Install Lazydocker and Lazygit

brew install jesseduffield/lazydocker/lazydocker
brew install lazygit

SSH Server Configuration

1. Generate SSH Key Pair (on your local machine)

ssh-keygen -t ed25519 -C "[email protected]"

2. Add SSH Keys

For the new user:

# Create .ssh directory
sudo mkdir -p /home/<<new-username>>/.ssh
sudo chown <<new-username>>:<<new-username>> /home/<<new-username>>/.ssh
sudo chmod 700 /home/<<new-username>>/.ssh

# Copy root's authorized_keys to new user (if exists)
if sudo test -f /root/.ssh/authorized_keys; then
    sudo cp /root/.ssh/authorized_keys /home/<<new-username>>/.ssh/
    sudo chown <<new-username>>:<<new-username>> /home/<<new-username>>/.ssh/authorized_keys
    sudo chmod 600 /home/<<new-username>>/.ssh/authorized_keys
fi

# Or manually add your public key if needed
# echo "your-public-key" | sudo tee -a /home/<<new-username>>/.ssh/authorized_keys

3. Test Key Login, Then Configure SSH Server

Keep the current session open. From a new terminal on your local machine, confirm that the new user can log in using a key, without falling back to a password:

ssh -o PreferredAuthentications=publickey <<new-username>>@<<server-ip>>

In that new session, confirm sudo -v succeeds. Only then disable root/password login by editing /etc/ssh/sshd_config:

sudo nano /etc/ssh/sshd_config

Add/modify these important settings:

PermitRootLogin no
PasswordAuthentication no
PubkeyAuthentication yes
MaxAuthTries 10

OpenSSH generally uses the first value it reads: settings included earlier from /etc/ssh/sshd_config.d/*.conf may take precedence over the main file. Check the effective settings with sudo sshd -T and adjust the earlier setting if needed.

4. Restart SSH Service

Validate first, and restart only if validation succeeds:

sudo sshd -t && sudo systemctl restart ssh

Repeat the key-only login check in another terminal before closing the existing sessions.

Security Recommendations

• Always keep your system updated
• Don't allow SSH logins via password
• Consider using UFW (Uncomplicated Firewall) to manage incoming connections; allow your SSH port before enabling it (sudo ufw allow OpenSSH for the default port, then sudo ufw enable)
• Docker-published ports bypass normal UFW rules, so UFW alone does not control access to them

Remember to test SSH access with your new user before closing your current session to ensure you haven't locked yourself out of the server.