SSH Commands Reference¶

This section provides essential SSH commands for managing the brennan.page homelab.

Connection Information¶

Host: 159.203.44.169
User: root
SSH Key: ~/.omg-lol-keys/id_ed25519
Domain: brennan.page

Standard SSH Command Format¶

Basic Command Execution¶

ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "command"

Critical Flags: - -i ~/.omg-lol-keys/id_ed25519 - Specifies the SSH key - -T - Disables pseudo-terminal allocation (prevents hanging) - -o BatchMode=yes - No password prompts, non-interactive mode

Multiple Commands¶

ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  cd /opt/homelab
  ls -la
  df -h
  echo 'Commands completed'
"

Using Here-Document¶

ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 << 'EOF'
  cd /opt/homelab/services
  docker compose ps
  docker stats --no-stream
EOF

Common Operations¶

System Status¶

# System information
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  echo '=== System Info ==='
  hostnamectl
  echo -e '\n=== Memory Usage ==='
  free -h
  echo -e '\n=== Disk Usage ==='
  df -h
  echo -e '\n=== Uptime ==='
  uptime
"

Docker Operations¶

# Check running containers
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "docker ps -a"

# Check Docker stats
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "docker stats --no-stream"

# View container logs
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "docker logs --tail 50 container_name"

# Restart a service
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  cd /opt/homelab/services/servicename
  docker compose restart
"

File System Operations¶

# List directory contents
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "ls -lah /opt/homelab"

# Check if file exists
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "test -f /path/to/file && echo 'exists' || echo 'not found'"

# Create directory
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "mkdir -p /opt/homelab/services/newservice"

# Check disk space
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "df -h /opt/homelab"

Service Deployment¶

# Deploy a new service
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  cd /opt/homelab/services/servicename
  docker compose pull
  docker compose up -d
  docker compose ps
"

File Transfer Operations¶

Upload Files (Local → Server)¶

# Single file
scp -i ~/.omg-lol-keys/id_ed25519 localfile.txt root@159.203.44.169:/opt/homelab/

# Directory (recursive)
scp -r -i ~/.omg-lol-keys/id_ed25519 local-directory/ root@159.203.44.169:/opt/homelab/

# Using rsync (preferred for directories)
rsync -avz --exclude '.git' -e "ssh -i ~/.omg-lol-keys/id_ed25519" \
  ./local-directory/ root@159.203.44.169:/opt/homelab/services/

Download Files (Server → Local)¶

# Single file
scp -i ~/.omg-lol-keys/id_ed25519 root@159.203.44.169:/opt/homelab/file.txt ./

# Directory
scp -r -i ~/.omg-lol-keys/id_ed25519 root@159.203.44.169:/opt/homelab/services/ ./

# Using rsync
rsync -avz -e "ssh -i ~/.omg-lol-keys/id_ed25519" \
  root@159.203.44.169:/opt/homelab/backups/ ./local-backups/

File Editing Workflow¶

❌ NEVER DO THIS (Will Hang)¶

# DON'T use interactive editors over SSH
ssh ... "micro /etc/config.file"
ssh ... "nano /etc/config.file"
ssh ... "vim /etc/config.file"

✅ CORRECT File Editing Workflow¶

Method 1: Download → Edit → Upload

# 1. Download file
scp -i ~/.omg-lol-keys/id_ed25519 root@159.203.44.169:/etc/caddy/Caddyfile ./Caddyfile

# 2. Edit locally
micro ./Caddyfile

# 3. Upload back
scp -i ~/.omg-lol-keys/id_ed25519 ./Caddyfile root@159.203.44.169:/etc/caddy/Caddyfile

Method 2: Create Locally, Upload, Move

# 1. Create file locally
cat > docker-compose.yml << 'EOF'
version: '3.8'
services:
  app:
    image: nginx:latest
EOF

# 2. Upload to server
scp -i ~/.omg-lol-keys/id_ed25519 docker-compose.yml root@159.203.44.169:/opt/homelab/services/app/

# 3. Verify upload
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "cat /opt/homelab/services/app/docker-compose.yml"

Method 3: Use echo/cat for Small Changes

# For simple config additions
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  echo 'new configuration line' >> /etc/config.file
"

# For complete file replacement
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "cat > /path/to/file << 'INNEREOF'
file content here
multiple lines
INNEREOF
"

System Maintenance Commands¶

Update System¶

# Check for updates
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  apt update
  apt list --upgradable
"

# Install updates
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  apt upgrade -y
"

Check Logs¶

# System logs
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "journalctl -n 50 --no-pager"

# SSH authentication logs
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "tail -n 50 /var/log/auth.log"

# Docker logs
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "journalctl -u docker -n 50 --no-pager"

Firewall Management¶

# Check UFW status
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "ufw status numbered"

# Add firewall rule
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  ufw allow 22/tcp comment 'SSH Primary'
  ufw allow 80/tcp comment 'HTTP'
  ufw allow 443/tcp comment 'HTTPS'
"

Debugging & Troubleshooting¶

Check Service Response¶

# Test HTTP/HTTPS endpoints
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  curl -I http://localhost:80
  curl -I https://brennan.page
"

# Check port listening
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  netstat -tulpn | grep ':80\|:443\|:22'
"

Verify Docker Compose Files¶

# Validate docker-compose.yml syntax
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  cd /opt/homelab/services/servicename
  docker compose config
"

Check Process and Resource Usage¶

# Top processes
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "ps aux --sort=-%mem | head -n 10"

# Disk usage by directory
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "du -sh /opt/homelab/* | sort -h"

Long-Running Commands¶

Background Processes¶

# Run command in background
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  nohup apt upgrade -y > /tmp/upgrade.log 2>&1 &
  echo 'Upgrade started in background. Check /tmp/upgrade.log'
"

# Using screen for persistent sessions
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  screen -dmS backup bash -c 'tar czf /backup.tar.gz /opt/homelab'
"

# Check screen sessions
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "screen -ls"

Common Pitfalls & Solutions¶

Problem: Command Hangs Indefinitely¶

Solution: Always use -T flag and ensure commands don't wait for input

# ❌ BAD - Will hang
ssh -i ~/.omg-lol-keys/id_ed25519 root@159.203.44.169 "apt install package"

# ✅ GOOD - Won't hang
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "apt install -y package"

Problem: Sudo Asks for Password¶

Solution: Run as root user, or configure passwordless sudo

# Already using root, so no sudo needed
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "command"

Problem: Need to Edit Large Files¶

Solution: Use the download → edit → upload workflow

Problem: Docker Commands Fail¶

Solution: Ensure you're in the correct directory and Docker is running

ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  systemctl status docker
  docker ps
  cd /opt/homelab/services/servicename && docker compose ps
"

Quick Reference: Standard Deployment Workflow¶

# 1. Create/modify files locally
cd ~/homelab/services/newservice
micro docker-compose.yml
micro .env

# 2. Test locally (if possible)
docker compose config

# 3. Upload to server
rsync -avz --exclude '.git' -e "ssh -i ~/.omg-lol-keys/id_ed25519" \
  ~/homelab/services/newservice/ root@159.203.44.169:/opt/homelab/services/newservice/

# 4. Deploy on server
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  cd /opt/homelab/services/newservice
  docker compose pull
  docker compose up -d
  docker compose ps
"

# 5. Verify deployment
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "
  docker ps | grep newservice
  curl -I http://localhost:PORT
"

# 6. Update Caddy if needed
# Download current Caddyfile
scp -i ~/.omg-lol-keys/id_ed25519 root@159.203.44.169:/opt/homelab/caddy/Caddyfile ./Caddyfile

# Edit locally
micro Caddyfile

# Upload
scp -i ~/.omg-lol-keys/id_ed25519 ./Caddyfile root@159.203.44.169:/opt/homelab/caddy/Caddyfile

# Reload Caddy
ssh -i ~/.omg-lol-keys/id_ed25519 -T -o BatchMode=yes root@159.203.44.169 "docker exec caddy caddy reload --config /etc/caddy/Caddyfile"

Security Reminders¶

NEVER disable UFW port 22 while connected via SSH
ALWAYS use -T and -o BatchMode=yes for non-interactive operations
NEVER commit SSH keys or passwords to git
ALWAYS test firewall rules in a safe order
ALWAYS keep local backups before making server changes

Emergency Access¶

If SSH becomes unresponsive or you get locked out:

Use DigitalOcean Console (via web dashboard)
Navigate to Droplet → Access → Launch Console
Login with root credentials
Fix UFW/SSH configuration
Test SSH access before closing console

Additional Resources¶

Server IP: 159.203.44.169
Domain: brennan.page
SSH Key: ~/.omg-lol-keys/id_ed25519
Remote base directory: /opt/homelab/
Local repository: ~/homelab/

Last Updated: 2026-01-16