SKILL.md
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Disable root login & password auth
vim /etc/ssh/sshd_config
PermitRootLogin no
PasswordAuthentication no
systemctl restart sshd
## Firewall (UFW)
ufw default deny incoming
ufw default allow outgoing
ufw allow ssh
ufw allow 80/tcp
ufw allow 443/tcp
ufw enable
ufw status
## Nginx Configuration
/etc/nginx/sites-available/myapp
server {
listen 80;
server_name example.com www.example.com;
location / {
proxy_pass http://localhost:3000;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection 'upgrade';
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_cache_bypass $http_upgrade;
}
}
Enable site
ln -s /etc/nginx/sites-available/myapp /etc/nginx/sites-enabled/
nginx -t && systemctl reload nginx
## SSL with Let's Encrypt
apt install certbot python3-certbot-nginx -y
certbot --nginx -d example.com -d www.example.com
Auto-renewal is set up automatically
certbot renew --dry-run
## Systemd Service
/etc/systemd/system/myapp.service
[Unit]
Description=My App
After=network.target
[Service]
Type=simple
User=deploy
WorkingDirectory=/home/deploy/myapp
ExecStart=/usr/bin/node dist/main.js
Restart=on-failure
Environment=NODE_ENV=production
[Install]
WantedBy=multi-user.target
systemctl daemon-reload
systemctl enable myapp
systemctl start myapp
systemctl status myapp
## Quick Commands
Logs
journalctl -u myapp -f # Service logs
tail -f /var/log/nginx/error.log
Disk
df -h # Disk usage
du -sh /var/* # Directory sizes
Process
htop # Process monitor
lsof -i :3000 # What uses port