12. Systemd Services: Creating Custom System Daemons with Automatic Restart & Logging • DevOps, Docker & Cloud VPS Deployment Mastery • Rishabh Ki Kaksha

DevOps, Docker & Cloud VPS Deployment Mastery › 12. Systemd Services: Creating Custom System Daemons with Automatic Restart & Logging

40 mins

← Prev Next →

Course Syllabus

Module 1: Linux System Administration & Kernel Performance Tuning

01. Linux OS Architecture: Kernel vs User Space, System Calls & Process Management (ps, top, htop) 02. Linux File Permissions (chmod, chown, SUID/SGID) & Sticky Bits Security 03. Networking & Diagnostics: netstat, ss, lsof, tcpdump, curl, dig & DNS Resolution

Part 1: Linux & Docker Containerization

Module 2: Containerization with Docker & Multi-Stage Builds

04. Docker Architecture: Namespaces, Cgroups, UnionFS & Docker Engine Internals 05. Dockerfile Optimization: Layer Caching, Non-Root Users & Ultra-Light Alpine Multi-Stage Builds 06. Docker Compose: Multi-Container Networking, Persistent Volumes & Environment Config 07. Docker Production Security: Read-Only Root FS, Capabilities Drop & Container Scanning

Part 2: Nginx, SSL, PM2 & Automated CI/CD

Module 3: Nginx Reverse Proxy, SSL Automation & Security Hardening

08. Nginx Masterclass: Event-Driven Non-Blocking Architecture vs Apache Multi-Threaded 09. Nginx as Reverse Proxy, Load Balancer (upstream) & Gzip/Brotli Compression Config 10. SSL/TLS Automation with Certbot Let's Encrypt, HTTP/2 & Strict-Transport-Security (HSTS) 11. Nginx Rate Limiting (limit_req), DDoS Mitigation & Security Headers Injection

Module 4: Process Management with PM2 & Systemd Services

12. Systemd Services: Creating Custom System Daemons with Automatic Restart & Logging 13. PM2 Enterprise Process Manager: Cluster Mode, Ecosystem Config & Graceful Reloads 14. Log Management & Rotation: logrotate, journalctl & Centralized Syslog Streaming

Module 5: CI/CD Automation with GitHub Actions & Zero-Downtime Deployments

15. CI/CD Foundations: Building Automated Test & Build Pipelines with GitHub Actions 16. Automated SSH Deployments: Self-Hosted Runners, Deploy Keys & Zero-Downtime Atomic Symlinks 17. Blue-Green & Canary Deployment Strategies on Cloud VPS Infrastructure

Module 6: Cloud VPS Production Hardening, Firewall (UFW) & Backups

18. Cloud VPS Hardening: Non-Root Sudo Users, SSH Key-Only Auth, Fail2ban & UFW Firewall Rules 19. Automated Database & Media Backups to Cloud Storage (AWS S3 / Cloudflare R2 / MinIO) 20. Server Health Monitoring & Alerting: Uptime Kuma, Netdata, Prometheus & Telegram Bot Webhooks

Interactive Lesson Studio

# 12. Systemd Services: Creating Custom System Daemons with Automatic Restart & Logging

> DevOps & Cloud VPS Notes by Rishabh - Topic 12

---

### 1. Creating Production Daemon Unit (`/etc/systemd/system/node-api.service`) ⚙️

```ini
[Unit]
Description=High Scale Node.js Microservice
After=network.target mysql.service

[Service]
Type=simple
User=www-data
Group=www-data
WorkingDirectory=/var/www/node-api
ExecStart=/usr/bin/node dist/main.js
Restart=always
RestartSec=5s
Environment=NODE_ENV=production PORT=3001
LimitNOFILE=65535

[Install]
WantedBy=multi-user.target
```

---

### 2. Managing Systemd Service Lifecycle

```bash
# Reload daemon files:
systemctl daemon-reload

# Enable on server reboot and start immediately:
systemctl enable --now node-api

# View live real-time logs:
journalctl -u node-api -f -n 100
```

---

### 3. Master Comparison Matrix

---

### 4. Interview Ke 3 Sawal Is Topic Se

1. **`WantedBy=multi-user.target` ka kya matlab hai?** -> Server standard multi-user boot runlevel par aate hi service automatically start ho jayegi.
2. **`journalctl --vacuum-time=7d` command kya karti hai?** -> 7 din se purane systemd journal logs ko safely purge karke disk space free karti hai.
3. **`Type=simple` vs `Type=forking` me kya difference hai?** -> `simple` me `ExecStart` process main daemon hota hai; `forking` me process background me daemon fork karke parent exit ho jata hai.

---
**Next Topic:** 13. PM2 Enterprise Process Manager: Cluster Mode, Ecosystem Config & Graceful Reloads

Loading lesson content...

Python 3.12

Full IDE

Live Execution Terminal

Click "Execute Live" to run code.
                

Lesson Mastery AI Quiz

AI Doubt Solver

CERTIFICATE OF COMPLETION

Rishabh Gehlot

PHP 8+ & Laravel 11 Master Track