PM2 Cheatsheet

What is PM2?

PM2 (Process Manager 2) is a production-ready process manager for Node.js applications. Keep apps running 24/7 with automatic restarts, load balancing, and zero-downtime deployments.

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📥 PM2 - Install & Version

Install PM2 globally and verify installation.

npm install -g pm2
pm2 -v

When to use

• First-time PM2 setup
• CI/CD agents
• VPS or production servers

🚀 PM2 - Start Application

Start a Node.js application with a custom name.

pm2 start app.js --name my-app

Start with environment variables.

NODE_ENV=production pm2 start app.js --name my-app

🔌 PM2 - Start with Port

Run application on a specific port.

PORT=3000 pm2 start app.js --name my-app

📊 PM2 - List Processes

View all running processes managed by PM2.

pm2 list

ℹ️ PM2 - Process Status & Info

Get detailed information about a specific process.

pm2 show my-app

Includes:

• PID
• Memory usage
• Restart count
• Environment variables

🛑 PM2 - Stop Application

Stop a running process.

pm2 stop my-app

Stop by process ID.

pm2 stop 0

🔄 PM2 - Restart Application

Restart application without downtime (single instance).

pm2 restart my-app

Restart all applications.

pm2 restart all

⚡ PM2 - Reload (Zero Downtime)

Reload application with zero downtime (cluster mode).

pm2 reload my-app

Recommended for

• Production deployments
• API servers
• User-facing services

🗑️ PM2 - Delete Process

Remove application from PM2.

pm2 delete my-app

Delete all processes.

pm2 delete all

📄 PM2 - Logs (All Processes)

View combined logs.

pm2 logs

📝 PM2 - Logs (Single App)

View logs for a specific app.

pm2 logs my-app

🧹 PM2 - Clear Logs

Clear all PM2 logs.

pm2 flush

Useful when

• Disk usage increases
• Logs grow too large

📈 PM2 - Monitor Resources

Live monitoring dashboard.

pm2 monit

Shows:

• CPU usage
• Memory usage
• Restart count

🔀 PM2 - Cluster Mode

Run application in cluster mode using all CPU cores.

pm2 start app.js -i max --name my-app

Run with specific number of instances.

pm2 start app.js -i 4 --name my-app

📦 PM2 - Ecosystem File

Generate ecosystem configuration.

pm2 ecosystem

Start using ecosystem file.

pm2 start ecosystem.config.js

📋 PM2 - Ecosystem Example

module.exports = {
  apps: [
    {
      name: "my-app",
      script: "app.js",
      instances: "max",
      exec_mode: "cluster",
      env: {
        NODE_ENV: "development"
      },
      env_production: {
        NODE_ENV: "production"
      }
    }
  ]
}

🌍 PM2 - Start with Environment

Start application using production environment.

pm2 start ecosystem.config.js --env production

🔁 PM2 - Auto Restart on Crash

PM2 automatically restarts crashed applications.

To limit restarts:

pm2 start app.js --max-restarts 5

💾 PM2 - Save Process List

Save current process list for startup.

pm2 save

🚀 PM2 - Startup on Server Boot

Generate startup script.

pm2 startup

Follow the command output and then run:

pm2 save

👀 PM2 - Reload on File Change (Dev)

Watch files and restart on change.

pm2 start app.js --watch

Not recommended for production

🔧 PM2 - Update Environment Variables

Reload app after updating env variables.

pm2 restart my-app --update-env

🔄 PM2 - Reset Restart Counter

Reset restart count for an app.

pm2 reset my-app

❌ PM2 - Uninstall PM2

Remove PM2 globally.

npm uninstall -g pm2

✅ PM2 - Common Production Checklist

• Use cluster mode
• Enable startup script
• Save process list
• Use ecosystem file
• Monitor memory usage
• Rotate logs externally
• Reload instead of restart