How to Update the Node.js Version in a PM2 Instance

Updating the Node.js version in a PM2-managed application requires a few key steps to ensure a smooth transition without losing your process state. Follow these steps to update Node.js while keeping your PM2 processes intact.

Step 1: Save the Current PM2 State

Before updating Node.js, save the current PM2 process list to restore it later. Run:

pm2 save

This ensures that your running applications and their configurations are backed up.

Step 2: Disable PM2 Auto-Start

If PM2 is set up to start automatically on system boot, disable it before updating Node.js:

pm2 unstartup

This prevents conflicts during the update process.

Step 3: Update Node.js

Use a version manager like NVM (Node Version Manager) to update Node.js.

Refer my Blogs to Update / Install

1. Install / Update NVM in Ubuntu
2. Install/ Upgrade Node in Windows

Verify the installation:

node -v

Step 4: Reinstall PM2

Since PM2 is installed globally, updating Node.js may remove it. Reinstall PM2 using:

npm install -g pm2

Step 5: Update PM2

Ensure PM2 is updated to the latest version to avoid compatibility issues:

pm2 update

Step 6: Restore the Previous PM2 State

Reload the saved process list to restore your applications:

pm2 resurrect

Step 7: Re-enable PM2 Auto-Start

If you want PM2 to start automatically on system reboot, reconfigure it with:

pm2 startup

Follow the on-screen instructions to complete the setup.

Step 8: Reload Applications with the New Node.js Version

Finally, reload your applications with the updated environment variables:

pm2 reload <app-name or index> --update-env

Conclusion

By following these steps, you can seamlessly update your Node.js version while ensuring that your PM2-managed applications continue running smoothly.

Let me know if you need further clarification! 🚀

Originally published at https://blog.udhay.dev on Feb 21, 2025.