PM2 is a free and open-source process manager for Node.js applications. It is used to monitor the Node.js application and keep it alive 24/7. It allows you to start, stop, and restart the Node.js application via the command line.
PM2 also offers a web-based dashboard that allows you to monitor your Node.js application in real time via a web browser. It is used in a production environment to manage multiple Node.js applications. It offers a rich set of features including real-time logs, email and slack notifications, custom metrics, issues and exception tracking, deployment reporting, and more.
In this post, we will show you how to monitor the Node.js application using the PM2 dashboard.
Prerequisites
- A fresh Arch Linux server on the Atlantic.Net Cloud Platform
- A root password configured on your server
Step 1 – Create Atlantic.Net Cloud Server
First, log in to your Atlantic.Net Cloud Server. Create a new server, choosing Arch Linux as the operating system with at least 2GB RAM. Connect to your Cloud Server via SSH and log in using the credentials highlighted at the top of the page.
Step 2 – Configure Repository
By default, the default repository is outdated in Arch Linux, so you will need to modify the default mirror list. You can do it by editing the mirror list configuration file:
nano /etc/pacman.d/mirrorlist
Remove all lines and add the following lines:
## Score: 0.7, United States Server = http://mirror.us.leaseweb.net/archlinux/$repo/os/$arch ## Score: 0.8, United States Server = http://lug.mtu.edu/archlinux/$repo/os/$arch Server = http://mirror.nl.leaseweb.net/archlinux/$repo/os/$arch ## Score: 0.9, United Kingdom Server = http://mirror.bytemark.co.uk/archlinux/$repo/os/$arch ## Score: 1.5, United Kingdom Server = http://mirrors.manchester.m247.com/arch-linux/$repo/os/$arch Server = http://archlinux.dcc.fc.up.pt/$repo/os/$arch ## Score: 6.6, United States Server = http://mirror.cs.pitt.edu/archlinux/$repo/os/$arch ## Score: 6.7, United States Server = http://mirrors.acm.wpi.edu/archlinux/$repo/os/$arch ## Score: 6.8, United States Server = http://ftp.osuosl.org/pub/archlinux/$repo/os/$arch ## Score: 7.1, India Server = http://mirror.cse.iitk.ac.in/archlinux/$repo/os/$arch ## Score: 10.1, United States Server = http://mirrors.xmission.com/archlinux/$repo/os/$arch
Save and close the file, then update all the package indexes with the following command:
pacman -Syu
Step 3 – Install Node.js and NPM
By default, both packages are available in the Arch Linux default repository. You can install them with the following command.
pacman -S nodejs npm
After the successful installation, you can verify the Node.js version using the following command.
node --version
You should get the following output.
v19.7.0
Step 4 – Create a Sample Node.js App
Next, you will need to create a sample Node.js application so we can monitor it via PM2.
First, create a project directory for the Node.js application.
mkdir project
Next, change the directory to the Project and create an app.js file.
cd project nano app.js
Add the following code.
const http = require('http');
const hostname = 'localhost';
const port = 3000;
const server = http.createServer((req, res) => {
res.statusCode = 200;
res.setHeader('Content-Type', 'text/plain');
res.end('Your Nodejs App is Working!\n');
});
server.listen(port, hostname, () => {
console.log(`Server running at http://${hostname}:${port}/`);
});
Save and close the when you are done.
Next, install the PM2 using the NPM command.
npm install pm2 -g
Then, start the Node.js application using the following command.
pm2 start app.js
You will get the following output.
-------------
__/\\\\\\\\\\\\\____/\\\\____________/\\\\____/\\\\\\\\\_____
_\/\\\/////////\\\_\/\\\\\\________/\\\\\\__/\\\///////\\\___
_\/\\\_______\/\\\_\/\\\//\\\____/\\\//\\\_\///______\//\\\__
_\/\\\\\\\\\\\\\/__\/\\\\///\\\/\\\/_\/\\\___________/\\\/___
_\/\\\/////////____\/\\\__\///\\\/___\/\\\________/\\\//_____
_\/\\\_____________\/\\\____\///_____\/\\\_____/\\\//________
_\/\\\_____________\/\\\_____________\/\\\___/\\\/___________
_\/\\\_____________\/\\\_____________\/\\\__/\\\\\\\\\\\\\\\_
_\///______________\///______________\///__\///////////////__
Runtime Edition
PM2 is a Production Process Manager for Node.js applications
with a built-in Load Balancer.
Start and Daemonize any application:
$ pm2 start app.js
Load Balance 4 instances of api.js:
$ pm2 start api.js -i 4
Monitor in production:
$ pm2 monitor
Make pm2 auto-boot at server restart:
$ pm2 startup
To go further checkout:
http://pm2.io/
-------------
[PM2] Spawning PM2 daemon with pm2_home=/root/.pm2
[PM2] PM2 Successfully daemonized
[PM2] Starting /root/project/app.js in fork_mode (1 instance)
[PM2] Done.
┌─────┬────────┬─────────────┬─────────┬─────────┬──────────┬────────┬──────┬───────────┬──────────┬──────────┬──────────┬──────────┐
│ id │ name │ namespace │ version │ mode │ pid │ uptime │ ↺ │ status │ cpu │ mem │ user │ watching │
├─────┼────────┼─────────────┼─────────┼─────────┼──────────┼────────┼──────┼───────────┼──────────┼──────────┼──────────┼──────────┤
│ 0 │ app │ default │ N/A │ fork │ 65084 │ 0s │ 0 │ online │ 0% │ 14.0mb │ root │ disabled │
└─────┴────────┴─────────────┴─────────┴─────────┴──────────┴────────┴──────┴───────────┴──────────┴──────────┴──────────┴──────────┘
By default, the Node.js application listens on port 3000. You can check it with the following command.
ss -antpl | grep node
You should see the following output.
LISTEN 0 0 [::1]:3000 *:* users:(("node /root/proj",pid=65084,fd=20))
Step 5 – Monitor Node.js Application Using Using PM2 Dashboard
PM2 provides an advance web-based dashboard that monitors your application in real time via a web browser.
First, go to the PM2 website using the URL http://app.pm2.io/.
Then, sign up and log in to the PM2 web dashboard. You should see the following screen.
Provide your bucket name and click on the Create button. You should see the following screen.
From the above screen, copy and run the following command on your terminal.
pm2 link 30ew4cpwzxopx3v tzc9tp9s2oc0wkf
This will add your Node.js application to the PM2 dashboard.
[PM2 I/O] Using: Public key: tzc9tp9s2oc0wkf | Private key: 30ew4cpwzxopx3v | Machine name: archlinux-74b9 [+] PM2+ activated!
Now, refresh your web browser. You should see the new Node.js application added to the dashboard.
Step 6 – Monitor Node.js Server Resources Using PM2 Monit
PM2 also provides a pm2-server-monit module that allows you to monitor key resources of the Node.js applications.
First, install the pm2-server-monit module with the following command.
pm2 install pm2-server-monit
You will get the following output.
⇆ PM2+ activated | Instance Name: archlinux-74b9 | Dash: https://app.pm2.io/#/r/tzc9tp9s2oc0wkf ┌─────┬─────────────────────┬─────────────┬─────────┬─────────┬──────────┬────────┬──────┬───────────┬──────────┬──────────┬──────────┬──────────┐ │ id │ name │ namespace │ version │ mode │ pid │ uptime │ ↺ │ status │ cpu │ mem │ user │ watching │ ├─────┼─────────────────────┼─────────────┼─────────┼─────────┼──────────┼────────┼──────┼───────────┼──────────┼──────────┼──────────┼──────────┤ │ 0 │ app │ default │ N/A │ fork │ 65084 │ 13m │ 0 │ online │ 0% │ 52.9mb │ root │ disabled │ └─────┴─────────────────────┴─────────────┴─────────┴─────────┴──────────┴────────┴──────┴───────────┴──────────┴──────────┴──────────┴──────────┘ Module ┌────┬──────────────────────────────┬───────────────┬──────────┬──────────┬──────┬──────────┬──────────┬──────────┐ │ id │ module │ version │ pid │ status │ ↺ │ cpu │ mem │ user │ ├────┼──────────────────────────────┼───────────────┼──────────┼──────────┼──────┼──────────┼──────────┼──────────┤ │ 1 │ pm2-server-monit │ 3.0.0 │ 65369 │ online │ 0 │ 0% │ 8.8mb │ root │ └────┴──────────────────────────────┴───────────────┴──────────┴──────────┴──────┴──────────┴──────────┴──────────┘
Next, refresh the PM2 dashboard. You should see Node.js resource usage on the following screen.
If you want to remove your added server from the PM2 dashboard, run the following command.
pm2 unlink
You will get the following output.
[PM2 I/O] Permanently disable agent... [PM2 I/O] Agent interaction ended
Conclusion
In this post, we explained how to monitor the Node.js applications using the PM2 web dashboard. You can now try the PM2 dashboard in the production environment to monitor the Node.js application in real-time. Try the PM2 monitoring server on dedicated server hosting from Atlantic.Net!
