In this tutorial, we'll learn how to setup Monit on Ubuntu 24.02 to montior server health, configure Nginx as a reverse proxy, and secure Monit with HTTPS using Certbot.
Monitoring our Ubuntu 24.02 server is critical to ensure it runs smoothly, efficiently, and securely. Downtime or undetected failures can severely impact service availability. To tackle this, we can set up a lightweight, reliable, and powerful tool called Monit.
Monit is an open-source utility that automatically monitors system processes, files, directories, and services on Unix systems. It can restart crashed services and send alerts when something goes wrong. Here’s how we can set it up step-by-step on our Ubuntu 24.02 server.
Prerequisites
Before starting, make sure our new Ubuntu server is ready. The following components should be installed and configured:
- A Ubuntu 24.04 installed dedicated server or KVM VPS.
- A root user or normal user with administrative privileges.
- A domain name with pointing A record to server.
How to Monitor Your Ubuntu 24.02 Server with Monit and Secure It Using Nginx and SSL (Step-by-Step Guide)
Step 1: Update Our Ubuntu 24.02 Server
Before installing any packages, it’s a best practice to update our system to the latest state:
sudo apt update && sudo apt upgrade -y
This ensures our packages and security patches are current.
Step 2: Install Monit
Monit is available in the default Ubuntu repositories, so installation is straightforward:
sudo apt install monit -y
Once installed, the Monit daemon starts automatically. We can check its status using:
sudo systemctl status monit
Step 3: Enable and Start Monit
To make sure Monit starts at boot:
sudo systemctl enable monit
sudo systemctl start monit
Step 4: Configure Monit for Web Access
Monit comes with a built-in web interface, which we can enable for easier monitoring.
Open the Monit configuration file:
sudo nano /etc/monit/monitrc
Uncomment and edit the following lines:
set httpd port 2812 and
use address 0.0.0.0 # or 127.0.0.1 for local access only
allow admin:monit # username:password for web login
Save and exit the file (Ctrl+O, Enter, Ctrl+X).
Restart Monit to apply changes:
sudo systemctl restart monit
Now we can access the Monit dashboard via:
http://<your-server-ip>:2812
Login using the credentials we defined (admin / monit in the example above).
Step 5: Set Up Email Alerts
To receive notifications when something fails, we need to configure Monit to send email alerts.
In the same /etc/monit/monitrc file, find and update these lines:
set mailserver smtp.gmail.com port 587
username "your-email@gmail.com" password "your-app-password"
using tlsv12
set alert your-email@gmail.com
Replace with actual email and an App Password if using Gmail (due to 2FA).
Save and exit the file.
Restart Monit:
sudo systemctl restart monit
We will now receive alerts when monitored services or resources encounter issues.
Step 6: Monitor Critical Services
Let’s configure Monit to monitor critical services like Nginx, MySQL, or SSH.
Example: Monitor Nginx
Create a config file:
sudo nano /etc/monit/conf-enabled/nginx
Add:
check process nginx with pidfile /run/nginx.pid
start program = "/usr/sbin/service nginx start"
stop program = "/usr/sbin/service nginx stop"
if failed port 80 protocol http then restart
if 5 restarts within 5 cycles then timeout
Save and close.
Check the config syntax:
sudo monit -t
Then reload Monit:
sudo systemctl reload monit
Repeat similar steps to monitor other services (e.g., MySQL, Apache, SSH).
Step 7: Monitor System Resources
Monit can also track CPU, memory, disk usage, and more.
Add this to /etc/monit/monitrc or a separate file in conf-enabled:
check system ubuntu-server
if loadavg (1min) > 2 then alert
if memory usage > 80% then alert
if cpu usage (user) > 70% then alert
if cpu usage (system) > 30% then alert
if cpu usage (wait) > 20% then alert
Reload Monit again:
sudo systemctl reload monit
Step 8: View Monit Status
Use the following command to view all monitored services:
sudo monit status
It gives us a quick overview of what’s running fine and what isn’t.
Step 9: Install and Configure Nginx on Ubuntu 24.02
Nginx is a popular and high-performance web server. We'll start by setting it up.
1. Install Nginx
sudo apt install nginx -y
2. Start and Enable Nginx
sudo systemctl enable nginx
sudo systemctl start nginx
3. Allow Nginx Through the Firewall
sudo ufw allow 'Nginx Full'
sudo ufw reload
We assume UFW (Uncomplicated Firewall) is active. If not, you can enable it using sudo ufw enable.
Step 10: Create a Server Block (Virtual Host)
Let’s say our domain is monitor.example.com.
1. Create a new config file:
sudo nano /etc/nginx/sites-available/monitor.example.com
2. Add this content:
server {
listen 80;
server_name monitor.example.com;
location / {
proxy_pass http://127.0.0.1:2812/;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
}
}
Enable this config:
sudo ln -s /etc/nginx/sites-available/monitor.example.com /etc/nginx/sites-enabled/
sudo nginx -t
sudo systemctl reload nginx
Step 11: Keep Monit Listening Only on localhost
In /etc/monit/monitrc, update:
set httpd port 2812 and
use address 127.0.0.1 # Only allow local access (secure)
allow admin:monit
This ensures Monit is not directly exposed to the internet.
Then restart Monit:
sudo systemctl restart monit
Step 12: Secure Nginx with SSL Using Certbot (Let’s Encrypt)
Let’s Encrypt provides free SSL certificates and Certbot automates the process.
1. Install Certbot and Nginx plugin:
sudo apt install certbot python3-certbot-nginx -y
2. Obtain and install the SSL certificate:
sudo certbot --nginx -d monitor.example.com
Certbot will:
- Obtain SSL certificates
- Update your Nginx config with HTTPS settings
- Set up auto-renewal
3. Test auto-renewal:
sudo certbot renew --dry-run
This ensures our certificate will automatically renew before it expires.
Step 13: Update Monit to Monitor Nginx with HTTPS
If we’ve already added Nginx monitoring (as shown earlier), we can adjust the port/protocol to reflect HTTPS:
check process nginx with pidfile /run/nginx.pid
start program = "/usr/sbin/service nginx start"
stop program = "/usr/sbin/service nginx stop"
if failed port 443 protocol https then restart
if 5 restarts within 5 cycles then timeout
Reload Monit after changes:
sudo systemctl reload monit
Final Thoughts
In this tutorial, we've learnt how to setup Monit on Ubuntu 24.02. Monit is an ideal tool for setting up a lightweight monitoring and alerting system on our Ubuntu 24.02 server. It not only watches over critical services and resources but also takes recovery actions automatically. With web UI and email alerting, we stay informed and in control 24/7 — even when we’re not logged in.
By now, we’ve:
- Installed and configured Monit to monitor our system and services
- Set up Nginx as our web server
- Secured Nginx with Let’s Encrypt SSL using Certbot
- Integrated Nginx with Monit for automatic monitoring and alerting
By implementing Monit, we are actively improving the uptime, stability, and resilience of our infrastructure.
If you're running production workloads or hosting critical services, Monit should be one of the first tools we deploy.
Check out our low cost dedicated server.
