Deploying a Java Application on a VPS: My Experience with Complete Setup

As a developer, deploying a Java application to a VPS (Virtual Private Server) for the first time can seem daunting. However, with a bit of patience and a step-by-step approach, the process becomes quite straightforward. Recently, I had the opportunity to deploy a Java application on an Ubuntu VPS, complete with MySQL integration, SSL certificates, and a custom subdomain. Here’s my experience.

I am Using putty client for access the VPS.

Step 1: Accessing Your VPS with PuTTY or Terminal

To begin, I used PuTTY, a lightweight and easy-to-use SSH client for Windows, to connect to my VPS.

• Download and Install PuTTY.

Visit PuTTY's official website and download the installer for Windows.

Complete the installation process.

• Connect to the VPS.

Open PuTTY.

In the Host Name (or IP address) field, I entered the IP address of my VPS.

Set the Port to 22 (default SSH port).

Click Open to initiate the connection.

• Login to the VPS.

Once the terminal opened, I entered the username root and the password provided by my VPS provider.

On the first connection, PuTTY displayed a security alert to confirm the server’s authenticity. I clicked Yes to proceed.

Step 2: Installing Java (JDK) on the VPS

The first requirement for running a Java application is installing the Java Development Kit (JDK). I chose OpenJDK 17 for my setup. Here's how I did it.

• Update the Package List:

I always ensure my VPS is up-to-date before installing any software.

sudo apt update
sudo apt upgrade -y        

sudo :- This allows you to run the command as a superuser (administrator), granting you the necessary permissions to manage system files and configurations.

apt: The package management tool for Debian-based systems like Ubuntu. It is used to handle software packages.

update: This command updates the local package index (a database of available packages and their versions) from the repositories listed in the /etc/apt/sources.list file.

upgrade: This command upgrades all installed packages to their latest versions, based on the updated package index.

• Install OpenJDK:

To install JDK, I ran the following command.

sudo apt install openjdk-17-jdk -y        

• Verify the Installation:

I checked the installed Java version to confirm the installation.

java -version        

The output displayed the installed version, confirming success.

Step 3: Installing MySQL for the Database

Since my application required a database, I installed MySQL on the VPS.

• Install MySQL.

sudo apt install mysql-server -y        

• During the setup:

I set a strong root password.

Removed anonymous users and test databases.

Disabled remote root login for added security.

• Log in to MySQL.

I accessed MySQL to configure the database.

sudo mysql -u root -p        

• Create a Database and User.

Inside the MySQL shell, I created a database and user.

CREATE DATABASE myappdb;
CREATE USER 'myappuser'@'%' IDENTIFIED BY 'securepassword';
GRANT ALL PRIVILEGES ON myappdb.* TO 'myappuser'@'%';
FLUSH PRIVILEGES;
EXIT;        

If you are not using Hibernate Create tables as per the requirement.

Step 4: Building the Java JAR for Production

On my local machine, I used Maven to package my application into a JAR file:

• Build the JAR,

I navigated to my project folder and ran.

mvn clean package        

This created a file named myapp-1.0-SNAPSHOT.jar in the target folder.

• Upload the JAR to the VPS

Using PSCP (PuTTY Secure Copy), I uploaded the JAR file to the VPS.

pscp target/myapp-1.0-SNAPSHOT.jar root@your_vps_ip:/opt/myapp.jar        

Step 5: Configuring a Subdomain

To make my application accessible through a custom URL like app.mydomain.com, I set up a subdomain.

1. Configure DNS Records,

In my domain registrar’s dashboard, I created.

An A Record pointing to the VPS IPv4 address.

An AAAA Record pointing to the VPS IPv6 address.

Step 6: Installing SSL Certificates

To secure my application, I used Certbot to install SSL certificates.

• Install Certbot and Nginx.

sudo apt install certbot python3-certbot-nginx nginx -y        

• Configure Nginx,

I created an Nginx configuration file

sudo nano /etc/nginx/sites-available/myapp        

• Added this configuration

I am not adding my Configurations here because security Purposes.

server {
    listen 80;
    server_name app.mydomain.com;

    location / {
        proxy_pass https://localhost:8080;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
    }
}        

This are dummy configurations change as per your setup.

• Enabled the configuration

sudo ln -s /etc/nginx/sites-available/myapp /etc/nginx/sites-enabled/
sudo nginx -t
sudo systemctl restart nginx        

• Install SSL

sudo certbot --nginx -d app.mydomain.com        

Step 7: Creating a Systemd Service for the JAR

To ensure my application starts automatically and runs in the background, I created a systemd service.

• Create the Service File,

I opened a new service file

sudo nano /etc/systemd/system/myapp.service        

• Added this configuration

[Unit]
Description=My Java Application
After=network.target

[Service]
User=root
ExecStart=/usr/bin/java -jar /opt/myapp.jar
Restart=always
Environment=SPRING_PROFILES_ACTIVE=prod

[Install]
WantedBy=multi-user.target        

• Enable and Start the Service,

I enabled and started the service

sudo systemctl daemon-reload
sudo systemctl enable myapp
sudo systemctl start myapp
sudo systemctl status myapp        

Step 8: Testing the Deployment

Finally, I opened https://app.mydomain.com in my browser, and my application was live!

Conclusion

Deploying a Java application on a VPS was an enriching experience. From using PuTTY to install software, managing databases, and setting up SSL certificates to running my application as a service, every step taught me something new. I hope my experience helps you deploy your application successfully. Happy coding! ??