Earlier, Tomcat required a high level of expertise for configuring and administering its services, as only advanced users and developers were able to work it out. With Tomcat’s GUI installer, it has become just a matter of a few commands to administer the server as a system service.

What will we cover

This tutorial will show you how to install apache Tomcat and use it to deploy a basic JSP program. Tomcat requires JRE (Java Runtime Environment) for running java web applications. In case if you are developing a Java application, you will need a full JDK application installed. For this, we will cover the guide only with the JRE only.

Prerequisites

You need to be familiar with the Java and basic Linux command to understand this tutorial better. We assume that you have already installed the JRE (Java Runtime Environment) on your system. You also need to have root privileges for installing Apache Tomcat.

Downloading Tomcat

1. To download the Apache Tomcat, visit the Apache Tomcat home page, where you will see different available versions. Alternatively, you can also use the wget command to get the file. For this guide, we are using Tomcat 9.

2. If you prefer, you can download Tomcat from the homepage. This is shown below:

Extracting The Binary Archive

1. Once the archive binary file is downloaded, you need to copy it to the directory where you want to install the Tomcat server and extract the file there. For example, we will extract the Tomcat tar file into /opt/tomcat. For this, we first need to create a directory ‘tomcat’ inside /opt. Use the following command to create a directory.

Creating a user and group for Tomcat

We will create a non-root user and group for running the Apache Tomcat server. Use the command below for creating the user and group.

The above command will also add a ‘tomcat’ group.

Now we will change the ownership of the tomcat directory to the Tomcat user with the command:

Setting Environment Variables

Tomcat requires certain environment variables to be set for running the startup scripts. Let’s see those variables:

a. CATALINA_HOME: The location of this environment variable is the root directory of Tomcat’s “binary” distribution. In our case, this root directory is /opt/tomcat/apache-tomcat-9.0.43

b. JRE_HOME or JAVA_HOME: These environment variables specify the location of Java Runtime Environment and a JDK location, respectively. If you are specifying both JRE_HOME and JAVA_HOME, then JRE_HOME will be used by default.

To set these variables, open the following file:

Now insert the following lines at the end of this file:

Now save the file and run the below command to apply these changes:

To check if these variables are correctly set, check if the output of the below command is the same as the value for JRE_HOME and CATALINA_HOME:

See the below pictures for reference:

Creating Tomcat service

Now we will create a simple systemd unit file to define our Tomcat service. Create the service with the following instructions:

1. Create a file tomcat.service:

Now put the following content inside it:

Note: Please replace the bolded text with the path of your Tomcat installation.

Now save the file and reload the systemd configuration with the following command
to apply the changes

We are now ready to use the tomcat service. Start the service and enable it to persist the reboot.

Check the status of service; it should show an active running status:

All the above steps are shown below:

Accessing Tomcat in Browser

Now we are ready to test if our tomcat server is correctly installed or not. To check this, open your web browser and browse the addresses:

http://localohost:8080
or
http://system_IP_addr:8080 (To see your system IP, use the ip addr command.)

You would see the default homepage of Apache Tomcat. The following screenshot shows the tomcat homepage:

Deploying a simple JSP application

Now we will deploy a basic JSP application with a Tomcat server.

1. Create a basic JSP application called ‘test.jsp’ inside the directory “/opt/tomcat/apache-tomcat-9.0.43/webapps/ROOT/”:

Note: Again, replace the bolded text with the path of your Tomcat installation.

2. Put the following content inside it:

3. Now again, open the web browser and browse the following address:

http://localhost:8080/test.jsp

This time you should see the following web page:

Conclusion

This tutorial shows how we can install Apache Tomcat from an archive binary file on Fedora Linux. We have learned to install a JSP application with tomcat.

Introduction

Step 1: Update APT

First, as always, update your APT.

Step 2: Check for Tomcat in Repository

Check for the Tomcat server package in the repository. The repository will show you all the latest packages available for download.

Step 3: Download Tomcat

Download the tomcat9 package and the tomcat9 admin package and its dependencies with the following terminal command.

Step 4: Install Apache Tomcat Server

When the download is finished, it will install the Apache Tomcat Server, which will start up automatically. For verification, type the following ss command, which will show you the 8080 open port number, the default open port reserved for Apache Tomcat Server.

Step 5: Change Tomcat Settings

When the Ubuntu OS reboots, the Apache Tomcat Server will start automatically. This program setting can be changed by entering one of the following two commands.

OR

Step 6: Allow Traffic to Port 8080

If firewall ports, specifically UFW, are active on your system, devices that want to connect with the Apache Tomcat Server will have difficulty connecting. To allow traffic from any source to port 8080 of the Tomcat Server, type in the following command.

Step 7: Test Tomcat Server

Now, you may test your Tomcat server. When Tomcat starts running, you can test the program in a web browser. Using the system’s loopback address, you can connect to the Tomcat server by specifying the port with the address in the URL search bar, as follows:

Tomcat is up and running if you see this page, “it works!”.

Step 8: Create User

You should create a user for the Web Application Manager in the Tomcat Server. A new user account must be set up to use the Apache Tomcat Web Application Manager.

Open the tomcat-users.xml file in the Tomcat directory with your favorite text editor.

Step 9: Add Tagged Lines

When the file is opened, add these three tagged lines in the file above the “<” tag. Here, new user with the name “tomcat” has been created with a password set as “pass.” Add your own values as substitution for the username and password.

Save the file and close it. Now, we can move on to accessing the manager application area.

Step 10: Restart Tomcat

Restart the Tomcat Server with the following command.

Step 11: Access Tomcat Application Manager

In order to access the Tomcat server web application manager, enter the URL:  http://127.0.0.1:8080/manager/html into the web browser URL search bar and press enter. Next, enter the credentials that you gave to the new user in Tomcat Server. You should now see the Web Application Manager Window.

Conclusion

The Apache Tomcat Server is a great software program for deploying a Java HTTP server. Setting up Apache Tomcat Server on Ubuntu 20.04 is very easy and does not require complex commands.