Tomcat Web Server

Tomcat is a free and open-source web server. It was developed at Sun Microsystems (an American technology company, currently acquired by Oracle). Tomcat is the implementation of Java EE (Java Enterprise Edition) in the newer version of Jakarta Package (Jakarta EE). It supports Jakarta Servlet, Jakarta Server Page, Jakarta Expression Languages, Jakarta WebSockets, etc. It provides a “JAVA HTTP” web server.

 

What is Tomcat?

Apache Tomcat is an open-source web server and also a servlet container that is developed by the Apache Software Foundation. It helps in implementing the Java serverlets, Java serverpages, and other Java-based web technologies. It allows the developers in running the java applications on a web server. It is widely used for hosting the java applications due to its reliability, scalability and strong performance in handling the dynamic web content.

 

How to Install Apache Tomcat and Setup the Environment?

The following are the steps that helps in guiding how to install the apache tomcat in windows and setup its environment:Step 1: First, you have to download the Windows Service Installer from their official website using the Windows Tomcat Binary Distribution.

Step 2: The following screenshot illustrates on the setup of tomcat, it will go through asking for value definition regarding setup.

Step 3: You need to click on next button.

Step 4: Then agreed for installation.

Step 5: Then next -> next-> Finish.

 

Step 6: Now Your server is running on port “http://localhost/8080″.

Restart or Running of Tomcat Server

If you want to stop the server then you need to go to the folder name “Program Files” like in my system “C:\Program Files\Apache Software Foundation” >> “C:\Program Files\Apache Software Foundation\Tomcat 9.0\bin”.

Step 1: Then go inside bin folder

Step 2: Right click on Tomcat9 and then click on stop and similar you can again re-start from here.

How to install Tomcat Server on Linux? A Step-By-Step Guide

The following steps guides you on how to install the tomcat server on Linux:

Step 1: Install Java (if not already installed) on using the following command in the terminal.

sudo apt update

Step 2: Install the default JDK (Java Development Kit) with the following command execution.

sudo apt install default-jdk

Step 3: Verify whether the Java installation has done successfully or not through the below command.

java -version

Setting up a Tomcat User

The following steps guide you on how to setup the tomcat user:

Step 1: Create a new user with the new user name with useradd command as follows:

 

sudo useradd -r -m -U -d /opt/tomcat -s /bin/false tomcat

Step 2: Downloading the Tomcat package with the below command:

wget -c https://downloads.apache.org/tomcat/tomcat-9/v9.0.87/bin/apache-tomcat-9.0.87.tar.gz

Step 3: After the downloading extract the file with tar command as follows:

sudo tar xf apache-tomcat-9.0.87.tar.gz -C /opt/tomcat

Step 4: Change directory

cd  /opt/tomcat
ls -ls

Steps To Change The Bin Directory

The following steps help in changing the bin directory of tomcat:

Step 1: Change to root user

sudo su

Step 2: Change directory

cd /opt/tomcat/apache-tomcat-9.0.87/bin/

Step 3: Start Tomcat using either of the following commands

sh startup.sh
        OR
./startup.sh

Step 4: Open browser, now server is running on

http://localhost:8080/

Step 5: For stop running server

./shutdown.sh

Advantages Of Apache Tomcat

The following are the advantages of apache tomcat:

• Open Source: Tomcat comes as free to use and with having large community support.

• Light Weight: It requires only fewer resource in compared to full-fledged application servers. It is ideal for the small to medium sized applications.

• High Comptability and Integration: It provides fully compatible with java EE specifications, supporting java servlets JSP and web socket technologies.

• Security and Stability: It provides the security features and regular updates, ensuring a stable and secure production environment.

 

Disadvantages Of Apache Tomcat

The following are the disadvantages of apache tomcat:

• Slower Performance Under Heavy Load: When the server experiences high traffic, Tomcat’s performance may slow down.

• Limited Technical Support: The availability of technical support for Tomcat is limited compared to commercial alternatives.

• LImit Features: It lacks some advanced features that found in the comprehensive application servers, such as built-in enterprise services, advanced clustering and extensive management tools.

• Complex Configuration: While setuping the straightforward, configuring the tomcat for advanced features helps in optimizations.

 

Applications of Apache Tomcat Server

The following are the some of the applications of the tomcat server:

• • Web Hosting for Java Applications:
  • Tomcat is widely used for hosting Java-based applications on the web.
  • It implements the Java Servlet and JavaServer Pages (JSP) specifications.
  • Embedded Servers:
  • Tomcat can be embedded within other applications or services.
  • Developers often use it as an embedded servlet container for lightweight deployments.
  • Commonly used for enterprise applications involving:
  • Java Expression Language
  • Java Servlet
  • Java WebSockets
  • Java Server Pages2
  • Web Applications Deployment:
  • Each web application comprises resources such as HTML with Java code, Server Pages, Java Servlets, libraries, and other items required to execute the program.
  • These web applications are stored in Tomcat’s “webapps” directory as folders or WAR (Web Application Archive) files

   

  Trouble Shooting Issues with Tomcat Server

  The following are the some of the tomcat server trouble shooting issues:

  1. Checking Log Files

  • Action: Review the `catalina.out`, `localhost`, and `manager` log files located in the `logs` directory.
  • Purpose: Logs provide detailed error messages and stack traces that can help identify the root cause of issues, such as configuration errors, deployment problems, or runtime exceptions.

  2. Validating Configuration Files

  • Action: Ensure that the `server.xml`, `web.xml`, and `context.xml` configuration files are correctly formatted and properly configured.
  • Purpose: Misconfigurations in these files can lead to startup failures, incorrect application behavior, or security vulnerabilities. Validate XML syntax and configuration settings to resolve such issues.

  3. Monitoring Resource Usage

  • Action: Use monitoring tools to check CPU, memory, and disk usage on the server running Tomcat.
  • Purpose: High resource usage can cause performance degradation and slow response times. Identifying resource bottlenecks allows for appropriate scaling or optimization measures, such as adjusting JVM settings or load balancing.

  4. Diagnosing Network Issues

  • Action: Test network connectivity and port accessibility using tools like `telnet` or `netstat`.
  • Purpose: Network problems can prevent clients from connecting to the Tomcat server. Ensure that the server is listening on the correct ports and that there are no firewall or security group rules blocking access.