Apache Tomcat 8 Application Server

Installation Guide

By :

Mohamed Moharam

System Engineer

The Apache Tomcat Server The Apache Tomcat server is an open source, Java-based web application container that was

created to run servlet and JavaServer Pages (JSP) web applications. It was created under the

Apache-Jakarta subproject; however, due to its popularity, it is now hosted as a separate Apache

project, where it is supported and enhanced by a group of volunteers from the open source Java

community. Apache Tomcat is very stable and has all of the features of a commercial web

application container – yet comes under Open Source Apache License. Tomcat also provides

additional functionality that makes it a great choice for developing a complete web application

solution. Some of the additional features provided by Tomcat—other than being open source and

free—include the Tomcat Manager application, specialized realm implementations, and Tomcat

valves.

The Tomcat Directory Structure

The Tomcat installation directory is referred to as CATALINA_HOME. describes the directories

that compose a Tomcat installation. It is assumed that each of these directories is contained

within the

CATALINA_HOME directory.

Directory Contents

/bin

Contains the startup and shutdown scripts for both Windows and Linux. Jar files withclasses required for tomcat to start are also stored here.

/conf

Contains the main configuration files for Tomcat. The two most important are server.xmland the global web.xml.

/lib

Contains the Tomcat Java Archive (jar) files, shared across all Tomcat components. All web applications deployed to Tomcat can access the libraries stored here. This includesthe Servlet API and JSP API libraries.

/logs Contains Tomcat’s log files.

/webapps

The directory where all web applications are deployed, and where you place your WAR file when it is ready for deployment.

/work

Tomcat’s working directory where Tomcat places all servlets that are generated from JSPs. If you want to see exactly how a particular JSP is interpreted, look in this directory.

/tmp

Contain temp filesystems storage

Install JAVA 8 (JDK 8u66) on CentOS.

This article will help you to Install JAVA 8 (JDK 8u66) or update on your system. Read

instruction carefully for downloading java from Linux command line.

Downloading Latest Java Archive

Download latest Java SE Development Kit 8 release from its official download page or use

following commands to download from shell.

For 64Bit

# cd /opt/

# wget --no-cookies --no-check-certificate --header "Cookie:

gpw_e24=http%3A%2F%2Fwww.oracle.com%2F; oraclelicense=accept-

securebackup-cookie" "http://download.oracle.com/otn-

pub/java/jdk/8u66-b17/jdk-8u66-linux-x64.tar.gz"

# tar xzf jdk-8u66-linux-x64.tar.gz

Install Java with Alternatives

After extracting archive file use alternatives command to install it. alternatives command is

available in chkconfig package.

# cd /opt/jdk1.8.0_66/

# alternatives --install /usr/bin/java java /opt/jdk1.8.0_66/bin/java

2

# alternatives --config java

There are 3 programs which provide 'java'.

Selection Command

-----------------------------------------------

+ 2 /opt/jdk1.8.0_66/bin/java

Enter to keep the current selection[+], or type selection number: 2

At this point JAVA 8 has been successfully installed on your system. We also recommend to

setup javac and jar commands path using alternatives

# alternatives --install /usr/bin/jar jar /opt/jdk1.8.0_66/bin/jar 2

# alternatives --install /usr/bin/javac javac

/opt/jdk1.8.0_66/bin/javac 2

# alternatives --set jar /opt/ jdk1.8.0_66/bin/jar

# alternatives --set javac /opt/ jdk1.8.0_66/bin/javac

Check Installed Java Version

Check the installed Java version on your system using following command.

root@tecadmin ~# java -version

java version "1.8.0_66"

Java(TM) SE Runtime Environment (build 1.8.0_66-b17)

Java HotSpot(TM) 64-Bit Server VM (build 25.66-b17, mixed mode)

Configuring Environment Variables

Most of Java based application’s uses environment variables to work. Set the Java environment

variables using following commands

Setup JAVA_HOME Variable

# export JAVA_HOME=/opt/jdk8

Setup JRE_HOME Variable

# export JRE_HOME=/opt/jdk8/jre

Setup PATH Variable

# export PATH=$PATH:/opt/jdk8/bin:/opt/jdk8/jre/bin

Also put all above environment variables in /etc/environment file for auto loading on system

boot.

Step 2: Downloading Tomcat Archive

Download Apache Tomcat 8 archive file using following commands or you can visit Tomcat

8official download page for download most recent available version. After downloading extract

archive file in /opt directory. You may change this location as per your setup.

# cd /opt

# wget http://www.us.apache.org/dist/tomcat/tomcat-

8/v8.0.27/bin/apache-tomcat-8.0.27.tar.gz

# tar xzf apache-tomcat-8.0.27.tar.gz

Step 3: Configure Environment Variables

Before starting Tomcat, configure CATALINA_HOME environment variable in your system

using following commands.

# echo "export CATALINA_HOME=\"/opt/tomcat8\"" >> ~/.bashrc

# source ~/.bashrc

Step 4: Starting Tomcat

Tomcat is very easy to use, There are no need to compile its source. You simple extract the

archive and start the tomcat server. Tomcat by default start on port 8080, So make sure no other

application using the same port.

# cd /opt/apache-tomcat-8.0.27

# ./bin/startup.sh

Step 5: Access Tomcat in Browser

Tomcat server works on port 8080 default. Access tomcat on web browser by connecting your

server on port 8080.

http://localhost:8080

Step 6 : verify Tomcat is running successful

Step 6: Setup User Accounts

Finally we need to create user accounts to secure and access admin/manager pages.

Editconf/tomcat-users.xml file in your editor and paste inside <tomcat-users> </tomcat-

users> tags.

Now you can access the Tomcat Application Server with the username & password to deploy

applications and check server status as you see below .

Deploying WAR Archive

The WAR (Web Archive) file is a single file that contains all web application resources, and can

be deployed directly to Tomcat. The WAR file is actually a zip-compatible archived file . To

deploy a WAR-packaged web application, all you have to do is copy it to the

CATALINA_HOME/webapps directory. Make sure you remove the previously deployed

application’s exploded directory. Upon server startup, Tomcat will pick up the apress.war file and deploy it automatically. When Tomcat is up and running again, you can access the web

application from the browser in the same way as before.

The Second method 1-login to the Tomcat web server using username & password .2- choice

manage applications . 3- the middle you will see war file deploy section 4- choose the war file

5. press deploy now your application have been uploaded remotely and running in the apache

tomcat as you see in the following

(1)

(2)

(3)

(4)

Customizing the Java Virtual Machine

Exploring the java jvm and customize it to enhance application performance in memory and

issues related to garbage collections by controlling the max memory size for the JVM and min

memory for the heap size . by opining /opt/tomcat-server/bin/catalina.sh and modify memory

size as you see in the following

Connection Proxy

Since Tomcat typically listens on port 8080, rather than configure Tomcat on

port 80 for normal HTTP requests, we can use Nginx to proxy those

connections and rewrite the URLs

1- Install epel for nginx packages

2- Create new directory under /etc/nginx as you see below

3- Create new configuration file to to be able to access the server over port 80 instead off

8080 using nginx features as you see and restart the service now you can access it over

port 80 instead of 8080 http://server:80