How to install tomcat in rhel 6.3 / centos 6.3

This post will cover installing and basic configuration of apache-tomcat-7.0.30

If you do not already have the Java Development Kit (JDK) installed on your machine, you will need to download and install the required JDK for your platform.

If you do have the JDK installed, you can skip to: Step 2: Download and Install the  apache-tomcat-7.0.30

Step 1: Install the JDK

You can download the latest JDK here: http://www.oracle.com/technetwork/java/javase/downloads/index.html

[root@station1 Downloads]# rpm -ivh jdk-7u7-linux-x64.rpm

-->

[root@station1 Downloads]# JAVA_HOME=/usr/java/jdk1.7.0_07

[root@station1 Downloads]# export JAVA_HOME

[root@station1 Downloads]# PATH=$JAVA_HOME/bin:$PATH

[root@station1 Downloads]# export PATH 

[root@station1 Downloads]# vim /root/.bash_profile

# .bash_profile

# Get the aliases and functions
if [ -f ~/.bashrc ]; then
        . ~/.bashrc
fi

# User specific environment and startup programs
JAVA_HOME=/usr/java/jdk1.7.0_07/
export JAVA_HOME
PATH=$JAVA_HOME/bin:$PATH
export PATH
#PATH=$PATH:$HOME/bin
#export PATH

Restart or logout and login

[root@station1 Downloads]# echo $JAVA_HOME
/usr/java/jdk1.7.0_07/

       Step 2: Download and Unpack apache-tomcat-7.0.30 (or latest)

To download apache-tomcat click here

[root@station1 Downloads]# tar -xzvf apache-tomcat-7.0.30.tar.gz

[root@station1 Downloads]# mv apache-tomcat-7.0.30 /usr/share/

[root@station1 Downloads]# vim /etc/init.d/tomcat

    #!/bin/bash
    # description: Tomcat Start Stop Restart
    # processname: tomcat

    # chkconfig: 234 20 80
    JAVA_HOME=/usr/java/jdk1.7.0_07
    export JAVA_HOME
    PATH=$JAVA_HOME/bin:$PATH
    export PATH
    CATALINA_HOME=/usr/share/apache-tomcat-7.0.30

    case $1 in
    start)
    sh $CATALINA_HOME/bin/startup.sh
    ;;
    stop)
    sh $CATALINA_HOME/bin/shutdown.sh
    ;;
    restart)
    sh $CATALINA_HOME/bin/shutdown.sh
    sh $CATALINA_HOME/bin/startup.sh
    ;;
    esac
    exit 0

[root@station1 ~]# chmod 755 /etc/init.d/tomcat

[root@station1 ~]# chkconfig --add tomcat
[root@station1 ~]# chkconfig --level 234 tomcat on

[root@station1 ~]# chkconfig --list tomcat
tomcat             0:off    1:off    2:on    3:on    4:on    5:off    6:off

[root@station1 ~]# service tomcat stop
Using CATALINA_BASE:   /usr/share/apache-tomcat-7.0.30
Using CATALINA_HOME:   /usr/share/apache-tomcat-7.0.30
Using CATALINA_TMPDIR: /usr/share/apache-tomcat-7.0.30/temp
Using JRE_HOME:        /usr/java/jdk1.7.0_07
Using CLASSPATH:       /usr/share/apache-tomcat-7.0.30/bin/bootstrap.jar:/usr/share/apache-tomcat-7.0.30/bin/tomcat-juli.jar
[root@station1 ~]# service tomcat start
Using CATALINA_BASE:   /usr/share/apache-tomcat-7.0.30
Using CATALINA_HOME:   /usr/share/apache-tomcat-7.0.30
Using CATALINA_TMPDIR: /usr/share/apache-tomcat-7.0.30/temp
Using JRE_HOME:        /usr/java/jdk1.7.0_07
Using CLASSPATH:       /usr/share/apache-tomcat-7.0.30/bin/bootstrap.jar:/usr/share/apache-tomcat-7.0.30/bin/tomcat-juli.jar
[root@station1 ~]# service tomcat restart
Using CATALINA_BASE:   /usr/share/apache-tomcat-7.0.30
Using CATALINA_HOME:   /usr/share/apache-tomcat-7.0.30
Using CATALINA_TMPDIR: /usr/share/apache-tomcat-7.0.30/temp
Using JRE_HOME:        /usr/java/jdk1.7.0_07
Using CLASSPATH:       /usr/share/apache-tomcat-7.0.30/bin/bootstrap.jar:/usr/share/apache-tomcat-7.0.30/bin/tomcat-juli.jar
Using CATALINA_BASE:   /usr/share/apache-tomcat-7.0.30
Using CATALINA_HOME:   /usr/share/apache-tomcat-7.0.30
Using CATALINA_TMPDIR: /usr/share/apache-tomcat-7.0.30/temp
Using JRE_HOME:        /usr/java/jdk1.7.0_07
Using CLASSPATH:       /usr/share/apache-tomcat-7.0.30/bin/bootstrap.jar:/usr/share/apache-tomcat-7.0.30/bin/tomcat-juli.jar

For logs

[root@station1 ~]# less /usr/share/apache-tomcat-7.0.30/logs/catalina.out

We can now access the Tomcat Manager page at

[root@station1 ~]# firefox http://station1.ranjihat.com:8080

Tomcat 7 contains a number of changes that offer finer-grain roles.

For security reasons, no users or passwords are created for the Tomcat manager roles by default. In a production deployment, it is always best to remove the Manager application.

To set roles, user name(s) and password(s), we need to configure the tomcat-users.xml file located at $CATALINA_HOME/conf/tomcat-users.xml.

In the case of our installation, $CATALINA_HOME is located at /usr/share/apache-tomcat-7.0.30.

By default the Tomcat 7 tomcat-users.xml file will have the elements between the and tags commented-out. .

New roles for Tomcat 7 offer finer-grained access and The following roles are now available:

manager-gui
manager-status
manager-jmx
manager-script
admin-gu
admin-script.

We can set the manager-gui role, for example as below

[root@station1 ~]# vim /usr/share/apache-tomcat-7.0.30/conf/tomcat-users.xml

<tomcat-users>
<role rolename="manager-gui"/>  <user username="tomcat" password="secret" roles="manager-gui"/>  </tomcat-users>

Manage Memory Usage Using JAVA_OPTS

 Getting the right heap memory settings for your installation will depend on a number of factors.

For simplicity, we will set our inital heap size, Xms, and our maximum heap size, Xmx, to the same value of 128 Mb

Simliarly, there are several approaches you can take as to where and how you set your JAVA_OPTS

Again, for simplicity, we will add our JAVA_OPTS memory parameters in our Catalina.sh file.

So, open the Catalina.sh file located under /usr/share/apache-tomcat-7.0.29/bin with a text editor or vi.

Since we are using 128 Mb for both initial and maximum heap size, add the following line to Catalina.sh

[root@station1 ~]# vim /usr/share/apache-tomcat-7.0.30/bin/catalina.sh
  1 #!/bin/sh
  2 JAVA_OPTS="-Xms128m -Xmx128m"

 How to Run Tomcat using Minimally Privileged (non-root) Use

In our Tomcat configuration above, we are running Tomcat as Root.

For security reasons, it is always best to run services with the only those privileges that are necessary.

There are some who make a strong case that this is not required, but it's always best to err on the side of caution.

To run Tomcat as non-root user, we need to do the following:

1. Create the group 'tomcat':

[root@station1 ~]# groupadd tomcat

[root@station1 ~]# useradd -s /bin/bash -g tomcat tomcat

Change ownership of the tomcat files to the user tomcat we created above

[root@station1 ~]# chown -Rf tomcat.tomcat /usr/share/apache-tomcat-7.0.30/

Adjust the start/stop service script we created above. In our new script, we need to su to the user tomcat:

 [root@station1 ~]# vim /etc/init.d/tomcat

    #!/bin/bash
    # description: Tomcat Start Stop Restart
    # processname: tomcat

    JAVA_HOME=/usr/java/jdk1.7.0_07
    export JAVA_HOME
    PATH=$JAVA_HOME/bin:$PATH
    export PATH
    CATALINA_HOME=/usr/share/apache-tomcat-7.0.30

    case $1 in
    start)
    /bin/su sh $CATALINA_HOME/bin/startup.sh
    ;;
    stop)
    /bin/su sh $CATALINA_HOME/bin/shutdown.sh
    ;;
    restart)
    /bin/su sh $CATALINA_HOME/bin/shutdown.sh
    /bin/su sh $CATALINA_HOME/bin/startup.sh
    ;;
    esac
    exit 0

               How to Run Tomcat on Port 80 as Non-Root User 

Note: the following applies when you are running Tomcat in "stand alone" mode with Tomcat running under the minimally privileged user Tomcat we created in the previous step.

To run services below port 1024 as a user other than root, you can add the following to your IP tables

iptables -t nat -A PREROUTING -p tcp -m tcp --dport 80 -j REDIRECT --to-ports 8080 iptables -t nat -A PREROUTING -p udp -m udp --dport 80 -j REDIRECT --to-ports 8080

Be sure to save and restart your IP Tables

Running Tomcat behind Apache

As an alternative to running Tomcat on port 80, if you have Apache in front of Tomcat, you can use mod_proxy as well as ajp connector to map your domain to your Tomcat application(s) using an Apache vhost as shown below.

While Tomcat has improved it's 'standalone performance', I still prefer to have Apace in front of it for a number of reasons.

In your Apache config, be sure to set KeepAlive to 'on'. Apache tuning, of course, is a whole subject in itself...

 76 KeepAlive On

VHOST with mod_proxy 

<VirtualHost *:80>
    ServerAdmin tomcat@station1.ranjihat.com
    ServerName station1.ranjihat.com
    ServerAlias www.ranjihat.com 
 
 
    ProxyRequests Off 
    ProxyPreserveHost On 
    <Proxy *> 
       Order allow,deny 
       Allow from all 
    </Proxy> 
 
 
    ProxyPass / http://station1.ranjihat.com:8080/ 
    ProxyPassReverse / http://station1.ranjihat.com:8080/ 
 
 
    ErrorLog logs/station1.ranjihat.com-error_log 
    CustomLog logs/station1.ranjihat.com-access_log common 
 
</VirtualHost>