Tomcat and Apache
This document describes the steps needed to install Apache Tomcat. It also optionally describes how to integrate Tomcat with the Apache Web Server, and how to configure MySQL to work with Tomcat Servlets and JSPs.
Contents
Installation
Install and configure Apache as in the LAMP tutorial. You may install PHP and MySQL at this time if you want them. Install tomcat[broken link: package not found].
Configuring Tomcat
Edit /etc/conf.d/tomcat
. Replace the line
TOMCAT_JAVA_HOME=/usr/lib/jvm/java-1.6.0-openjdk \
with this one (assuming that /opt/java
is your JAVA_HOME):
TOMCAT_JAVA_HOME=/opt/java \
THE FOLLOWING SHOULD NO LONGER BE NEEDED
Edit /etc/conf.d/tomcat
. Change CATALINA_USER to some user that suites your system (like "nobody")
modprobe capability
Now add capabilities to modules in /etc/rc.conf
.
Also you may have to edit /etc/rc.d/tomcat
to change the java home for jsvc. In the "start" section you have change this line:
-home /usr/lib/jvm/java-1.6.0-openjdk \
with this one (assuming that /opt/java
is your JAVA_HOME):
-home /opt/java \
Test Tomcat
Run in terminal (as root):
# /etc/rc.d/tomcat start
Notice that you can check the logs in /opt/tomcat/logs/catalina.log
.
Tomcat should be running. Test by visiting http://localhost:8080/ in a web browser. You can browse the JSP and servlet examples if you like.
This is all that is needed to run Tomcat as a stand-alone server. You can add new webapp directories to the /opt/tomcat/webapps
directory. Optionally, if you want to place webapps in a different directory, you can make /opt/tomcat/webapps/
a symbolic link to another directory. For example, if you wanted to place your web applications in /home/httpd/tomcat
run these commands (as root):
# cd /opt/tomcat # mv webapps /home/httpd/tomcat # ln -s /home/httpd/tomcat/webapps webapps
You can also place symbolic links within the webapps directory.
If you wish tomcat to start on bootup:
Edit /opt/tomcat/bin/catalina.sh
and add this line at the top:
JAVA_HOME=/opt/java
This is needed because JAVA_HOME is not set when the daemons are started
Edit /etc/rc.conf
:
DAEMONS=(some daemons now add tomcat)
Or add this line to rc.local
:
/etc/rc.d/tomcat start
Configure Apache
Without mod_jk
If you have mod_proxy installed (default since Apache 2.0) you only need to include two directives in your httpd.conf
file for each web application that you wish to forward to Tomcat 5. For example, to forward an application at context path /myapp:
ProxyPass /myapp http://localhost:8080/myapp ProxyPassReverse /myapp http://localhost:8080/myapp
Note: starting from Apache 2.2 included mod_proxy supports the AJP protocol and so it's a viable alternative to mod_jk (this package). It's far easier to configure in httpd.conf
or inside a <VirtualHost>:
ProxyPass / ajp://127.0.0.1:8009/APPNAME ProxyPassReverse / ajp://127.0.0.1:8009/APPNAME
Instead of / you can map APPNAME to an arbitrary web path. mod_jk (described below) should be used only if its advanced features are needed.
Using mod_jk
There are two ways to install mod_jk: from AUR or from upstream. In the latter case you should copy it to the directory /usr/lib/httpd/modules/
. Then rename the file to mod_jk.so
and set it executable with
# chmod a+x mod_jk.so
Edit /etc/httpd/conf/httpd.conf
Add this line to the end of the LoadModule section:
LoadModule jk_module modules/mod_jk.so
Add these lines below the LoadModule section:
<IfModule jk_module> JkWorkersFile /etc/httpd/conf/workers.properties JkShmFile /var/run/shm.file JkShmSize 1048576 </IfModule>
Create the file /etc/httpd/conf/workers.properties
. It should contain the following:
# Define some properties workers.apache_log=/var/log/httpd/ workers.tomcat_home=/opt/tomcat workers.java_home=/opt/java ps=/ worker.list=worker2 # Define worker's properties worker.worker2.type=ajp13 worker.worker2.host=localhost worker.worker2.port=8009 worker.worker2.mount=/jsp-examples /jsp-examples/*
Start Apache. Run in terminal (as root):
# /etc/rc.d/httpd start
Only run httpd after tomcat is started (EDIT: I'm not sure if this is true, I can restart & start tomcat and apache separately from each other, I will just get a 'Service unavailable' in Apache if I request a .jsp while tomcat is restarting..)
Visit http://localhost/jsp-examples The Tomcat JSP examples should be visible.
If you want to have URLs other than examples map to tomcat, modify the .mount attribute like
worker.worker2.mount=/jsp-examples /jsp-examples/* /someapp /someapp/*
to your workers.properties
file. The someapp
will map http://localhost/someapp/ to /opt/tomcat/webapps/someapp/
as interpreted by tomcat. There are more complex workers.properties configurations; search the website for more info. http://tomcat.apache.org/connectors-doc/reference/workers.html
Configure MySQL
Do this section only if you want to connect to MySQL from within Tomcat or the Java environment in general.
Review the MySQL documentation and download the driver. 3.0 is a good choice: http://www.mysql.com/products/connector-j/
Untar the driver and copy =mysql-connector-java-3.0.11-stable-bin.jar
into /opt/java/jre/lib/ext
tar xfvz mysql-connector-java-3.0.11-stable.tar.gz cp mysql-connector-java-3.0.11-stable/mysql-connector-java-3.0.11-stable-bin.jar /opt/java/jre/lib/ext
Start MySQL if it isn't already running (as root):
# /etc/rc.d/mysqld start
Test that the driver can be loaded:
Save this as ~TestMysql.java
public class TestMysql { public static void main(String[] args) { try { Class.forName("com.mysql.jdbc.Driver").newInstance(); } catch (Exception e) { System.out.println("The driver couldn't be loaded"); return; } System.out.println("The driver was loaded"); } }
Compile the file:
$ javac TestMysql.java
Run the file
$ java -classpath :/opt/java/jre/lib/ext TestMysql
It will output "The driver was loaded" if the driver is available, otherwise "The driver couldn't be loaded"
You should be able to use the driver using DriverManager.getConnection() in Java programs now. It should also automatically be available to Tomcat servlets and JSPs. See The Mysql Connector/J documentation for more information.