I’m spent about 6 hours total working on getting multiple instance of Tomcat to run on Ubuntu and finally wrote some scripts that I’d like to share with folks. These scripts do the following:

1. Setup the box to host multiple instances (JVMs) running tomcat

This process cleans the old layout and sets up a new layout that allows for multiple instances. This includes a number of “instances” directories in /var/lib/tomcat5.5, /etc/defaults/tomat5.5 (a new directory) and /var/log/tomcat5.5.

2. Create new instances

This allows you to setup a new instance quickly. It creates all the necessary directories and also installs the new instance into the init scripts an run levels.

Things the scripts don’t do:

– Setup multiple mod_jk configurations and apache virtual hosts
– Any SSL or security management

Here’s how to use the scripts:

1. First make sure you have Java and Tomcat installed!

bash$ sudo apt-get install sun-java6-jdk tomcat5.5

2. Grab ALL of the scripts and place them in some directory (anywhere is fine)

3. Run the multiple-instances.sh script as root from the directory you put it in

bash$ sudo ./multiple-instances.sh

4. Run the new-instance.sh script to create a new instance

bash$ new-instance.sh <instance-name>

5. Configure the new server by editing the files in /var/lib/tomcat5.5/instances/<instance-name> (mainly conf/server.xml)

6. Make sure each instance has a unique port for everything including the AJP, all listeners and the container

7. Fire it up!

bash$ sudo /etc/init.d/tomcat5.5_<instance-name> start

8. Check the logs in /var/log/tomcat5.5/instances/<instance-name>/catalina.out

Due to security considerations, I’ve included the scripts inline. Any comments are welcome:

multiple-instances.sh

#!/bin/bash

# Verify we are root
if [ "$USER" != "root" ]; then
  echo "You must run this script as root"
  exit 1
fi

# Shutdown any running instace
if ! /etc/init.d/tomcat5.5 stop; then
  echo "Unable to stop the running tomcat instance. Please stop it before running this script."
  exit 1
fi

# Copy over the tomcat.sh file before we change directories
if [ ! -f tomcat.sh ]; then
  echo "The tomcat.sh file is missing. It must be in the current directory so it can be placed"
  echo "into the new layout"
  exit 1
fi
cp tomcat.sh /etc/tomcat5.5
chmod go-wx /etc/tomcat5.5/tomcat.sh

# Now, head out and clean up
if ! cd /var/lib/tomcat5.5; then
  echo "You must first install tomcat from the apt repository"
  exit 1
fi

# Make the instances layout
mkdir instances
chown -R tomcat55:nogroup instances
chmod -R o-rwx instances
chmod -R g+w instances

# Clean up old layout
rm work
rm -rf webapps
rmdir temp
rmdir shared/classes
rmdir shared/lib
rmdir shared
rm logs
rm -rf conf

cd /usr/share/tomcat5.5
rm conf
rm logs
rm shared
rm temp
rm work

# Clean up defaults for the template script
cd /etc/default/
mv tomcat5.5 tomcat-bak
mkdir -p tomcat5.5/instances tomcat5.5/template
mv tomcat-bak tomcat5.5/template/tomcat5.5
chown -R root:root tomcat5.5
chmod -R go-w tomcat5.5
chmod -R g+r tomcat5.5

# Clean up the logs
cd /var/log/tomcat5.5
mkdir old
mv * old
mkdir instances
chown -R tomcat55:nogroup *
chmod -R o-rwx old instances
chmod -R g+w old instances

# Remove the old init script and turn off all script links for the run levels
rm /etc/init.d/tomcat5.5
update-rc.d -f tomcat5.5 remove

echo "Successfully setup the machine for multiple tomcat instances and cleaned up the single instance layout"

new-instance.sh

#!/bin/bash

if [ "$USER" != "root" ]; then
  echo "You must run this script as root"
  exit 1
fi

if [ $# != 1 ]; then
  echo "Usage: new-instance.sh "
  exit 1
fi

# Setup the instance
cd /var/lib/tomcat5.5/instances
if [ -d $1 ]; then
  echo "Instance $1 already created."
  exit 1
fi
mkdir $1

cd $1
mkdir conf webapps bin temp
if ! cp /etc/tomcat5.5/web.xml conf; then
  echo "Unable to create new instance $1 because /etc/tomcat5.5/web.xml doesn't appear to exist"
  exit 1
fi

if ! cp /etc/tomcat5.5/server.xml conf; then
  echo "Unable to create new instance $1 because /etc/tomcat5.5/server.xml doesn't appear to exist"
  exit 1
fi

if ! sed "s/@INSTANCE_NAME@/$1/g" /etc/tomcat5.5/tomcat.sh > bin/tomcat.sh; then
  echo "Unable to find the custom tomcat.sh file in /etc/tomcat5.5. This file must exist."
  exit 1
fi
chown -R tomcat55:nogroup /var/lib/tomcat5.5/instances/$1
chmod -R o-rwx /var/lib/tomcat5.5/instances/$1
chmod -R g+w /var/lib/tomcat5.5/instances/$1
chmod ug+rx bin/tomcat.sh

# Setup the logs
mkdir /var/log/tomcat5.5/instances/$1
chown -R tomcat55:nogroup /var/log/tomcat5.5/instances/$1
chmod -R o-rwx /var/log/tomcat5.5/instances/$1
chmod -R g+w /var/log/tomcat5.5/instances/$1
ln -s /var/log/tomcat5.5/instances/$1 logs

# Create catalina.policy (for the security manager)
echo "// This file is an example of a policy file. You can edit this file for the specific instance" > conf/catalina.policy.example
echo ""  >> conf/catalina.policy.example
cat /etc/tomcat5.5/policy.d/*.policy >> conf/catalina.policy.example
chown tomcat55:nogroup conf/catalina.policy.example
chmod o-rwx conf/catalina.policy.example
chmod g+w conf/catalina.policy.example

# Setup auto start
ln -s /var/lib/tomcat5.5/instances/$1/bin/tomcat.sh /etc/init.d/tomcat5.5_$1
update-rc.d tomcat5.5_$1 defaults 90

tomcat.sh

#!/bin/sh
#
# /etc/init.d/tomcat5.5 -- startup script for the Tomcat 5 servlet engine
#
# Written by Miquel van Smoorenburg .
# Modified for Debian GNU/Linux	by Ian Murdock .
# Modified for Tomcat by Stefan Gybas .
#
### BEGIN INIT INFO
# Provides:          tomcat
# Required-Start:    $local_fs $remote_fs $network
# Required-Stop:     $local_fs $remote_fs $network
# Should-Start:      $named
# Should-Stop:       $named
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Start Tomcat.
# Description:       Start the Tomcat servlet engine.
### END INIT INFO

set -e

PATH=/bin:/usr/bin:/sbin:/usr/sbin
NAME=tomcat5.5
DESC="Tomcat servlet engine"
DAEMON=/usr/bin/jsvc
CATALINA_HOME=/usr/share/$NAME
INSTANCE_NAME=@INSTANCE_NAME@
DEFAULT=/etc/default/$NAME/instances/$INSTANCE_NAME

. /lib/lsb/init-functions
. /etc/default/rcS

# The following variables can be overwritten in $DEFAULT

# Run Tomcat 5 as this user ID
TOMCAT5_USER=tomcat55

# The first existing directory is used for JAVA_HOME (if JAVA_HOME is not
# defined in $DEFAULT)
JDK_DIRS="/usr/lib/jvm/java-6-sun /usr/lib/jvm/java-1.5.0-sun /usr/lib/j2sdk1.4-sun /usr/lib/j2sdk1.4-blackdown /usr/lib/j2se/1.4 /usr/lib/j2sdk1.5-sun /usr/lib/j2sdk1.3-sun /usr/lib/j2sdk1.3-blackdown /usr/lib/j2sdk1.5-ibm /usr/lib/j2sdk1.4-ibm /usr/lib/jvm/java-gcj /usr/lib/kaffe"

# Directory for per-instance configuration files and webapps
CATALINA_BASE=/var/lib/tomcat5.5/instances/$INSTANCE_NAME

# Use the Java security manager? (yes/no)
TOMCAT5_SECURITY=no

# Timeout in seconds for the shutdown of all webapps
TOMCAT5_SHUTDOWN=30

# End of variables that can be overwritten in $DEFAULT

# overwrite settings from default file
if [ -f "$DEFAULT" ]; then
	. "$DEFAULT"
fi

test -f $DAEMON || exit 0

[ -z "$TOMCAT5_USER" ] && TOMCAT5_USER=tomcat55

# Look for the right JVM to use
for jdir in $JDK_DIRS; do
	if [ -r "$jdir/bin/java" -a -z "${JAVA_HOME}" ]; then
		JAVA_HOME_TMP="$jdir"
		# checks for a real JDK like environment, needed to check if
		# really the java-gcj-compat-dev package is installed
		if [ -r "$jdir/bin/jdb" ]; then
			JAVA_HOME="$JAVA_HOME_TMP"
		fi
	fi
done
export JAVA_HOME

# Set java.awt.headless=true if JAVA_OPTS is not set so the
# Xalan XSL transformer can work without X11 display on JDK 1.4+
# It also looks like the default heap size of 64M is not enough for most cases
# se the maximum heap size is set to 128M
if [ -z "$JAVA_OPTS" ]; then
	JAVA_OPTS="-Djava.awt.headless=true -Xmx128M"
fi

JAVA_OPTS="$JAVA_OPTS -Djava.endorsed.dirs=$CATALINA_HOME/common/endorsed -Dcatalina.base=$CATALINA_BASE -Dcatalina.home=$CATALINA_HOME -Djava.io.tmpdir=$CATALINA_BASE/temp"

# Set the JSP compiler if set in the tomcat5.5.default file
if [ -n "$JSP_COMPILER" ]; then
	JAVA_OPTS="$JAVA_OPTS -Dbuild.compiler=$JSP_COMPILER"
fi

if [ "$TOMCAT5_SECURITY" = "yes" ]; then
	JAVA_OPTS="$JAVA_OPTS -Djava.security.manager -Djava.security.policy=$CATALINA_BASE/conf/catalina.policy"
fi

# juli LogManager disabled if running under libgcj (see bug #395167)
gcj=no
"$JAVA_HOME/bin/java" -version 2>&1 | grep -q "^gij (GNU libgcj)" && gcj=yes
if [ "$gcj" != "yes" ]; then
  JAVA_OPTS="$JAVA_OPTS -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djava.util.logging.config.file=$CATALINA_BASE/conf/logging.properties"
fi

# Define other required variables
CATALINA_PID="/var/run/$NAME-$INSTANCE_NAME.pid"
LOGFILE="$CATALINA_BASE/logs/catalina.out"
BOOTSTRAP_CLASS=org.apache.catalina.startup.Bootstrap
JSVC_CLASSPATH="/usr/share/java/commons-daemon.jar:$CATALINA_HOME/bin/bootstrap.jar"

# Look for Java Secure Sockets Extension (JSSE) JARs
if [ -z "${JSSE_HOME}" -a -r "${JAVA_HOME}/jre/lib/jsse.jar" ]; then
    JSSE_HOME="${JAVA_HOME}/jre/"
fi
export JSSE_HOME

case "$1" in
  start)
	if [ -z "$JAVA_HOME" ]; then
		log_failure_msg "no JDK found - please set JAVA_HOME"
		exit 1
	fi

	if [ ! -d "$CATALINA_BASE/conf" ]; then
		log_failure_msg "invalid CATALINA_BASE specified"
		exit 1
	fi

	log_daemon_msg "Starting $DESC" "$NAME"
	if start-stop-daemon --test --start --pidfile "$CATALINA_PID" 
		--user $TOMCAT5_USER --startas "$JAVA_HOME/bin/java" 
		>/dev/null; then

		# Clean up and set permissions on required files
		rm -rf "$CATALINA_BASE"/temp/*
		chown --dereference "$TOMCAT5_USER" "$CATALINA_BASE/conf" 
			"$CATALINA_BASE/conf/tomcat-users.xml" 
			"$CATALINA_BASE/logs" "$CATALINA_BASE/temp" 
			"$CATALINA_BASE/webapps" "$CATALINA_BASE/work" 
			"$CATALINA_BASE/logs/catalina.out" || true

		$DAEMON -user "$TOMCAT5_USER" -cp "$JSVC_CLASSPATH" 
		    -outfile "$LOGFILE"  -errfile '&1' 
		    -pidfile "$CATALINA_PID" $JAVA_OPTS "$BOOTSTRAP_CLASS"
	else
	        log_progress_msg "(already running)"
	fi
	log_end_msg 0
	;;
  stop)
	log_daemon_msg "Stopping $DESC" "$NAME"
        if start-stop-daemon --test --start --pidfile "$CATALINA_PID" 
		--user "$TOMCAT5_USER" --startas "$JAVA_HOME/bin/java" 
		>/dev/null; then
		log_progress_msg "(not running)"
	else
		$DAEMON -cp "$JSVC_CLASSPATH" -pidfile "$CATALINA_PID" 
		     -stop "$BOOTSTRAP_CLASS"
	fi
	log_end_msg 0
	;;
   status)
        if start-stop-daemon --test --start --pidfile "$CATALINA_PID" 
		--user $TOMCAT5_USER --startas "$JAVA_HOME/bin/java" 
		>/dev/null; then

		if [ -f "$CATALINA_PID" ]; then
		    log_success_msg "$DESC is not running, but pid file exists."
		    exit 1
		else
		    log_success_msg "$DESC is not running."
		    exit 3
		fi
	else
		log_success_msg "$DESC is running with pid `cat $CATALINA_PID`"
		exit 0
	fi
        ;;
  restart|force-reload)
        if start-stop-daemon --test --stop --pidfile "$CATALINA_PID" 
		--user $TOMCAT5_USER --startas "$JAVA_HOME/bin/java" 
		>/dev/null; then
		$0 stop
		sleep 1
	fi
	$0 start
	;;
  try-restart)
        if start-stop-daemon --test --start --pidfile "$CATALINA_PID" 
		--user $TOMCAT5_USER --startas "$JAVA_HOME/bin/java" 
		>/dev/null; then
		$0 start
	fi
        ;;
  *)
	log_success_msg "Usage: $0 {start|stop|restart|try-restart|force-reload|status}"
	exit 1
	;;
esac

exit 0