Problem in Thumbnail generation and JVM settings

JAVA_OPTS configuration can be seen in /opt/alfresco/tomcat/scripts
Inside this we will have the file name by name ctl.sh.
To make the thumbnails to work we should add -Djava.awt.headless=true in ctl.sh file

#!/bin/sh

CATALINA_HOME=/opt/alfresco/tomcat
TOMCAT_BINDIR=/opt/alfresco/tomcat/bin
JRE_HOME=/opt/alfresco/java
CATALINA_PID=/opt/alfresco/tomcat/temp/catalina.pid
export CATALINA_PID
TOMCAT_STATUS=""
ERROR=0
PID=""

start_tomcat() {
is_tomcat_running
RUNNING=$?
if [ $RUNNING -eq 1 ]; then
echo "$0 $ARG: tomcat (pid $PID) already running"
else
rm -f $CATALINA_PID
export JAVA_OPTS="-Xms512m -Xmx1024m -Xss1024k -XX:MaxPermSize=256m -XX:NewSize=256m -XX:+UseConcMarkSweepGC -Dalfresco.home=/opt/alfresco -Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.ssl=false -Djava.awt.headless=true"
export JAVA_HOME=$JRE_HOME
$TOMCAT_BINDIR/startup.sh
if [ $? -eq 0 ]; then
echo "$0 $ARG: tomcat started"
else
echo "$0 $ARG: tomcat could not be started"
ERROR=1
fi
fi
}

daemon_tomcat() {
export JAVA_OPTS="-Xms512m -Xmx1024m -Xss1024k -XX:MaxPermSize=256m -XX:NewSize=256m -XX:+UseConcMarkSweepGC -Dalfresco.home=/opt/alfresco -Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.ssl=false -Djava.awt.headless=true"
export JAVA_HOME=$JRE_HOME
$TOMCAT_BINDIR/catalina.sh run
}

stop_tomcat() {
$TOMCAT_BINDIR/shutdown.sh 300 -force
if [ $? -eq 0 ]; then
echo "$0 $ARG: tomcat stopped"
if [ -f $CATALINA_PID ] ; then
rm $CATALINA_PID
fi
sleep 3
else
echo "$0 $ARG: tomcat could not be stopped"
ERROR=2
fi
}

get_pid() {
PID=""
PIDFILE=$1
# check for pidfile
if [ -f $PIDFILE ] ; then
PID=`cat $PIDFILE`
fi
}

get_tomcat_pid() {
get_pid $CATALINA_PID
if [ ! $PID ]; then
return
fi
}

is_service_running() {
PID=$1
if [ "x$PID" != "x" ] && kill -0 $PID 2>/dev/null ; then
RUNNING=1
else
RUNNING=0
fi
return $RUNNING
}

is_tomcat_running() {
get_tomcat_pid
is_service_running $PID
RUNNING=$?
if [ $RUNNING -eq 0 ]; then
TOMCAT_STATUS="tomcat not running"
else
TOMCAT_STATUS="tomcat already running"
fi
return $RUNNING
}

if [ "x$1" = "xstart" ]; then
start_tomcat
sleep 2
elif [ "x$1" = "xdaemon" ]; then
daemon_tomcat
elif [ "x$1" = "xstop" ]; then
stop_tomcat
sleep 2
elif [ "x$1" = "xstatus" ]; then
is_tomcat_running
echo $TOMCAT_STATUS
fi

exit $ERROR