The idea is to decouple Tomcat and QDC installation to make it easy to upgrade Tomcat in future with below steps.
1. Create symbolic link to tomcat installation directory as below and use the link in configurations.
ln -s apache-tomcat-7.0.94 tomcat
2. Create new Catalina Base directory, copy/sync necessary files from tomcat installation directory and update tomcat startup script
mkdir -p /usr/local/qdc/tomcat-qdc/{bin,conf,logs,temp,webapps,work}
cp -p /usr/local/qdc/tomcat/bin/setenv.sh /usr/local/qdc/tomcat-qdc/bin/
cp -rp /usr/local/qdc/tomcat/conf/ /usr/local/qdc/tomcat-qdc/conf/
cp -rp /usr/local/qdc/tomcat/webapps/* /usr/local/qdc/tomcat-qdc/webapps/
3. Update CATALINA_HOME in startup script with new base directory
