ISPConfig 3 script to move installation from one server to another

ispconfig-migration.sh

#!/bin/bash
# Migrate ISPConfig 3 installation from one server to another
# This script should run on the final/destination ISPConfig 3 server
# You must first install the same ISPConfig on the destination server
# and make sure to create all the users from the previous installation
# (ISPConfig creates users for each client and web page)
# Tested on ISPConfig version 3.0.5.3
# Created by Jorge Barnaby (@jbarnaby) - March 2014

# EDIT YOUR PREVIOUS ISPCONFIG SERVER HERE
main_server=old-server.domain.com

#common_args='-aPv --delete'
#common_args='-aPv --dry-run'
common_args='-aPv'

www_start="service apache2 start"
www_stop="service apache2 stop"
db_start="service mysql start"
db_stop="service mysql stop"

function db_migration {
  echo "---- Starting DB migration..."
  # Stop Remote and Local MySQL Servers
  ssh $main_server "$db_stop"
  $db_stop

  # Copy MySQL files
  rsync $common_args --compress --delete $main_server:/var/lib/mysql/ /var/lib/mysql

  # Start Remote and Local MySQL Servers
  ssh $main_server "$db_start"
  $db_start

  # TODO:
  # You should update ISPConfig MySQL Password to match your new server's, as it's stored in
  # several ISPConfig files (it's a faster approach than updating the password in all those places)
  # Enter MySQL on the destination server and run:
  # SET PASSWORD FOR 'ispconfig'@'localhost' = PASSWORD('YOUR NEW ISPCONFIG MYSQL PASSWORD'); 
  # You should also make shure all the tables on the destination server are clean:
  # mysqlcheck -A --auto-repair
  echo "---- DB migration done."
}

function www_migration {
  echo "---- Starting WWW migration..."
  $www_stop
  rsync $common_args --compress --delete $main_server:/var/www/ /var/www
  rsync $common_args --compress --delete $main_server:/var/log/ispconfig/httpd/ /var/log/ispconfig/httpd
  $www_start
  echo "---- WWW migration done."
}

function mail_migration {
  echo "---- Starting Mail migration..."
  rsync $common_args --compress --delete $main_server:/var/vmail/ /var/vmail
  rsync $common_args --compress --delete $main_server:/var/log/mail.* /var/log/
  echo "---- Mail migration done."
}

function files_migration {
  echo "---- Starting Files migration..."
  rsync $common_args $main_server:/var/backup/ /var/backup
  # The following files are copied just to have a reference of the previous
  # installation users and groups. You should manually create those users in
  # your new server
  rsync $common_args $main_server:/etc/passwd /root/old-server/
  rsync $common_args $main_server:/etc/group  /root/old-server/
  echo "---- Files migration done."
}

function mailman_migration {
  echo "Starting MailMan Migration..."
  rsync $common_args --compress --delete $main_server:/var/lib/mailman/lists /var/lib/mailman
  rsync $common_args --compress --delete $main_server:/var/lib/mailman/data /var/lib/mailman
  rsync $common_args --compress --delete $main_server:/var/lib/mailman/archives /var/lib/mailman
  # Update / Regenerate aliases
  cd /var/lib/mailman/bin && ./genaliases
  echo "MailMan Migration done."
}

# Execute migrations
www_migration
mail_migration
db_migration
files_migration
mailman_migration

Getting internal server error 500 on all the sites except the control panel itself. It appears to run and act fine. Anything I missed?

I'm sorry, this script is deleting very important files from my webserver. This is not acceptable. So i think the migration Tool is my last chance :-(