Changes
removed /etc/init.d/vz update-cron part (not implemented anymore)
rrd_path=/var/lib/rrd
www_path=/var/www/html/traf
# Clear out the old index, otherwise you end up with a repeating index. This would also be a good place to put a header.
rm ${www_path}/index.html
cd $rrd_path
*/30 * * * * root /path/to/script/vz_direct_traffic_render
EOF
To check the output of this later run: