OK, finally (maybe ;-) )
1) You should don't use the run-parts script before rrdtool.sh command.
Change the line to:
Code:
*/1 * * * * root nice /opt/bin/rrdtool.sh >> /opt/var/log/rrdtool.log 2>&1
2) The script is still run each 5 minute. You must remove the rrdtool.sh call from the "/opt/etc/cron.5mins" directory.