So, it appears I am answering my own question.
The non-elegant way of getting it to work is this:
Login as mythtv. Easiest way is to login as your own user,
su - mythtv (default password is mythtv).
su - mythtv
cd /myth/rrd
cp /var/www/rrdtool_*.html .
mkdir rrdtool log png
cd rrdtool
ln -s ../png/CPU-Daily.png cpu-day.png
ln -s ../png/CPU-Monthly.png cpu-month.png
ln -s ../png/CPU-Weekly.png cpu-week.png
ln -s ../png/CPU-Yearly.png cpu-year.png
ln -s ../png/Net-Daily.png eth0-day.png
ln -s ../png/Net-Monthly.png eth0-month.png
ln -s ../png/Net-Weekly.png eth0-week.png
ln -s ../png/Net-Yearly.png eth0-year.png
ln -s ../png/Disk-Daily.png hda-day.png
ln -s ../png/Disk-Monthly.png hda-month.png
ln -s ../png/Disk-Weekly.png hda-week.png
ln -s ../png/Disk-Yearly.png hda-year.png
ln -s ../png/Mem-Daily.png memory-day.png
ln -s ../png/Mem-Monthly.png memory-month.png
ln -s ../png/Mem-Weekly.png memory-week.png
ln -s ../png/Mem-Yearly.png memory-year.png
ln -s ../png/Swap-Daily.png swap-day.png
ln -s ../png/Swap-Monthly.png swap-month.png
ln -s ../png/Swap-Weekly.png swap-week.png
ln -s ../png/Swap-Yearly.png swap-year.png
Now do the following operations as root:
Modify /usr/local/bin/run_rrd and modify it so it looks like this:
#!/bin/sh
# ./run_rrd
cd /usr/local/bin
RRD='CPU Load Mem Swap Net Disk'
DIR='.'
#
for x in $RRD ; do
$DIR/rrd_${x}.pl >& /dev/null
done
#
exit 0
# End
edit root's crontab file (crontab -e) and put this line in there:
*/5 * * * * /usr/local/bin/run_rrd
Add the following link as www-data:
cd /var/www
ln -s /myth/rrd rrd
That's it. You should not have to reboot or restart anything. After about 15 minutes or so, you should start seeing data flow into your graphs.
If you want to make the graphs look a little less squished, you can edit the rrd_tool_*.html files and remove the width and height arguments in front of each of the png files.
Nice thing about this is, with a Dragon2 using SATA drives the drive activity is now captured.