Other Cacti Tips

In RRA:AVERAGE:0.5:1:446400 '1' means that points are averaged from 1 samples, --step 10 given in rrdtool create actually sets the update interval (10 seconds)
You can modify/recreate an RRD from the command line after cacti made one and remove/add AVG/MAX/MIN RRAs. They only help what rrdtool graph can display
Cacti depends on mysql to work, backup your mysql data.
Keep raw data outside of cacti in case you need to recreate your RRDs later.
Look up rrdtool information when in doubt, cacti is just a frontend to rrdtool.
You can create composite graphs from multiple data sources: http://forums.cacti.net/viewtopic.php?p=195379 (for instance, unmonitored power data is meter data minus all monitored items)

In RRA:AVERAGE:0.5:1:446400 '1' means that points are averaged from 1 samples, --step 10 given in rrdtool create actually sets the update interval (10 seconds)