RRD Specify RRA and Resolution

Don't leave it up to RRD Tool to select the RRA and resolution to use.
Specify the RRA and resolution to use per the graph havg value.
Fix the RRD RRA’s to collect the correct amount of data for the Previous Period view for each resolution.

Applied when RRD's are created.

RRA:AVERAGE:0.5:1:1200         = 20 hours of 1 minute data
RRA:AVERAGE:0.5:5:720           = 2.5 days of 5 minute data
RRA:AVERAGE:0.5:60:1860       = 2.5 months of 1 hour data
RRA:AVERAGE:0.5:1440:3652   = 10 years of 1 day data