Showing a longer timespan in Munin

Munin 2.0 provides a parameter for specifying how many datapoints to retain at each time resolution. For example:

graph_data_size custom FULL_NB, MULTIPLIER_1 MULTIPLIER_1_NB, ... MULTIPLIER_NMULTIPLIER_N_NB
graph_data_size custom 300, 15 1600, 30 3000

...means "retain 300 datapoints at 1 datapoint per 5 minutes, then retain 1600 datapoints at 1 datapoint per 75 minutes, then retain 3000 datapoints at 1 datapoint per 150 minutes".

See http://munin-monitoring.org/wiki/format-graph_data_size and http://blog.pwkf.org/post/2010/08/Waiting-for-Munin-2.0-Keep-more-data-with-custom-data-retention-plans for more information.

Without nothing anything specifically about Munin: if it's using RRDTool for the graphing backend, it's theoretically possible to change the RRAs to what ever you want. The practicality of doing so depends on exactly what you're trying to find out; other tools used in combination may give you a better overview of what your're trying to find out by going back "more than a year".

Changing The graph_data_size directive has no effect on existing graphs.

The default settings at munin 2.0 is graph_data_size normal that is equivalent to:

graph_data_size custom 576, 6 432, 24 540, 288 450

For example, if you want to modify it to graph_data_size custom 576, 6 576, 24 576, 288 576 You may also want change the existing RRD files:

find /var/lib/munin/ -name "*.rrd" | while read FN ; do 
   rrdtool tune $FN RRA#0:=576 RRA#1:=576 RRA#2:=576 RRA#3:=576 RRA#4:=576 RRA#5:=576 RRA#6:=576 RRA#7:=576 RRA#8:=576 RRA#9:=576 RRA#10:=576 RRA#11:=576
   chown munin.munin $FN
done

Unfortunately the munin-graph does not do anything with these datas. The cgi zooming do.

Okay, this is an outdated question, but I needed it and if I needed it again, I would look here.