I am trying to get an aggregated graph of CPU usage across some servers. I have come up with this so far:
[totals]
update no
contacts no
lb_cpu.graph_title LB Total User CPU
lb_cpu.user.sum lb1.example.com:cpu.user lb2.example.com:cpu.user
Unfortunately graph generation does not work. The logs show this error:
2015/07/22 07:21:15 [RRD ERROR] rrdtool graph did not generate the image (make sure there are data to graph).
2015/07/22 07:21:15 [WARNING] Could not draw graph "/var/cache/munin/www/totals/lb_cpu-day.png": /var/cache/munin/www/totals/lb_cpu-day.png
Can anyone spot what is wrong with my config?
Thanks
Update: I updated my example to reflect what I was REALLY doing - i.e. I was not adding a group to the aggregated node name, and using nodes from another group.