Note: I have no familiarity with munin, but I have enough familiarity with RRDTool to tell you that my gut feeling is that what you're suffering from is the underlying RRDTool bits.
The munin run interval almost certainly matches the interval set in all of the underlying RRDs (called "step") -- meaning,
) was run when you set up munin with an interval value of 3540 seconds (60*59). See here:
So, you would need to delete and recreate all of your RRD files to contain the new interval value (3540 seconds).
I imagine "rolling back" to 5 minutes would work, except that some internal munin bits may be wedged/confused -- or possibly some data was inserted into the RRDs which in turn confused the hell out of
You have to remember that with RRDs, any time you update/insert some data, it affects all of the existing data in the file (for lack of better explanation). So a single mistake can, in some circumstances, cause permanent damage.
Changing the step with existing data is a pain in the ass. Prepare to become confused:
This, as well as many other reasons, is why I avoid anything that uses RRDTool like the plague. I know you don't need opinions right now in the middle of trying to troubleshoot something, but RRDTool is just a complete utter nightmare on numerous levels. Don't ask me for other software to use -- I end up developing all my own stuff and using a different storage mechanism solely to stay away from RRDTool.--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.