I've been noticing fairly large discrepancies lately with what cnMaestro is reporting for throughput for APs and SMs and what SNMP graph data reports. cnMaestro appears to be severely under reporting throughput.
As an example, here is an MRTG graph taken from data obtained from an AP via SNMP. This AP has a single client on it. That client reported a large download at this same time frame. My graphs of switch ports, backhaul and WAN interfaces all corroborate this graph so I know it to be accurate:
It shows a sustained use around 60 Mbps for 30 minutes.
Here is what cnMaestro showed for that same client:
cnMaestro shows a small peak of use topping out at 28 Mbps for a short period of time. It does not show the 30 minute of sustained 60 Mbps that I know passed through this SM. I've been given the impression before that cnMaestro was off but I never had a prolonged clean graph to prove it.
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Thanks for the question. Can you try viewing the same data with "1 Day" and see if the peaks a much closer to what you expected ?
It seems that the MRTG graph is X-axis is covering approximately a 2 hour window of time and each of it's sample points are roughly one minute apart. Does this seem correct ?
cnMaestro currently has two settings when viewing performance charts data. One setting is for "1 Day" and the other is for "7 Days". When using the 1 day setting, the data points are reported every 5 minutes. When the 7 day setting is used, the 5 minute sample data is aggregated and displayed in 1 hour increments (representing an average of the twelve 5 minute samples).
It's possible that since the data was bursted for 30 minutes, the aggregation at 7 days was not sufficient to catch the peaks. Can you try viewing the same data with "1 Day" and see if the peaks a much closer to what you expected ?
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How do you change to just a 1 day view of the traffic?
When you have clicked on an ePMP AP or SM in the device tree, you can then navigate to the MONITOR --> PERFORMANCE GRAPHS view from the main menu (or alternatively click on the icon highlighted in BLUE near the top of the device tree).
You will see the 1 day / 7 day chart. Use the pull-down menu to select the desired view.
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I agree what you are seeing. The Daily graph pretty much matches my MRTG Graphing via SNMP, however, the weekly graph seems to be missing data. Sustained periods of traffic that cnMaestro isn't showing.
