DFM Polling and reporting

Unanswered Question

I have a question regarding DFM and how/what it polls when looking at utilization and up/down.

How does DFM calculate over utilization? what is it looking at? how accurate and timely is the information?

with up/down, is it simply the polling that will tell me that a device is down? A syslog message that tells me it is backup?


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David Stanford Tue, 04/15/2008 - 10:28
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Are you asking about interface utilization or CPU/Memory?

We poll different MIB objects to get this data, and as soon as you let me know what you want specifically I can let you know.

David Stanford Tue, 04/15/2008 - 10:48
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High Utilization

event definition:

CurrentUtilization > UtilizationThreshold;

CurrentUtilization =

((TrafficRate * 8) / MaxSpeed * 100;

TrafficRate =

= ifInOctetsRate + ifOutOctetsRate; if DuplexMode is HALFDUPLEX

= max(ifInOctetsRate, ifOutOctetsRate) if DuplexMode is FULLDUPLEX

ifInOctetsRate =

= rate(ifInOctets, PollingInterval);

ifOutOctetsRate =

= rate(ifOutOctets, PollingInterval);

UtilizationThreshold = 40




or High capacity counter (not supported by all OS versions)



To simulate high utilization, use the following value:

MaxSpeed/8 * 0.5

You can find MaxSpeed from Interface/Port property sheet.

The counters will wrap after sometime. Please make sure the rate

calculation is right when counters wrap.

expected: PerformanceException

-- HighUtilization

David Stanford Tue, 04/15/2008 - 10:49
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The time depends on our polling intervals configured in DFM (pollings and thresholds configuration)


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