NetXMS Forum

I have added additional info to my original post as FYI.

Hello,
I'm experiencing this error after implementing MTBF (Mean Time Between Failures) and MTTR (Mean Time To Repair) Calculation

This is related to the "Node availability (percentage)" DCI only (other DCIs are OK):
See attached Capture1.PNG

Here's the error msg:
See attached Capture3.PNG

Here's the line of code being referred to:
See attached Capture2.PNG

Here's the full script:

// This script calculates MTTR, MTBF and perAvailability parameters and stores them in custom attributes
// Initialize some custom attributes the first time.
// Undefined attributes are created by SetCustomAttribute function automatically
CurrentStatus = GetDCIValue($node, FindDCIByName($node, "Status"));
PreviousState = GetCustomAttribute($node, "PreviousState");
if (PreviousState == null)
{ // In the first time, previous state is null
	SetCustomAttribute($node, "PreviousState", CurrentStatus);
	SetCustomAttribute($node, "TimeStamp", time());
	SetCustomAttribute($node, "NumFailures", 0);
	SetCustomAttribute($node, "TotalUptime", 0);
	SetCustomAttribute($node, "TotalDowntime", 0);
	return 100;
}

// From here the 2nd and subsequent times
NumFailures = GetCustomAttribute($node, "NumFailures");
LastTime = time() - GetCustomAttribute($node, "TimeStamp");

// Status is up
if (CurrentStatus == 0)
{
	if (PreviousState != CurrentStatus)
	{   // just changed to up
		// update mttr
		TotalDowntime = GetCustomAttribute($node, "TotalDowntime") + LastTime;
		mttr = TotalDowntime / ((NumFailures == 0) ? 1 : NumFailures) / 3600;   // to prevent division by ze
		SetCustomAttribute($node, "TotalDowntime", TotalDowntime);
		SetCustomAttribute($node, "mttr", mttr);
	}
	else
	{      // still up
		// update mtbf
		TotalUptime = GetCustomAttribute($node, "TotalUptime") + LastTime;
		mtbf = TotalUptime / ((NumFailures == 0) ? 1 : NumFailures) / 3600;   // to prevent division by zero
		SetCustomAttribute($node, "TotalUptime", TotalUptime);
		SetCustomAttribute($node, "mtbf", mtbf);
	}
}

// Status is down
if (CurrentStatus == 4)
{
	if (PreviousState != CurrentStatus)
	{   // just changed to down
		// update mtbf
		NumFailures++;
		TotalUptime = GetCustomAttribute($node, "TotalUptime") + LastTime;
		mtbf = TotalUptime / NumFailures / 3600;
		SetCustomAttribute($node, "NumFailures", NumFailures);
		SetCustomAttribute($node, "TotalUptime", TotalUptime);
		SetCustomAttribute($node, "mtbf", mtbf);
	}
	else
	{   // still down
		// update mttr
		TotalDowntime = GetCustomAttribute($node, "TotalDowntime") + LastTime;
		mttr = TotalDowntime / NumFailures / 3600;
		SetCustomAttribute($node, "TotalDowntime", TotalDowntime);
		SetCustomAttribute($node, "mttr", mttr);
	}
}

if (CurrentStatus == 0 || CurrentStatus == 4)
{
	// Save previous state and timestamp
	SetCustomAttribute($node, "PreviousState", CurrentStatus);
	SetCustomAttribute($node, "TimeStamp", time());

	// perAvailability section
	TotalUptime = GetCustomAttribute($node, "TotalUptime");
	TotalDowntime = GetCustomAttribute($node, "TotalDowntime");
	perAvailability = TotalUptime / (TotalUptime + TotalDowntime) * 100;
	SetCustomAttribute($node, "perAvailability", perAvailability);

	return perAvailability;
}

Appreciate any help.
Thanks

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