I’ve noticed that one of our Windows servers gives a critical alert when its disk idle time is greater than 100%, as below. This has me confused because it’s impossible to have an idle time of greater than 100%, and yet we seem to have managed it. I’ve done some research and I can’t see anything similar out there, but it’s a preconfigured Icinga alert, so it must have come from somewhere.
Could somebody please explain how this is possible, and why one would want to monitor for it please? It seems reasonable that you would want to look for anomalies, but this is a weird one. For what it’s worth, this server has quite a number of disks attached to it (~10).
Alert some of the alert output:
Overall Status - CRITICAL (Sample Period 58 sec) - [Triggered by _PercentIdleTime>100] - Logical Drive Name="C:" (CRITICAL - [Triggered by _PercentIdleTime>100]) - _PercentIdleTime=101%, _PercentBusyTime=-1%, _PercentDiskTime=2%, _PercentDiskReadTime=2%, _PercentDiskWriteTime=0%, _DiskReadBytesPersec=43.711KB/sec, _DiskReadsPersec=4/sec, _DiskWriteBytesPersec=24.225KB/sec, _DiskWritesPersec=3/sec