PRTG Manual: WMI Logical Disk I/O Sensor

The WMI Logical Disk I/O sensor monitors the disk usage of a logical disk or mount point on a Windows system via Windows Management Instrumentation (WMI).

The sensor shows performance data of counters that monitor logical partitions of a hard drive. The system monitor identifies logical disk instances by their identifier, such as C, and the sensor reads the logical disk object in the system monitor and returns the values.

For a detailed list and descriptions of the channels that this sensor can show, see section Channel List.

Sensor in Other Languages

Dutch: WMI Logische Schijf I/O
French: Disque logique E/S (WMI)
German: WMI Logischer Datenträger E/A
Japanese: WMI 論理ディスク I/O
Portuguese: E/S do disco lógico (WMI)
Russian: Ввод-вывод логического диска WMI
Simplified Chinese: WMI 逻辑磁盘 I/O
Spanish: E/S de disco lógico (WMI)

Remarks

Consider the following remarks and requirements for this sensor:

Remark	Description
Performance impact	This sensor has a high performance impact. Stay below 200 WMI sensors per probe. Above this number, consider using multiple remote probes for load balancing.
WoW64	This sensor requires WoW64 (Windows 32-bit on Windows 64-bit) for target systems that run Windows Server 2016.
Windows version	This sensor requires at least Windows Server 2008 R2. It does not work on previous Windows versions (Windows Server 2008 or earlier).
Credentials	This sensor requires credentials for Windows systems.
IPv6	This sensor supports IPv6.
Hosted probe	You cannot add this sensor to the hosted probe of a PRTG Hosted Monitor instance. If you want to use this sensor, add it to a remote probe device.

Basic Sensor Settings

The sensor has the following default tags that are automatically predefined in the sensor's settings when you add the sensor:

wmilogicalsensor

For more information about basic sensor settings, see section Sensor Settings.

WMI Logical Disk I/O Specific

Setting	Description
Disk	The logical disk or mount point that this sensor monitors.

Debug Options

Setting	Description
Result Handling	Define what PRTG does with the sensor result: Discard result (default): Do not store the sensor result. Store result: Store the sensor result and the last response in the \Logs\sensors subfolder of the PRTG data directory on the probe system. The file names are Result of Sensor [ID].txt and Result of Sensor [ID].Data.txt. This setting is for debugging purposes. PRTG overwrites these files with each scanning interval. In a cluster, PRTG stores the result in the PRTG data directory of the master node.

Setting

Description

Result Handling

Define what PRTG does with the sensor result:

Discard result (default): Do not store the sensor result.
Store result: Store the sensor result and the last response in the \Logs\sensors subfolder of the PRTG data directory on the probe system. The file names are Result of Sensor [ID].txt and Result of Sensor [ID].Data.txt. This setting is for debugging purposes. PRTG overwrites these files with each scanning interval.

In a cluster, PRTG stores the result in the PRTG data directory of the master node.

Sensor Display

Setting	Description
Primary Channel	Select a channel from the list to define it as the primary channel. In the device tree, PRTG displays the last value of the primary channel below the sensor's name. The available options depend on what channels are available for this sensor. You can set a different primary channel later by clicking below a channel gauge on the sensor's Overview tab.
Graph Type	Define how this sensor shows different channels: Show channels independently (default): Show a graph for each channel. Stack channels on top of each other: Stack channels on top of each other to create a multi-channel graph. This generates a graph that visualizes the different components of your total traffic. You cannot use this option in combination with manual Vertical Axis Scaling (available in the channel settings).
Stack Unit	This setting is only visible if you select Stack channels on top of each other above. Select a unit from the list. PRTG stacks all channels with this unit on top of each other. By default, you cannot exclude single channels from stacking if they use the selected unit. However, there is an advanced procedure to do so.

Setting

Description

Primary Channel

Select a channel from the list to define it as the primary channel. In the device tree, PRTG displays the last value of the primary channel below the sensor's name. The available options depend on what channels are available for this sensor.

You can set a different primary channel later by clicking below a channel gauge on the sensor's Overview tab.

Graph Type

Define how this sensor shows different channels:

Show channels independently (default): Show a graph for each channel.
Stack channels on top of each other: Stack channels on top of each other to create a multi-channel graph. This generates a graph that visualizes the different components of your total traffic.
You cannot use this option in combination with manual Vertical Axis Scaling (available in the channel settings).

Stack Unit

This setting is only visible if you select Stack channels on top of each other above.

Select a unit from the list. PRTG stacks all channels with this unit on top of each other. By default, you cannot exclude single channels from stacking if they use the selected unit. However, there is an advanced procedure to do so.

Inherited Settings

By default, all of these settings are inherited from objects that are higher in the hierarchy. We recommend that you change them centrally in the root group settings if necessary. To change a setting for this object only, click under the corresponding setting name to disable the inheritance and to display its options.

For more information, see section Inheritance of Settings.

Channel List

Which channels the sensor actually shows might depend on the target device, the available components, and the sensor setup.

Channel	Description
Avg. Bytes Per Read	The average number of bytes per read
Avg. Bytes Per Transfer	The average number of bytes per transfer
Avg. Bytes Per Write	The average number of bytes per write
Avg. Queue Length	The average number of items in the queue
Avg. Read Queue	The average number of items in the read queue
Avg. Read Time	The average read time
Avg. Transfer Time	The average transfer time
Avg. Write Queue	The average number of items in the write queue
Avg. Write Time	The average write time
Current Queue	The current number of items in the queue
Disk IOs	The number of disk I/O operations
Disk Read	The disk read speed
Disk Read IOs	The number of disk read I/O operations
Disk Read Time %	The disk read time (%)
Disk Time %	The disk time (%)
Disk Transfer	The disk transfer speed
Disk Write	The disk write speed
Disk Write IOs	The number of disk write I/O operations
Disk Write Time %	The disk write time (%)
Downtime	In the channel table on the Overview tab, this channel never shows any values. PRTG uses this channel in graphs and reports to show the amount of time in which the sensor was in the Down status.
Free Space	The free space
Free Space %	The free space (%) This channel is the primary channel by default.
Idle Time %	The idle time (%)
Split IOs	The number of split I/O operations