In this post I’ll show you how to read SMART attributes using PowerShell and Smartmontools. I decided to use Powershell and Smartmontools because it will work from the command line which is great for Windows Server Core machines and it can be scheduled to run in the background. I also needed a way to receive notifications if the SMART attributes predicted disk failure. I decided to use Azure Log Analytics and Azure Monitor Alerts since I already use it for other tasks.
DISCLAIMER: I used this for my lab machines, it is not a practical or scalable solution for production.
Checking Drives For Failure Based On SMART Attributes
Windows already exposes the predicted failure status of drives based on SMART attributes so you don’t have to interpret the attributes yourself.
Get-WmiObject -namespace root\wmi –class MSStorageDriver_FailurePredictStatusBut if you want to you can retrieve more detailed SMART attribute data using PowerShell. There are various commands returning different levels of detail, for example:
Get-Disk | Get-StorageReliabilityCounter | fl
Get-WmiObject -namespace root\wmi –class MSStorageDriver_FailurePredictThresholds
Get-WmiObject -namespace root\wmi –class MSStorageDriver_FailurePredictDataIf you feel brave you can read the raw SMART attributes but you’ll have to manipulate them to get something in a human readable form.
Get-WmiObject -namespace root\wmi –class MSStorageDriver_ATAPISMartData | Select-Object -ExpandProperty VendorSpecificFor my purposes I retrieve the disks that have the PredictFailure property set to true.
$failures = Get-WmiObject -namespace root\wmi –class MSStorageDriver_FailurePredictStatus -ErrorAction SilentlyContinue | Select InstanceName, PredictFailure, Reason | Where-Object -Property PredictFailure -EQ $trueTo receive notifications for the predicted failures I write an error event to the Windows System Event Log.
Write-EventLog -LogName 'System' -Source 'YourSourceName' -EntryType Error -EventId 0 -Category 0 -Message "SMART Failure Prediction"Before you write to the Event Log you have to register as a source.
New-EventLog -LogName 'System' -Source 'YourSourceName' If you are not registered as an event source you will get “The description for Event ID 0 from source source cannot be found.” as part of your event message.
The full script can be found here.
The error event will be picked up by Azure Log Analytics if you are collecting the System Event Log error entries.
If you need more information on creating alerts read this post.
Retrieving SMART Attributes Using SmartMonTools
Apart from retrieving the failure status I also want to retrieve some extra SMART attributes from the disks. This data is for the next stage of my pet project to create some reports and track the degradation of the disks over time.
I’m using smartctl.exe from the Smartmontools package link. It works from the command line and it can return output in Json format. You can unzip the installer for Windows to get the bin folder containing the exe files.
In short I scan for drives and retrieve the SMART attributes for each one in JSON format and dump the attributes I need to a CSV file. The full script is to long to post but you can find it here.
Later on I will import this into a database for reporting. You could potentially leave it as JSON if you are going to use a document database but I’m leaning towards SQL at the moment.
