Windows Server · Risk: High · Documentation Verified
Last verified: 2026-10-26
Microsoft Storage reference: Starts Storage diagnostic logging. The syntax and selected example below are adapted from the pinned Windows Server 2025 reference. Module availability, target configuration and delegated permissions determine whether it can run in your environment. Documentation and parameter text: Microsoft, CC BY 4.0; formatting adapted by Cmdlet World. No execution testing is claimed.
Use an account with the target resource permissions documented for Start-StorageDiagnosticLog. Modifying administrative cmdlets may require elevation or delegated administration. This catalog does not assert that ordinary users can execute the command.
Supported environments
Windows / Storage · Windows Server 2025 documentation; feature/module prerequisites apply
Parameters
-AsJob
Runs the cmdlet as a background job. Use this parameter to run commands that take a long time to complete.
-CimSession
Runs the cmdlet in a remote session or on a remote computer. Enter a computer name or a session object, such as the output of a New-CimSession or Get-CimSession cmdlet. The default is the current session on the local computer.
-InputObject (required)
Specifies the input object that is used in a pipeline command.
-Level
Specifies the maximum level of tracing to gather. The acceptable values for this parameter are: - Critical - Error - Warning - Informational - Verbose The default value is Informational.
-MaxLogSize
Specifies the log size, in bytes. The default size of 200 MB. The log is circular, so when the log is full, older entries are overwritten. You can use this parameter when you want to record more data or when you want to set a smaller log size to save disk space.
-PassThru
Returns an object representing the item with which you are working. By default, this cmdlet does not generate any output.
-StorageSubSystemFriendlyName (required)
Specifies the friendly name of the Storage subsystem for which to gather storage diagnostics. It may denote the Storage subsystem of the local computer (on which the cmdlet is run) or a remote Storage subsystem (standalone or cluster). Selecting the local subsystem: - On a standalone machine, no remote subsystems: All logs are gathered for that computer. - On a standalone machine, remote subsystems registered: All logs are gathered for the standalone machine, including the client-side remoting calls. - On a cluster node: All logs for that particular cluster node are gathered, even ones that belong in the cluster subsystem for that node only. None of the other nodes are logged. Selecting the cluster subsystem: - All logs are gathered for each node in that cluster. This includes and logs or tracing that may correspond to a node's local subsystem. Selecting a remote subsystem: - Tracing and logs are only gathered for the remote endpoint. What logs and tracing are gathered depend on whether it is a cluster or a standalone machine (see above cases). - Tracing and logs for the client-side operations (running on the management node) are not collected. It is expected that if there is a failure, it is most likely in the remote subsystem. In order to gather the client-side calls, you must also include the management node's local subsystem.
-StorageSubSystemName (required)
Specifies the name of the Storage subsystem for which to gather Storage diagnostics. It may denote the Storage subsystem of the local computer (on which the cmdlet is run) or a remote Storage subsystem (standalone or cluster). Selecting the local subsystem: - On a standalone machine, no remote subsystems: All logs are gathered for that computer. - On a standalone machine, remote subsystems registered: All logs are gathered for the standalone machine, including the client-side remoting calls. - On a cluster node: All logs for that particular cluster node are gathered, even ones that belong in the cluster subsystem for that node only. None of the other nodes are logged. Selecting the cluster subsystem: - All logs are gathered for each node in that cluster. This includes and logs or tracing that may correspond to a node's local subsystem. Selecting a remote subsystem: - Tracing and logs are only gathered for the remote endpoint. What logs and tracing are gathered depend on whether it is a cluster or a standalone machine (see above cases). - Tracing and logs for the client-side operations (running on the management node) are not collected. It is expected that if there is a failure, it is most likely in the remote subsystem. In order to gather the client-side calls, you must also include the management node's local subsystem.
-StorageSubSystemUniqueId (required)
Specifies the unique ID of the Storage subsystem for which to gather Storage diagnostics. It may denote the Storage subsystem of the local computer (on which the cmdlet is run) or a remote Storage subsystem (standalone or cluster). Selecting the local subsystem: - On a standalone machine, no remote subsystems: All logs are gathered for that computer. - On a standalone machine, remote subsystems registered: All logs are gathered for the standalone machine, including the client-side remoting calls. - On a cluster node: All logs for that particular cluster node are gathered, even ones that belong in the cluster subsystem for that node only. None of the other nodes are logged. Selecting the cluster subsystem: - All logs are gathered for each node in that cluster. This includes and logs or tracing that may correspond to a node's local subsystem. Selecting a remote subsystem: - Tracing and logs are only gathered for the remote endpoint. What logs and tracing are gathered depend on whether it is a cluster or a standalone machine (see above cases). - Tracing and logs for the client-side operations (running on the management node) are not collected. It is expected that if there is a failure, it is most likely in the remote subsystem. In order to gather the client-side calls, you must also include the management node's local subsystem.
-ThrottleLimit
Specifies the maximum number of concurrent operations that can be established to run the cmdlet. If this parameter is omitted or a value of 0 is entered, then Windows PowerShell® calculates an optimum throttle limit for the cmdlet based on the number of CIM cmdlets that are running on the computer. The throttle limit applies only to the current cmdlet, not to the session or to the computer.
Prerequisites
Windows with the Storage module and the Windows feature or management tools that provide it. Confirm target connectivity and version compatibility using the linked Microsoft reference.
Security considerations
This cmdlet changes system state. Review every target and parameter in the official reference, test outside production, and prepare an appropriate backup or rollback. Do not execute the example automatically.
The first command starts the on-demand Storage diagnostic log session on a cluster subsystem. The second command stops the diagnostic logs session. The third command gets the diagnostic files and places them in C:\logs\techsupport. Source: Microsoft, CC BY 4.0; transcript prompt/output removed. This example was not executed.