Failed to create session host in host pool, deployment failed but created VM still running

Question

when create hostpool session hosts, deployment failed with report error

{

"code": "DeploymentFailed",

"target": "[REDACTED]",

"message": "At least one resource deployment operation failed. Please list deployment operations for details. Please see https://aka.ms/arm-deployment-operations for usage details.",

"details": [

{

  "code": "ResourceDeploymentFailure",

  "

  "message": "The resource write operation failed to complete successfully, because it reached terminal provisioning state 'Failed'."

}
  ]

}

Operation details:

{

json
"status": "Failed",

"error": {

    "code": "DeploymentFailed",

    "message": "At least one resource deployment operation failed. Please list deployment operations for details. Please see https://aka.ms/arm-deployment-operations for usage details.",

    "details": [

        {

            "code": "Conflict",

            "message": "{\r\n  \"status\": \"Failed\",\r\n  \"error\": {\r\n    \"code\": \"ResourceDeploymentFailure\",\r\n    \"message\": \"The resource write operation failed to complete successfully, because it reached terminal provisioning state 'Failed'.\",\r\n    \"details\": [\r\n      {\r\n        \"code\": \"VMExtensionProvisioningError\",\r\n        \"message\": \"VM has reported a failure when processing extension 'Microsoft.PowerShell.DSC' (publisher 'Microsoft.Powershell' and type 'DSC'). Error message: 'The DSC Extension failed to execute: Error downloading https://wvdportalstorageblob.blob.core.windows.net/galleryartifacts/Configuration_1.0.03313.1159.zip after 17 attempts: Unable to connect to the remote server.\\r\\nMore information about the failure can be found in the logs located under 'C:\\\\WindowsAzure\\\\Logs\\\\Plugins\\\\Microsoft.Powershell.DSC\\\\2.83.5' on the VM.'. More information on troubleshooting is available at https://aka.ms/VMExtensionDSCWindowsTroubleshoot\"\r\n      }\r\n    ]\r\n  }\r\n}"

        }

    ]

}
}

Answer 1

Hello @Richard Liu

Thank you for sharing the detailed exception for the failure. Based on the error message, the failure occurred during the provisioning of the VM extension "Microsoft.PowerShell.DSC."

The specific error states:

The DSC Extension failed to execute: Error downloading https://wvdportalstorageblob.blob.core.windows.net/galleryartifacts/Configuration_1.0.03313.1159.zip after 17 attempts: Unable to connect to the remote server.

This indicates that the VM was unable to reach the required endpoint while attempting to download the extension package. As a result, the extension provisioning failed, which led to the overall VM deployment failure.

Please review the following:

1. Check Network Connectivity Verify your network configuration and firewall settings to ensure that required endpoints such as *.wvd.microsoft.com and *.servicebus.windows.net are reachable from your environment.
2. Validate Required URLs Confirm that all mandatory URLs for Azure Virtual Desktop are accessible from the session host. Review the list of required endpoints to ensure there are no network blocks or restrictions in place.

Additionally, you can use the Azure Virtual Desktop Agent URL Tool on an existing session host (ensure it is on the same network where you are attempting to deploy the new session host). Please follow the guidance provided here: https://learn.microsoft.com/en-us/azure/virtual-desktop/check-access-validate-required-fqdn-endpoint#use-the-azure-virtual-desktop-agent-url-tool

1. Firewall and Proxy Settings If firewalls or proxy servers are in use, ensure they are not blocking outbound connectivity to the required Azure services.