Desired State Configuration extension with Azure Resource Manager templates

This article describes the Azure Resource Manager template for the Desired State Configuration (DSC) extension handler.

Note

You might encounter slightly different schema examples. The change in schema occurred in the October 2016 release. For details, see Update from the previous format.

Template example for a Windows VM

The following snippet goes in the Resource section of the template. The DSC extension inherits default extension properties. For more information, see VirtualMachineExtension class.

{
    "type": "Microsoft.Compute/virtualMachines/extensions",
    "name": "[concat(parameters('VMName'),'/Microsoft.Powershell.DSC')]",
    "apiVersion": "2017-12-01",
    "location": "[resourceGroup().location]",
    "dependsOn": [
        "[concat('Microsoft.Compute/virtualMachines/', parameters('VMName'))]"
    ],
    "properties": {
        "publisher": "Microsoft.Powershell",
        "type": "DSC",
        "typeHandlerVersion": "2.76",
        "autoUpgradeMinorVersion": true,
        "settings": {
            "protectedSettings": {
                "Items": {
                    "registrationKeyPrivate": "registrationKey"
                }
            },
            "publicSettings": {
                "configurationArguments": [{
                        "Name": "RegistrationKey",
                        "Value": {
                            "UserName": "PLACEHOLDER_DONOTUSE",
                            "Password": "PrivateSettingsRef:registrationKeyPrivate"
                        }
                    },
                    {
                        "RegistrationUrl": "registrationUrl",
                    },
                    {
                        "NodeConfigurationName": "nodeConfigurationName"
                    }
                ]
            }
        }
    }
}

Template example for Windows virtual machine scale sets

A virtual machine scale set node has a properties section that has a VirtualMachineProfile, extensionProfile attribute. Under extensions, add the details for DSC Extension.

The DSC extension inherits default extension properties. For more information, see VirtualMachineScaleSetExtension class.

"extensionProfile": {
    "extensions": [{
        "type": "Microsoft.Compute/virtualMachines/extensions",
        "name": "[concat(parameters('VMName'),'/Microsoft.Powershell.DSC')]",
        "apiVersion": "2017-12-01",
        "location": "[resourceGroup().location]",
        "dependsOn": [
            "[concat('Microsoft.Compute/virtualMachines/', parameters('VMName'))]"
        ],
        "properties": {
            "publisher": "Microsoft.Powershell",
            "type": "DSC",
            "typeHandlerVersion": "2.76",
            "autoUpgradeMinorVersion": true,
            "settings": {
                "protectedSettings": {
                    "Items": {
                        "registrationKeyPrivate": "registrationKey"
                    }
                },
                "publicSettings": {
                    "configurationArguments": [{
                            "Name": "RegistrationKey",
                            "Value": {
                                "UserName": "PLACEHOLDER_DONOTUSE",
                                "Password": "PrivateSettingsRef:registrationKeyPrivate"
                            },
                        },
                        {
                            "RegistrationUrl": "registrationUrl",
                        },
                        {
                            "NodeConfigurationName": "nodeConfigurationName"
                        }
                    ]
                }
            },
        }
    }]
}

Detailed settings information

Use the following schema in the settings section of the Azure DSC extension in a Resource Manager template.

For a list of the arguments that are available for the default configuration script, see Default configuration script.

"settings": {
    "wmfVersion": "latest",
    "configuration": {
        "url": "http://validURLToConfigLocation",
        "script": "ConfigurationScript.ps1",
        "function": "ConfigurationFunction"
    },
    "configurationArguments": {
        "argument1": "Value1",
        "argument2": "Value2"
    },
    "configurationData": {
        "url": "https://foo.psd1"
    },
    "privacy": {
        "dataCollection": "enable"
    },
    "advancedOptions": {
        "downloadMappings": {
            "customWmfLocation": "http://myWMFlocation"
        }
    }
},
"protectedSettings": {
    "configurationArguments": {
        "parameterOfTypePSCredential1": {
            "userName": "UsernameValue1",
            "password": "PasswordValue1"
        },
        "parameterOfTypePSCredential2": {
            "userName": "UsernameValue2",
            "password": "PasswordValue2"
        }
    },
    "configurationUrlSasToken": "?g!bber1sht0k3n",
    "configurationDataUrlSasToken": "?dataAcC355T0k3N"
}

Details

Property name Type Description
settings.wmfVersion string Specifies the version of Windows Management Framework (WMF) that should be installed on your VM. Setting this property to latest installs the most recent version of WMF. Currently, the only possible values for this property are 4.0, 5.0, 5.0PP, and latest. These possible values are subject to updates. The default value is latest.
settings.configuration.url string Specifies the URL location from which to download your DSC configuration .zip file. If the URL provided requires an SAS token for access, set the protectedSettings.configurationUrlSasToken property to the value of your SAS token. This property is required if settings.configuration.script or settings.configuration.function are defined. If no value is given for these properties, the extension calls the default configuration script to set Location Configuration Manager (LCM) metadata, and arguments should be supplied.
settings.configuration.script string Specifies the file name of the script that contains the definition of your DSC configuration. This script must be in the root folder of the .zip file that's downloaded from the URL specified by the configuration.url property. This property is required if settings.configuration.url or settings.configuration.script are defined. If no value is given for these properties, the extension calls the default configuration script to set LCM metadata, and arguments should be supplied.
settings.configuration.function string Specifies the name of your DSC configuration. The configuration that is named must be included in the script that configuration.script defines. This property is required if settings.configuration.url or settings.configuration.function are defined. If no value is given for these properties, the extension calls the default configuration script to set LCM metadata, and arguments should be supplied.
settings.configurationArguments Collection Defines any parameters that you want to pass to your DSC configuration. This property is not encrypted.
settings.configurationData.url string Specifies the URL from which to download your configuration data (.psd1) file to use as input for your DSC configuration. If the URL provided requires an SAS token for access, set the protectedSettings.configurationDataUrlSasToken property to the value of your SAS token.
settings.privacy.dataEnabled string Enables or disables telemetry collection. The only possible values for this property are Enable, Disable, '', or $null. Leaving this property blank or null enables telemetry. The default value is ''. For more information, see Azure DSC extension data collection.
settings.advancedOptions.downloadMappings Collection Defines alternate locations from which to download WMF. For more information, see Azure DSC extension 2.8 and how to map downloads of the extension dependencies to your own location.
protectedSettings.configurationArguments Collection Defines any parameters that you want to pass to your DSC configuration. This property is encrypted.
protectedSettings.configurationUrlSasToken string Specifies the SAS token to use to access the URL that configuration.url defines. This property is encrypted.
protectedSettings.configurationDataUrlSasToken string Specifies the SAS token to use to access the URL that configurationData.url defines. This property is encrypted.

Default configuration script

For more information about the following values, see Local Configuration Manager basic settings. You can use the DSC extension default configuration script to configure only the LCM properties that are listed in the following table.

Property name Type Description
settings.configurationArguments.RegistrationKey securestring Required property. Specifies the key that's used for a node to register with the Azure Automation service as the password of a PowerShell credential object. This value can be automatically discovered by using the listkeys method against the Automation account. The value should be secured as a protected setting.
settings.configurationArguments.RegistrationUrl string Required property. Specifies the URL of the Automation endpoint where the node attempts to register. This value can be automatically discovered by using the reference method against the Automation account.
settings.configurationArguments.NodeConfigurationName string Required property. Specifies the node configuration in the Automation account to assign to the node.
settings.configurationArguments.ConfigurationMode string Specifies the mode for LCM. Valid options include ApplyOnly, ApplyandMonitor, and ApplyandAutoCorrect. The default value is ApplyandMonitor.
settings.configurationArguments.RefreshFrequencyMins uint32 Specifies how often LCM attempts to check with the Automation account for updates. Default value is 30. Minimum value is 15.
settings.configurationArguments.ConfigurationModeFrequencyMins uint32 Specifies how often LCM validates the current configuration. Default value is 15. Minimum value is 15.
settings.configurationArguments.RebootNodeIfNeeded boolean Specifies whether a node can be automatically rebooted if a DSC operation requests it. Default value is false.
settings.configurationArguments.ActionAfterReboot string Specifies what happens after a reboot when applying a configuration. Valid options are ContinueConfiguration and StopConfiguration. Default value is ContinueConfiguration.
settings.configurationArguments.AllowModuleOverwrite boolean Specifies whether LCM overwrites existing modules on the node. Default value is false.

Settings vs. ProtectedSettings

All settings are saved in a settings text file on the VM. Properties listed under settings are public properties. Public properties aren't encrypted in the settings text file. Properties listed under protectedSettings are encrypted with a certificate and are not shown in plain text in the settings file on the VM.

If the configuration needs credentials, you can include the credentials in protectedSettings:

"protectedSettings": {
    "configurationArguments": {
        "parameterOfTypePSCredential1": {
            "userName": "UsernameValue1",
            "password": "PasswordValue1"
        }
    }
}

Example configuration script

The following example shows the default behavior for the DSC extension, which is to provide metadata settings to LCM and register with the Automation DSC service. Configuration arguments are required. Configuration arguments are passed to the default configuration script to set LCM metadata.

"settings": {
    "configurationArguments": {
        {
            "Name": "RegistrationKey",
            "Value": {
                "UserName": "PLACEHOLDER_DONOTUSE",
                "Password": "PrivateSettingsRef:registrationKeyPrivate"
            },
        },
        "RegistrationUrl": "[parameters('registrationUrl1')]",
        "NodeConfigurationName": "nodeConfigurationNameValue1"
    }
},
"protectedSettings": {
    "Items": {
        "registrationKeyPrivate": "[parameters('registrationKey1']"
    }
}

Example using the configuration script in Azure Storage

The following example is from the DSC extension handler overview. This example uses Resource Manager templates instead of cmdlets to deploy the extension. Save the IisInstall.ps1 configuration, place it in a .zip file, and then upload the file in an accessible URL. This example uses Azure Blob storage, but you can download .zip files from any arbitrary location.

In the Resource Manager template, the following code instructs the VM to download the correct file, and then run the appropriate PowerShell function:

"settings": {
    "configuration": {
        "url": "https://demo.blob.core.windows.net/",
        "script": "IisInstall.ps1",
        "function": "IISInstall"
    }
},
"protectedSettings": {
    "configurationUrlSasToken": "odLPL/U1p9lvcnp..."
}

Update from a previous format

Any settings in a previous format of the extension (and which have the public properties ModulesUrl, ConfigurationFunction, SasToken, or Properties) automatically adapt to the current format of the extension. They run just as they did before.

The following schema shows what the previous settings schema looked like:

"settings": {
    "WMFVersion": "latest",
    "ModulesUrl": "https://UrlToZipContainingConfigurationScript.ps1.zip",
    "SasToken": "SAS Token if ModulesUrl points to private Azure Blob Storage",
    "ConfigurationFunction": "ConfigurationScript.ps1\\ConfigurationFunction",
    "Properties": {
        "ParameterToConfigurationFunction1": "Value1",
        "ParameterToConfigurationFunction2": "Value2",
        "ParameterOfTypePSCredential1": {
            "UserName": "UsernameValue1",
            "Password": "PrivateSettingsRef:Key1"
        },
        "ParameterOfTypePSCredential2": {
            "UserName": "UsernameValue2",
            "Password": "PrivateSettingsRef:Key2"
        }
    }
},
"protectedSettings": {
    "Items": {
        "Key1": "PasswordValue1",
        "Key2": "PasswordValue2"
    },
    "DataBlobUri": "https://UrlToConfigurationDataWithOptionalSasToken.psd1"
}

Here's how the previous format adapts to the current format:

Property name Previous schema equivalent
settings.wmfVersion settings.WMFVersion
settings.configuration.url settings.ModulesUrl
settings.configuration.script First part of settings.ConfigurationFunction (before \\)
settings.configuration.function Second part of settings.ConfigurationFunction (after \\)
settings.configurationArguments settings.Properties
settings.configurationData.url protectedSettings.DataBlobUri (without SAS token)
settings.privacy.dataEnabled settings.Privacy.DataEnabled
settings.advancedOptions.downloadMappings settings.AdvancedOptions.DownloadMappings
protectedSettings.configurationArguments protectedSettings.Properties
protectedSettings.configurationUrlSasToken settings.SasToken
protectedSettings.configurationDataUrlSasToken SAS token from protectedSettings.DataBlobUri

Troubleshooting - Error code 1100

Error Code 1100 indicates a problem with the user input to the DSC extension. The text of these errors varies, and might change. Here are some of the errors you might run into, and how you can fix them.

Invalid values

"Privacy.dataCollection is '{0}'. The only possible values are '', 'Enable', and 'Disable'". "WmfVersion is '{0}'. Only possible values are … and 'latest'".

Problem: A provided value is not allowed.

Solution: Change the invalid value to a valid value. For more information, see the table in Details.

Invalid URL

"ConfigurationData.url is '{0}'. This is not a valid URL" "DataBlobUri is '{0}'. This is not a valid URL" "Configuration.url is '{0}'. This is not a valid URL"

Problem: A provided URL is not valid.

Solution: Check all your provided URLs. Ensure that all URLs resolve to valid locations that the extension can access on the remote machine.

Invalid ConfigurationArgument type

"Invalid configurationArguments type {0}"

Problem: The ConfigurationArguments property can't resolve to a Hashtable object.

Solution: Make your ConfigurationArguments property a Hashtable. Follow the format provided in the preceding example. Watch for quotes, commas, and braces.

Duplicate ConfigurationArguments

"Found duplicate arguments '{0}' in both public and protected configurationArguments"

Problem: The ConfigurationArguments in public settings and the ConfigurationArguments in protected settings have properties with the same name.

Solution: Remove one of the duplicate properties.

Missing properties

"Configuration.function requires that configuration.url or configuration.module is specified"

"Configuration.url requires that configuration.script is specified"

"Configuration.script requires that configuration.url is specified"

"Configuration.url requires that configuration.function is specified"

"ConfigurationUrlSasToken requires that configuration.url is specified"

"ConfigurationDataUrlSasToken requires that configurationData.url is specified"

Problem: A defined property needs another property, which is missing.

Solutions:

  • Provide the missing property.
  • Remove the property that needs the missing property.

Next steps