Azure VM Scale Set CustomScriptExtension Failing - azure

Question

I'm trying to create a windows Azure VM Scale Set that auto provisions a formatted attached data disk using the MS guide here: https://learn.microsoft.com/en-us/azure/virtual-machine-scale-sets/virtual-machine-scale-sets-attached-disks
No matter what I do I see to get this error:
9:14:16 PM - The deployment 'testvmss' failed with error(s). Showing
1 out of 1 error(s). Status
| Message: VM has reported a failure when processing extension 'customScript'. Error message: "Invalid
| Configuration - CommandToExecute is not specified in the configuration; it must be specified in either
| the protected or public configuration section" More information on troubleshooting is available at
| https://aka.ms/VMExtensionCSEWindowsTroubleshoot (Code:VMExtensionProvisioningError) CorrelationId:
| 3294f49a-23f0-4634-aba0-3bb0e814659e
I've tried:
moving the "commandToExecute" into the protected config area
"typeHandlerVersion" numbers
moving commandToExecute outside of the "settings" section
using case corrected "CommandToExecute"
Simplifying the powershell statement to "powershell echo test"
Searching google for the error message, better/different examples, etc.
Here is the specific section of the ARM:
"extensionProfile": {
"extensions": [
{
"name": "customScript",
"properties": {
"publisher": "Microsoft.Compute",
"type": "CustomScriptExtension",
"typeHandlerVersion": "1.8",
"autoUpgradeMinorVersion": true,
"settings": {
"fileUris": ["https://raw.githubusercontent.com/Azure-Samples/compute-automation-configurations/master/prepare_vm_disks.ps1"],
"commandToExecute": "powershell.exe -ExecutionPolicy Unrestricted -File prepare_vm_disks.ps1"
}
}
}
]
}
And for reference, here is the full ARM:
{
"$schema": "http://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"location": {
"type": "string"
},
"virtualMachineScaleSetName": {
"type": "string"
},
"virtualMachineScaleSetRG": {
"type": "string"
},
"singlePlacementGroup": {
"type": "string"
},
"instanceSize": {
"type": "string"
},
"instanceCount": {
"type": "string"
},
"upgradeMode": {
"type": "string"
},
"priority": {
"type": "string"
},
"enableAcceleratedNetworking": {
"type": "string"
},
"subnetId": {
"type": "string"
},
"osDiskType": {
"type": "string"
},
"dataDisks": {
"type": "array"
},
"addressPrefixes": {
"type": "array"
},
"subnets": {
"type": "array"
},
"virtualNetworkId": {
"type": "string"
},
"virtualNetworkName": {
"type": "string"
},
"networkSecurityGroups": {
"type": "array"
},
"networkInterfaceConfigurations": {
"type": "array"
},
"vmName": {
"type": "string"
},
"scaleInPolicy": {
"type": "object"
},
"overprovision": {
"type": "bool"
},
"upgradePolicy": {
"type": "string"
},
"adminUsername": {
"type": "string"
},
"adminPassword": {
"type": "secureString"
},
"platformFaultDomainCount": {
"type": "string"
}
},
"variables": {
"storageApiVersion": "2019-04-01",
"namingInfix": "[toLower(substring(concat(parameters('virtualMachineScaleSetName'), uniqueString(resourceGroup().id)), 0, 9))]"
},
"resources": [
{
"name": "[parameters('virtualNetworkName')]",
"type": "Microsoft.Network/virtualNetworks",
"apiVersion": "2019-09-01",
"location": "[parameters('location')]",
"properties": {
"addressSpace": {
"addressPrefixes": "[parameters('addressPrefixes')]"
},
"subnets": "[parameters('subnets')]"
}
},
{
"name": "[parameters('networkSecurityGroups')[copyIndex()].name]",
"type": "Microsoft.Network/networkSecurityGroups",
"apiVersion": "2019-02-01",
"location": "[parameters('location')]",
"properties": {
"securityRules": "[parameters('networkSecurityGroups')[copyIndex()].rules]"
},
"copy": {
"name": "networkSecurityGroups",
"count": "[length(parameters('networkSecurityGroups'))]"
}
},
{
"name": "[parameters('virtualMachineScaleSetName')]",
"type": "Microsoft.Compute/virtualMachineScaleSets",
"apiVersion": "2019-12-01",
"location": "[parameters('location')]",
"dependsOn": [
"[concat('Microsoft.Network/virtualNetworks/', parameters('virtualNetworkName'))]",
"networkSecurityGroups",
"[concat('Microsoft.Network/virtualNetworks/', parameters('virtualNetworkName'))]"
],
"sku": {
"name": "[parameters('instanceSize')]",
"capacity": "[int(parameters('instanceCount'))]"
},
"properties": {
"overprovision": "[parameters('overprovision')]",
"upgradePolicy": {
"mode": "[parameters('upgradePolicy')]"
},
"singlePlacementGroup": "[parameters('singlePlacementGroup')]",
"virtualMachineProfile": {
"storageProfile": {
"osDisk": {
"createOption": "fromImage",
"caching": "ReadWrite",
"managedDisk": {
"storageAccountType": "[parameters('osDiskType')]"
}
},
"imageReference": {
"publisher": "MicrosoftWindowsServer",
"offer": "WindowsServer",
"sku": "2016-Datacenter",
"version": "latest"
},
"copy": [
{
"name": "dataDisks",
"count": "[length(parameters('dataDisks'))]",
"input": {
"lun": "[parameters('dataDisks')[copyIndex('dataDisks')].lun]",
"createOption": "[parameters('dataDisks')[copyIndex('dataDisks')].createOption]",
"caching": "[parameters('dataDisks')[copyIndex('dataDisks')].caching]",
"writeAcceleratorEnabled": "[parameters('dataDisks')[copyIndex('dataDisks')].writeAcceleratorEnabled]",
"diskSizeGB": "[parameters('dataDisks')[copyIndex('dataDisks')].diskSizeGB]",
"managedDisk": {
"storageAccountType": "[parameters('dataDisks')[copyIndex('dataDisks')].storageAccountType]",
"diskEncryptionSet": "[parameters('dataDisks')[copyIndex('dataDisks')].diskEncryptionSet]"
},
"diskIOPSReadWrite": "[if(equals( parameters('dataDisks')[copyIndex('dataDisks')].diskIOPSReadWrite, -1), json('null'),parameters('dataDisks')[copyIndex('dataDisks')].diskIOPSReadWrite)]",
"diskMBpsReadWrite": "[if(equals( parameters('dataDisks')[copyIndex('dataDisks')].diskMBpsReadWrite, -1), json('null'),parameters('dataDisks')[copyIndex('dataDisks')].diskMBpsReadWrite)]"
}
}
]
},
"priority": "[parameters('priority')]",
"networkProfile": {
"copy": [
{
"name": "networkInterfaceConfigurations",
"count": "[length(parameters('networkInterfaceConfigurations'))]",
"input": {
"name": "[parameters('networkInterfaceConfigurations')[copyIndex('networkInterfaceConfigurations')].name]",
"properties": {
"primary": "[parameters('networkInterfaceConfigurations')[copyIndex('networkInterfaceConfigurations')].primary]",
"enableAcceleratedNetworking": "[parameters('networkInterfaceConfigurations')[copyIndex('networkInterfaceConfigurations')].enableAcceleratedNetworking]",
"ipConfigurations": [
{
"name": "[concat(parameters('networkInterfaceConfigurations')[copyIndex('networkInterfaceConfigurations')].name, '-defaultIpConfiguration')]",
"properties": {
"subnet": {
"id": "[parameters('networkInterfaceConfigurations')[copyIndex('networkInterfaceConfigurations')].subnetId]"
},
"primary": "[parameters('networkInterfaceConfigurations')[copyIndex('networkInterfaceConfigurations')].primary]",
"applicationGatewayBackendAddressPools": "[parameters('networkInterfaceConfigurations')[copyIndex('networkInterfaceConfigurations')].applicationGatewayBackendAddressPools]",
"loadBalancerBackendAddressPools": "[parameters('networkInterfaceConfigurations')[copyIndex('networkInterfaceConfigurations')].loadBalancerBackendAddressPools]",
"loadBalancerInboundNatPools": "[parameters('networkInterfaceConfigurations')[copyIndex('networkInterfaceConfigurations')].loadBalancerInboundNatPools]",
"publicIPAddressConfiguration": "[if( equals( parameters('networkInterfaceConfigurations')[copyIndex('networkInterfaceConfigurations')].pipName, ''), json('null'), union(json(concat('{\"name\": \"', parameters('networkInterfaceConfigurations')[copyIndex('networkInterfaceConfigurations')].pipName, '\"}'))\n ,json('{\"properties\": { \"idleTimeoutInMinutes\": 15}}')))]"
}
}
],
"networkSecurityGroup": "[if( equals( parameters('networkInterfaceConfigurations')[copyIndex('networkInterfaceConfigurations')].nsgId, ''), json('null'),json(concat('{\"id\": \"', parameters('networkInterfaceConfigurations')[copyIndex('networkInterfaceConfigurations')].nsgId, '\"}')))]"
}
}
}
]
},
"extensionProfile": {
"extensions": [
{
"name": "customScript",
"properties": {
"publisher": "Microsoft.Compute",
"type": "CustomScriptExtension",
"typeHandlerVersion": "1.8",
"autoUpgradeMinorVersion": true,
"settings": {
"fileUris": ["https://raw.githubusercontent.com/Azure-Samples/compute-automation-configurations/master/prepare_vm_disks.ps1"],
"commandToExecute": "powershell.exe -ExecutionPolicy Unrestricted -File prepare_vm_disks.ps1"
}
}
}
]
},
"osProfile": {
"computerNamePrefix": "[variables('namingInfix')]",
"adminUsername": "[parameters('adminUsername')]",
"adminPassword": "[parameters('adminPassword')]",
"windowsConfiguration": {
"provisionVmAgent": true
}
}
},
"scaleInPolicy": "[parameters('scaleInPolicy')]",
"platformFaultDomainCount": "[parameters('platformFaultDomainCount')]"
}
}
],
"outputs": {
"adminUsername": {
"type": "string",
"value": "[parameters('adminUsername')]"
}
}
}
Any help is greatly appreciated, thanks!

Answer 1

I had the same issue with VMSS Managed Disk and Service Fabric, because there is a problem with the last commit (from last September) - Here you can find an open issue about it.
Until this issue would be solved you can still use the script extension with link to previous version as I did:
https://raw.githubusercontent.com/Azure-Samples/compute-automation-configurations/fdc643759c9aa7e9259da10575e67dc1368e4e9f/prepare_vm_disks.ps1
Add this script extension to the extensionProfile of the virtualMachineProfile of the scale set:
{
"name": "customScript",
"properties": {
"publisher": "Microsoft.Compute",
"type": "CustomScriptExtension",
"typeHandlerVersion": "1.8",
"autoUpgradeMinorVersion": true,
"settings": {
"fileUris": [
"https://https://raw.githubusercontent.com/Azure-Samples/compute-automation-configurations/fdc643759c9aa7e9259da10575e67dc1368e4e9f/prepare_vm_disks.ps1"
],
"commandToExecute": "powershell -ExecutionPolicy Unrestricted -File prepare_vm_disks.ps1"
}
}
}

Answer 2

As the MS guide template, you need to include a dataDisks section in the storageProfile of the Microsoft.Compute/virtualMachineScaleSets resource(s) and deploy the template.
Here is a working template for your references:
{
"$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"vmSku": {
"type": "string",
"defaultValue": "Standard_A1_v2",
"metadata": {
"description": "Size of VMs in the VM Scale Set."
}
},
"windowsOSVersion": {
"type": "string",
"defaultValue": "2016-Datacenter"
},
"vmssName": {
"type": "string",
"minLength": 3,
"maxLength": 61
},
"instanceCount": {
"type": "int",
"defaultValue": 3,
"minValue": 1,
"maxValue": 100,
"metadata": {
"description": "Number of VM instances (100 or less)."
}
},
"singlePlacementGroup": {
"type": "bool",
"defaultValue": true
},
"adminUsername": {
"type": "string",
"defaultValue": "vmssadmin"
},
"adminPassword": {
"type": "securestring"
},
"location": {
"type": "string",
"defaultValue": "[resourceGroup().location]"
},
"platformFaultDomainCount": {
"type": "int",
"defaultValue": 1
}
},
"variables": {
"namingInfix": "[toLower(substring(concat(parameters('vmssName'), uniqueString(resourceGroup().id)), 0, 9))]",
"longNamingInfix": "[toLower(parameters('vmssName'))]",
"addressPrefix": "10.0.0.0/16",
"subnetPrefix": "10.0.0.0/24",
"virtualNetworkName": "[concat(variables('namingInfix'), 'vnet')]",
"publicIPAddressName": "[concat(variables('namingInfix'), 'pip')]",
"subnetName": "[concat(variables('namingInfix'), 'subnet')]",
"loadBalancerName": "[concat(variables('namingInfix'), 'lb')]",
"publicIPAddressID": "[resourceId('Microsoft.Network/publicIPAddresses',variables('publicIPAddressName'))]",
"lbProbeID": "[resourceId('Microsoft.Network/loadBalancers/probes',variables('loadBalancerName'), 'tcpProbe')]",
"natPoolName": "[concat(variables('namingInfix'), 'natpool')]",
"bePoolName": "[concat(variables('namingInfix'), 'bepool')]",
"lbPoolID": "[resourceId('Microsoft.Network/loadBalancers/backendAddressPools',variables('loadBalancerName'),variables('bePoolName'))]",
"natStartPort": 50000,
"natEndPort": 50119,
"natBackendPort": 3389,
"nicName": "[concat(variables('namingInfix'), 'nic')]",
"ipConfigName": "[concat(variables('namingInfix'), 'ipconfig')]",
"frontEndIPConfigID": "[resourceId('Microsoft.Network/loadBalancers/frontendIPConfigurations',variables('loadBalancerName'),'loadBalancerFrontEnd')]",
"osType": {
"publisher": "MicrosoftWindowsServer",
"offer": "WindowsServer",
"sku": "[parameters('windowsOSVersion')]",
"version": "latest"
},
"imageReference": "[variables('osType')]"
},
"resources": [
{
"type": "Microsoft.Network/loadBalancers",
"apiVersion": "2020-06-01",
"name": "[variables('loadBalancerName')]",
"location": "[parameters('location')]",
"dependsOn": [
"[resourceId('Microsoft.Network/publicIPAddresses', variables('publicIPAddressName'))]"
],
"properties": {
"frontendIPConfigurations": [
{
"name": "LoadBalancerFrontEnd",
"properties": {
"publicIPAddress": {
"id": "[variables('publicIPAddressID')]"
}
}
}
],
"backendAddressPools": [
{
"name": "[variables('bePoolName')]"
}
],
"inboundNatPools": [
{
"name": "[variables('natPoolName')]",
"properties": {
"frontendIPConfiguration": {
"id": "[variables('frontEndIPConfigID')]"
},
"protocol": "Tcp",
"frontendPortRangeStart": "[variables('natStartPort')]",
"frontendPortRangeEnd": "[variables('natEndPort')]",
"backendPort": "[variables('natBackendPort')]"
}
}
],
"loadBalancingRules": [
{
"name": "LBRule",
"properties": {
"frontendIPConfiguration": {
"id": "[variables('frontEndIPConfigID')]"
},
"backendAddressPool": {
"id": "[variables('lbPoolID')]"
},
"protocol": "Tcp",
"frontendPort": 80,
"backendPort": 80,
"enableFloatingIP": false,
"idleTimeoutInMinutes": 5,
"probe": {
"id": "[variables('lbProbeID')]"
}
}
}
],
"probes": [
{
"name": "tcpProbe",
"properties": {
"protocol": "Tcp",
"port": 80,
"intervalInSeconds": 5,
"numberOfProbes": 2
}
}
]
}
},
{
"type": "Microsoft.Compute/virtualMachineScaleSets",
"apiVersion": "2020-06-01",
"name": "[variables('namingInfix')]",
"location": "[parameters('location')]",
"sku": {
"name": "[parameters('vmSku')]",
"tier": "Standard",
"capacity": "[parameters('instanceCount')]"
},
"dependsOn": [
"[resourceId('Microsoft.Network/loadBalancers', variables('loadBalancerName'))]",
"[resourceId('Microsoft.Network/virtualNetworks', variables('virtualNetworkName'))]"
],
"properties": {
"overprovision": true,
"upgradePolicy": {
"mode": "Automatic"
},
"singlePlacementGroup": "[parameters('singlePlacementGroup')]",
"platformFaultDomainCount": "[parameters('platformFaultDomainCount')]",
"virtualMachineProfile": {
"storageProfile": {
"osDisk": {
"caching": "ReadWrite",
"createOption": "FromImage"
},
"dataDisks": [
{
"diskSizeGB": 128,
"lun": 0,
"createOption": "Empty"
}
],
"imageReference": "[variables('imageReference')]"
},
"osProfile": {
"computerNamePrefix": "[variables('namingInfix')]",
"adminUsername": "[parameters('adminUsername')]",
"adminPassword": "[parameters('adminPassword')]"
},
"networkProfile": {
"networkInterfaceConfigurations": [
{
"name": "[variables('nicName')]",
"properties": {
"primary": true,
"ipConfigurations": [
{
"name": "[variables('ipConfigName')]",
"properties": {
"subnet": {
"id": "[resourceId('Microsoft.Network/virtualNetworks/subnets', variables('virtualNetworkName'), variables('subnetName'))]"
},
"loadBalancerBackendAddressPools": [
{
"id": "[variables('lbPoolID')]"
}
],
"loadBalancerInboundNatPools": [
{
"id": "[resourceId('Microsoft.Network/loadBalancers/inboundNatPools', variables('loadBalancerName'), variables('natPoolName'))]"
}
]
}
}
]
}
}
]
},
"extensionProfile": {
"extensions": [
{
"name": "customScript",
"properties": {
"publisher": "Microsoft.Compute",
"type": "CustomScriptExtension",
"typeHandlerVersion": "1.8",
"autoUpgradeMinorVersion": true,
"settings": {
"fileUris": [
"https://raw.githubusercontent.com/Azure-Samples/compute-automation-configurations/master/prepare_vm_disks.ps1"
],
"commandToExecute": "powershell -ExecutionPolicy Unrestricted -File prepare_vm_disks.ps1"
}
}
}
]
}
}
}
},
{
"type": "Microsoft.Network/publicIPAddresses",
"apiVersion": "2020-06-01",
"name": "[variables('publicIPAddressName')]",
"location": "[parameters('location')]",
"properties": {
"publicIPAllocationMethod": "Static",
"dnsSettings": {
"domainNameLabel": "[variables('longNamingInfix')]"
}
}
},
{
"type": "Microsoft.Network/virtualNetworks",
"apiVersion": "2020-06-01",
"name": "[variables('virtualNetworkName')]",
"location": "[parameters('location')]",
"properties": {
"addressSpace": {
"addressPrefixes": [
"[variables('addressPrefix')]"
]
},
"subnets": [
{
"name": "[variables('subnetName')]",
"properties": {
"addressPrefix": "[variables('subnetPrefix')]"
}
}
]
}
}
],
"outputs": {}
}
If you want to create multiple data disks with the copy function, you can add it like this
"storageProfile": {
"osDisk": {
"caching": "ReadWrite",
"createOption": "FromImage"
},
"copy": [
{
"name": "dataDisks",
"count": "[parameters('numberOfDataDisks')]",
"input": {
"diskSizeGB": 1023,
"lun": "[copyIndex('dataDisks')]",
"createOption": "Empty"
}
}
],
After my validation, after the above deployment finishs, you need to initialize the disk in each instance, then you could get the expected result.
Reference: https://learn.microsoft.com/en-us/azure/virtual-machine-scale-sets/tutorial-use-disks-powershell#prepare-the-data-disks