Packer input template

template.json

{
    "variables": {
        "client_id": null,
        "client_secret": null,
        "subscription_id": null
    },
    "builders": [
        {
            "type": "azure-arm",
            "subscription_id": "{{user `subscription_id`}}",
            "client_id": "{{user `client_id`}}",
            "client_secret": "{{user `client_secret`}}",
            "resource_group_name": "somergname",
            "storage_account": "somesgacc",
            "capture_container_name": "somecontainername",
            "capture_name_prefix": "somecapnameprefix",
            "location": "westeurope",
            "os_type": "Linux",
            "os_disk_size_gb": 32,
            "image_publisher": "Canonical",
            "image_offer": "UbuntuServer",
            "image_sku": "16.04.0-LTS",
            "vm_size": "Standard_D2_v2",
            "ssh_username": "ubuntu"
        }
    ],
    "provisioners": [
        {
            "type": "shell",
            "pause_before": "30s",
            "inline_shebang": "/bin/bash -ex",
            "inline": [
                "# Clean the system and make it suitable for reprovisioning",
                "sudo -E waagent -verbose -force -deprovision+user"
            ]
        }
    ]
}