Ignition Provider for azure ubuntu vm

Question

I am trying to write a systemd service file using ignition provider of terraform like below for ubuntu OS

# Systemd unit data resource containing the unit definition
data "ignition_systemd_unit" "example" {
  name = "example.service"
  content = "[Service]\nType=oneshot\nExecStart=/usr/bin/echo Hello World\n\n[Install]\nWantedBy=multi-user.target"
}

# Ingnition config include the previous defined systemd unit data resource
data "ignition_config" "example" {
  systemd = [
    data.ignition_systemd_unit.example.rendered,
  ]
}

# Create a CoreOS server using the Igntion config.
resource "aws_instance" "web" {
  # ...

  user_data = data.ignition_config.example.rendered
}

and in azurerm_linux_virtual_machine i gave like below

custom_data = data.ignition_config.example.rendered

I am getting an error like below

Error: expected "custom_data" to be a base64 string, got {"ignition":{"config":{},"timeouts":{},"version":"2.1.0"},"networkd":{},"passwd":{},"storage":{},"systemd":{"units":[{"contents":"[Service]\nType=oneshot\nExecStart=/usr/bin/echo Hello World\n\n[Install]\nWantedBy=multi-user.target","enabled":true,"name":"example.service"}]}}

How can i create a systemd service file using terraform and also what am i missing with above config, will this ignition work only with centos ? Any help on this would be appreciated

Answer 1

For the error message, you could use base64encode function to apply Base64 encoding to a string.

 custom_data = base64encode(data.ignition_config.example.rendered)

I tried it with Azure VM image UbuntuServer 16.04-LTS