terraform-module.hcloud-user-data

Description

The purpose of this module is to provide ready to use user-data file for Hetzner cloud servers with multiple network managers.

All actions taken to create user-data file are based on Hetzner server configuration documentation, Hetzner static ip documentation, cloud-init documentation and my own experience/experiments.

Supported features

• Generating private networks configuration for instance after initial boot ( only dhcp - no support for static interface configuration ). This module use three different ways of managing networks
  • interfaces.d config file - for images:
    • debian-10
    • debian-11
  • Netplan config file - for images:
    • ubuntu-20.04
    • ubuntu-22.04
  • NetworkManager keyfile script - for images:
    • fedora-36
    • fedora-37
    • centos-stream-8
    • centos-stream-9
    • rocky-8
    • rocky-9
• Adding additional users with ssh keys and sudo configuration
• Writing additional entries in /etc/hosts file
• Writing additional files on instance (ex. cron jobs)
• Running additional shell commands on initial boot (ex. docker instalation)
• Adding additional packages to VM
• Setting instance Timezone
• Upgrading all packages
• Rebooting after finishing all cloud-init tasks

Working Features for each image

Please take a look at Known Issues section to read why some of the features are not working on described images.

Tested vms configuration

I have tested this module on below instances types:

• CX11
• CPX11

This module should also work on the rest of standard machines with Local SSD based on avaliable documentation.

This module will not work on:

• Dedicated instances (CCXxx)

Usage example

Example for Debian/Ubuntu with few packages installation:

module "cloud_config_file" {
  source            = "git::git@github.com:wszychta/terraform-module.hcloud-user-data?ref=tags/2.2.0"
  server_type       = "cpx11"
  server_image      = "ubuntu-20.04"
  additional_users  = [
    {
      username = "local"
      sudo_options = "ALL=(ALL) NOPASSWD:ALL"
      ssh_public_keys = [
        "ssh-rsa ..................."
      ]
    }
  ]
  additional_hosts_entries = [
    {
      ip = "192.168.0.4"
      hostnames = [
        "host1.lab.net",
        "host1"
      ]
    },
    {
      ip = "192.168.0.5"
      hostnames = [
        "host2.lab.net",
        "host2"
      ]
    },
  ]
  private_networks_settings = [
    {
      routes = {
        "192.168.0.1" = [
          "192.168.0.0/24",
          "192.168.1.0/24"
          "0.0.0.0/0" # To enable access to public network via NAT
        ]
      }
      nameservers = {
        addresses = [
          "192.168.0.3"
        ]
        search = [
          "lab.net",
        ]
      }
    }
  ]
  additional_run_commands = [
    "echo 'test command'"
  ]
  additional_run_commands = [
    "htop",
    "telnet",
    "nano"
  ]
}

Known Issues

There are no Known Issues known to me for now - please let me know if you will find any.

Internet Access with only private networks defined

To enable access to the internet from instance without public ip addresses there are several things to do:

• Prepare NAT instance with public IP address or PFsense/Opnsense which will have rules for NAT-ing
• Add in Hetzner Cloud Console or via hcloud/terraform tool route 0.0.0.0/0 to previously prepared NAT instance/router
• Add route 0.0.0.0/0 to one of the interfaces defined in private_networks_settings - take a look at the example above
• Add one or more DNS servers to nameservers in private_networks_settings (They can be public ones or private) - take a look at the example above

Variables

list(object({
    username        = string
    sudo_options    = string
    ssh_public_keys = list(string)
}))

list(object({
    network_id    = string
    ip            = string
    alias_ips     = list(string)
    routes        = map(list(string))
    nameservers   = object({
      addresses   = list(string)
      search      = list(string)
    })
})

list(object({
    content     = string
    owner_user  = string
    owner_group = string
    destination = string
    permissions = string
}))

list(object({
    ip        = string
    hostnames    = string
}))

Outputs

Contributing

Bug Reports/Feature Requests

Please use the issues tab to report any bugs or feature requests.

I can't guarantee that I will work on every bug/feature, because this is my side project, but I will try to keep an eye on any created issue.

So if somebody will discover any error please look into Developing section

Supporting development

If you like this module and you haven't started working in Hetzner Cloud you can use my PERSONAL REFERRAL LINK to start working with Hetzner cloud. You will get 20 Euro on start and after spending additional 10 Euro I will get the same amount of money.

Developing

If you have and idea how to improve this module please:

1. Fork this module from master branch
2. Work on your changes inside your fork
3. Create Pull Request on this respository.
4. In my spare time I will look at proposed changes

Copyright

Copyright © 2023 Wojciech Szychta

License

GNU GENERAL PUBLIC LICENSE Version 3