Add support for Hetzner

[frafra]

Would it be possible? Hetzner Cloud API supports custom labels.

[tomschlenkhoff]

Would be fantastic, any help needed? Please merge #167

[marco-m]

Although for sure I would appreciate if #167 were merged, I want to point out that it is already possible to, for example, deploy Consul with automatic boostrap and join in Hetzner Cloud. The trick is to use private IP addresses, via what hcloud calls "networks".

To give an idea: from https://registry.terraform.io/providers/hetznercloud/hcloud/latest/docs/resources/server#server-creation-with-network:

Terraform

resource "hcloud_network" "foo" {
  name     = "foo"
  ip_range = "10.0.0.0/8"
}

resource "hcloud_network_subnet" "lab" {
  network_id = hcloud_network.foo.id
  type       = "cloud"
  network_zone = "eu-central"
  ip_range     = "10.0.0.0/24"
}

resource "hcloud_server" "consul" {
  count       = 3
  name        = "consul-${1 + count.index}" # hostname
  ...

  network {
    network_id = hcloud_network.foo.id
    ip         = "10.0.0.${10 + 1 + count.index}"
  }

  depends_on = [
    hcloud_network_subnet.lab
  ]
}

Then start the 3 Consul agents pointing to the same IP address:

consul agent -server -data-dir=/tmp/consul -bootstrap-expect 3 -retry-join=10.0.0.11

:-)

[MagicRB]

While this works, it depends on the first node being online at all times, if that one fails for any reason, now ones won't be able to join so not an ideal solution.

[dverbeek84]

@MagicRB You can also add all the server ip's to the retry-join

[MagicRB]

Yup I realized later that in fact all IPs will work

[ronaldburns]

Updated the implementation of hcloud in go-discover.
Better error handling and location finding.
HBGames/go-discover

Pre-compiled consul binaries are available. Can add 1.13.x versions if requested.
HBGames/consul 1.14.0-beta1