# 🚀 Provisioning Servers with RailianceHosts

This guide explains **where you declare servers**, **how Terraform uses that declaration**, and **how to provision** (and later destroy) machines on Hetzner.

---

## 🚀 Fast Path: Using the Helper Script

Instead of manually editing `inventory/servers.yaml` and running `make tf-apply`, you can use the convenience script [`scripts/hcloud_new_server.sh`](../scripts/hcloud_new_server.sh).  
This script will:

1. Add the new host entry to `inventory/servers.yaml`
2. Decrypt your Hetzner API token with SOPS
3. Run Terraform (`init/plan/apply`) to provision the server
4. Print the IPv4 address and a ready-to-use SSH command

**Example:**

```bash
scripts/hcloud_new_server.sh core-01 --type cpx11 --region nbg1 --role core
```

This will create a small cpx11 instance in the Nuremberg (nbg1) region, tagged with the role core.
You can then connect directly:

```bash
ssh admin@<printed-ip>
```

👉 The script is optional. You can always manage servers by editing inventory/servers.yaml and running make tf-apply instead.



## 1) Where you define servers

All desired hosts live in **`inventory/servers.yaml`**. Each entry is a simple YAML object with the required attributes:

```yaml
servers:
  - name: core-01
    labels: [core, wireguard, git]
    role: "core"
    region: "nbg1"           # Hetzner location (e.g., nbg1, fsn1, hel1)
    type: "cpx21"            # Hetzner server type/flavor
    image: "ubuntu-24.04"    # OS image slug
    ssh_user: "admin"        # bootstrap user (cloud-init creates this)
```

> Tip: Keep **names stable**. Renaming a server in this file makes Terraform think the old one was destroyed and a new one should be created.

---

## 2) Two ways to add a server

### A) Edit YAML by hand (simple)
Open `inventory/servers.yaml`, add a new entry, save, commit.

### B) Use the helper script (safe & quick)
```bash
# requires scripts/new_host.py
make new-host NAME=web-01 TYPE=cpx21 REGION=nbg1 ROLE=web
# or directly:
python3 scripts/new_host.py --name web-01 --type cpx21 --region nbg1 --role web
```

You can also do **add + provision in one step**:
```bash
scripts/hcloud_new_server.sh web-01 --type cpx21 --region nbg1 --role web
```

---

## 3) How Terraform uses your declaration

The module at `terraform/hetzner/`:
- Reads `inventory/servers.yaml` (`for_each` over `servers`)
- Registers your SSH key from `keys/admin_ssh.pub`
- Injects **cloud-init** that sets up the `admin` user and basic hardening
- Creates/updates/destroys servers to match the YAML

Outputs include a map of server names → IPv4 addresses.

---

## 4) Provision (create/update)

Make sure your Hetzner API token is present and **SOPS-decryptable** in `inventory/group_vars/secrets.sops.yaml` under `ops.hcloud_token`.

Then run either:
```bash
# plan and apply in separate steps
make tf-plan
make tf-apply
```
or the end-to-end convenience:
```bash
make apply    # terraform apply + ansible bootstrap
```

If you used the one-shot script:
```bash
scripts/hcloud_new_server.sh web-01 --type cpx21 --region nbg1 --role web
```

Terraform will print the new servers’ IPv4 addresses at the end.

---

## 5) Connect & converge

Connect via SSH:
```bash
ssh admin@<server-ip>
```

Run Ansible base bootstrap (if not using `make apply`):
```bash
make ansible-bootstrap
```

---

## 6) Destroy (tear down)

To remove all servers managed by this repo:
```bash
make tf-destroy
```

To remove just one server, delete its entry from `inventory/servers.yaml`, commit, then:
```bash
make tf-apply
```
Terraform will destroy the missing server and leave others intact.

---

## 7) Notes & conventions

- **Idempotent:** You can run `make apply` repeatedly; Terraform converges infra, Ansible converges config.
- **SSH keys:** Ensure `keys/admin_ssh.pub` exists before provisioning.
- **Secret token:** The Hetzner API token must be in `inventory/group_vars/secrets.sops.yaml` (encrypted with SOPS).
- **Cloud-init delay:** Allow ~30–60s after creation for first-boot tasks before first SSH.
- **Labels & role:** `labels` are freeform tags; `role` can drive Ansible plays as you grow.