# Infra

This directory contains the definition of [the VMs](machines.md) that host our
infrastructure.

## Provisioning VMs with an initial configuration

NOTE[Niols]: This is very manual and clunky. Two things will happen. In the near
future, I will improve the provisioning script to make this a bit less clunky.
In the far future, NixOps4 will be able to communicate with Proxmox directly and
everything will become much cleaner.

1. Choose names for your VMs. It is recommended to choose `fediXXX`, with `XXX`
   above 100. For instance, `fedi117`.

2. Add a basic configuration for the machine. These typically go in
   `infra/machines/<name>/default.nix`. You can look at other `fediXXX` VMs to
   find inspiration. You probably do not need a `nixos.module` option at this
   point.

2. Add a file for each of those VM's public keys, eg.
   ```
   touch keys/systems/fedi117.pub
   ```
   Those files need to exist during provisioning, but their content matters only
   when updating the machines' configuration.

   FIXME: Remove this step by making the provisioning script not fail with the
   public key does not exist yet.

3. Run the provisioning script:
   ```
   sh infra/proxmox-provision.sh fedi117
   ```
   The script can take several ids at the same time. It requires some
   authentication options and provides several more. See `--help`.

4. (Optional) Add a DNS entry for the machine; for instance `fedi117.abundos.eu
   A 95.215.187.117`.

5. Grab the public host keys for the machines in question, and add it to the
   repository. For instance:
   ```
   ssh fedi117.abundos.eu 'sudo cat /etc/ssh/ssh_host_ed25519_key.pub' > keys/systems/fedi117.pub
   ```

   FIXME: Make the provisioning script do that for us.

7. Regenerate the list of machines:
   ```
   sh infra/machines.md.sh
   ```
   Commit it with the machine's configuration, public key, etc.

8. At this point, the machine contains a very basic configuration that contains
   just enough for it to boot and be reachable. Go on to the next section to
   update the machine and put an actual configuration.

   FIXME: Figure out why the full configuration isn't on the machine at this
   point and fix it.

## Updating existing VM configurations

Their configuration can be updated via NixOps4. Run

```sh
nixops4 deployments list
```

to see the available deployments.
This should be done from the root of the repository,
otherwise NixOps4 will fail with something like:

```
    nixops4 error: evaluation: error:
           … while calling the 'getFlake' builtin

           error: path '/nix/store/05nn7krhvi8wkcyl6bsysznlv60g5rrf-source/flake.nix' does not exist, evaluation: error:
           … while calling the 'getFlake' builtin

           error: path '/nix/store/05nn7krhvi8wkcyl6bsysznlv60g5rrf-source/flake.nix' does not exist
```

Then, given a deployment (eg. `fedi200`), run

```sh
nixops4 apply <deployment>
```

Alternatively, to run the `default` deployment, which contains all the VMs, run

```sh
nixops4 apply
```

## Removing an existing VM

See `infra/proxmox-remove.sh --help`.