nixos-configuration/README.md

92 lines
3.0 KiB
Markdown
Raw Normal View History

2023-11-17 11:58:33 +00:00
# nixos-configuration
2023-12-08 20:33:53 +00:00
The collection of publically visible nixos-configuration files used for all of
my NixOS machines. Deployment (both local and remote) is managed using
[colmena](https://github.com/zhaofengli/colmena). All machines can be found in
2023-12-10 19:35:32 +00:00
the `flake.nix` file.
2023-12-07 18:29:20 +00:00
## Users
[home-manager](https://nix-community.github.io/home-manager/) configurations
are found in the top-level `users` directory. As of now, there exists settings
for a single user called `jrpotter`.
2023-12-08 20:33:53 +00:00
## Local Machines
2023-12-07 18:29:20 +00:00
My personal laptop configuration is stored in the `hive/framework` directory.
To invoke the equivalent of a local `nixos-rebuild switch` using colmena, run:
2023-12-08 20:33:53 +00:00
```bash
$ colmena apply-local [--sudo]
```
2023-12-08 20:33:53 +00:00
## Remote Machines
2023-12-08 20:33:53 +00:00
Remote machines are hosted on [DigitalOcean](https://www.digitalocean.com/).
The custom images used by each droplet is built by running:
```bash
2023-12-11 12:19:23 +00:00
$ nix build .#digital-ocean.[stoat|tapir]
```
The above command produces an image with root password disabled in favor of SSH.
A droplet running this image will automatically pull in any enabled SSH keys
from your DigitalOcean account at creation time.
### Deployment
Like our local configurations, remote updates are managed by `colmena`.
`colmena` requires non-interactively connecting over the `ssh-ng` protocol
meaning you must add the appropriate private SSH key to an `ssh-agent` before
deploying:
```bash
$ eval $(ssh-agent -s)
$ ssh-add ~/.ssh/id_ed25519
```
Afterward you can run the following:
```bash
$ colmena apply [--on <hostname>]
```
2023-12-08 16:39:14 +00:00
## Secrets
2023-12-08 20:33:53 +00:00
Secrets are managed via [sops-nix](https://github.com/Mic92/sops-nix). The
top-level `.sops.yaml` configures the `age` keys used to encrypt all secrets.
2023-12-08 21:11:32 +00:00
Once configured, you can create/edit a new secrets file using `sops` like so:
```bash
$ nix-shell -p sops --run "sops <filename>"
```
Keep in mind that `sops-nix` supports YAML, JSON, INI, dotenv and binary at the
moment. What format is used is determined by `<filename>`'s extension.
2023-12-08 20:33:53 +00:00
### Admins
2023-12-08 20:33:53 +00:00
To generate a new user-controlled key, you will need an ed25519 SSH key.
Generate one (if you do not already have one) by running:
2023-12-08 16:39:14 +00:00
```bash
$ ssh-keygen -t ed25519 -C "<email>"
```
2023-12-08 20:33:53 +00:00
You can then generate an `age` secret:
2023-12-08 16:39:14 +00:00
```bash
$ mkdir -p ~/.config/sops/age
$ nix-shell -p ssh-to-age --run \
"ssh-to-age -private-key -i <ssh-file> > ~/.config/sops/age/keys.txt"
```
2023-12-08 20:33:53 +00:00
and find its corresponding public key:
2023-12-08 16:39:14 +00:00
```bash
$ nix-shell -p ssh-to-age --run "ssh-to-age < ~/.ssh/id_ed25519.pub"
```
2023-12-08 20:33:53 +00:00
This public key can then be written into the `.sops.yaml` file.
2023-12-08 16:39:14 +00:00
### Servers
2023-12-08 20:33:53 +00:00
Each machine that needs to decrypt secret files will also need to be registered.
To do so, run:
2023-12-07 21:40:44 +00:00
```bash
2023-12-08 20:33:53 +00:00
$ nix-shell -p ssh-to-age --run 'ssh-keyscan <host> | ssh-to-age'
2023-12-07 21:40:44 +00:00
```
2023-12-08 20:33:53 +00:00
This will look for any SSH host ed25519 public keys and automatically run
2024-01-10 17:45:12 +00:00
through `ssh-to-age`. Include a new top-level `keys` entry in `.sops.yaml` so
that newly created secrets file automatically apply the age keys. For existing
secret files, rotate and add the new age key to them:
```bash
$ sops --in-place --rotate --add-age <value> <secrets-file>
```