71 lines
3.1 KiB
Markdown
71 lines
3.1 KiB
Markdown
# nixos-servers
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Nix definitions to configure our servers at home.
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## Acknowledgements
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- [deploy-rs](https://github.com/serokell/deploy-rs): NixOS deploy tool with rollback functionality
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- [disko](https://github.com/nix-community/disko): declarative disk partitioning
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- [dns.nix](https://github.com/kirelagin/dns.nix): A Nix DSL for defining DNS zones
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- [flake-utils](https://github.com/numtide/flake-utils): Handy utilities to develop Nix flakes
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- [nixos-hardware](https://github.com/NixOS/nixos-hardware): Hardware-specific NixOS modules. Doing the heavy lifting for our Raspberry Pi
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- [kubenix](https://kubenix.org/): declare and deploy Kubernetes resources using Nix
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- [nixhelm](https://github.com/farcaller/nixhelm): Nix-digestible Helm charts
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- [sops-nix](https://github.com/Mic92/sops-nix): Sops secret management for Nix
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## NixOS
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### Prerequisites
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1. Install the Nix package manager or NixOS ([link](https://nixos.org/download))
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2. Enable flake and nix commands ([link](https://nixos.wiki/wiki/Flakes#Enable_flakes_permanently_in_NixOS))
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### Bootstrapping
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We bootstrap our servers using [nixos-anywhere](https://github.com/nix-community/nixos-anywhere).
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This reformats the hard disk of the server and installs a fresh NixOS.
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Additionally, it deploys an age identity, which is later used for decrypting secrets.
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⚠️ This will wipe your server completely ⚠️
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1. Make sure you can decrypt the Sops-encrypted secrets in `secrets/`. You can test this by running `sops -d secrets/serverKeys.yaml`.
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2. Ensure you have root SSH access to the server.
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3. Run nixos-anywhere: `nix run '.#bootstrap' <servername> <hostname>`
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### Deployment
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To deploy all servers at once: `nix run 'nixpkgs#deploy-rs' -- '.#' -k`
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To deploy only one server: `nix run 'nixpkgs#deploy-rs' -- -k --targets '.#<host>'`
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## Kubernetes
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### Prerequisites
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To deploy to the Kubernetes cluster, first make sure you have an admin account on the cluster.
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You can generate this using `nix run '.#gen-k3s-cert' <username> <servername> ~/.kube`, assuming you have SSH access to the master node.
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This puts a private key, signed certificate and a kubeconfig in the kubeconfig directory
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### Bootstrapping
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We are now ready to deploy to the Kubernetes cluster.
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Deployments are done through an experimental Kubernetes feature called [ApplySets](https://kubernetes.io/docs/tasks/manage-kubernetes-objects/declarative-config/#how-to-delete-objects).
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Each applyset is responsible for a set number of resources within a namespace.
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If the cluster has not been initialized yet, we must bootstrap it first.
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Run these deployments:
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- `nix run '.#bootstrap-default'`
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- `nix run '.#bootstrap-kube-system'`
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### Deployment
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Now the cluster has been initialized and we can deploy applications.
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To explore which applications we can deploy, run `nix flake show`.
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Then, for each application, run `nix run '.#<application>'`.
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## Known bugs
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### Rsync not available during bootstrap
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The `rsync` command was removed from recent NixOS ISO which causes nixos-anywhere to fail when copying extra files.
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See [this](https://github.com/nix-community/nixos-anywhere/issues/260) issue.
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Solution is to execute `nix-env -iA nixos.rsync` on the host.
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