335 lines
8.1 KiB
Markdown
335 lines
8.1 KiB
Markdown
---
|
|
gitea: none
|
|
title: Flockige Infrastruktur deklarativ
|
|
include_toc: yes
|
|
lang: en
|
|
---
|
|
|
|
# Setup
|
|
|
|
## Add this repo to your local Nix registry
|
|
|
|
As an alternative to a local checkout, always pull the latest code
|
|
from this repo.
|
|
|
|
```bash
|
|
nix registry add c3d2 git+https://gitea.c3d2.de/C3D2/nix-config
|
|
```
|
|
|
|
This enables `nix` commands to find this Flake given the `c3d2#`
|
|
prefix in some arguments.
|
|
|
|
## Working with this repo
|
|
|
|
If you checked out this git repository for working on the code,
|
|
replace `c3d2#` with `.#` and run commands from the repository root.
|
|
|
|
Don't forget to `git add` new files! Flakes require that.
|
|
|
|
## The secrets repo
|
|
|
|
Make sure you have access.
|
|
|
|
## Install Nix Flakes
|
|
|
|
> Nix Flakes ist gegenwärtig bei Nix (Version 20.09) noch keine standardmäßige Funktionalität für Nix. Die Bereitstellung der Kommandos für Nix Flakes müssen als experimentelle Funktionalität für das Kommando ''nix'' festgelegt werden, um sie verfügbar zu machen.
|
|
|
|
Set some configuration (do this only once):
|
|
|
|
```bash
|
|
echo 'experimental-features = nix-command flakes' >> ~/.config/nix/nix.conf
|
|
```
|
|
|
|
### Permanent System with Nix Flakes
|
|
|
|
set this to your NixOS configuration:
|
|
```nix
|
|
{ pkgs, ... }: {
|
|
nix = {
|
|
extraOptions = "experimental-features = nix-command flakes";
|
|
};
|
|
}
|
|
```
|
|
|
|
# Deployment
|
|
|
|
## Deploy a NixOS system from this Flake locally
|
|
|
|
Running `nixos-rebuild --flake c3d2 switch` on a machine should be sufficient
|
|
to update that machine to the current configuration and Nixpkgs revision.
|
|
|
|
## Deploy to a remote NixOS system with this Flake
|
|
|
|
For every host that has a `nixosConfiguration` in our Flake, there are
|
|
two scripts that can be run for deployment via ssh.
|
|
|
|
- `nix run .#glotzbert-nixos-rebuild switch`
|
|
|
|
Copies the current state to build on the target system. This may
|
|
fail due to eg. container resource limits.
|
|
|
|
The target must already be a nixFlakes system.
|
|
|
|
- `nix run .#glotzbert-nixos-rebuild-local switch`
|
|
|
|
Builds locally, then uses `nix copy` to transfer the new NixOS
|
|
system to the target.
|
|
|
|
**Help!** It's needlessly rebuilding stuff that already runs on the
|
|
target? If so, use `nix copy` to transfer where
|
|
`/run/current-system` points to to your build machine.
|
|
|
|
## Remote deployment from non-NixOS
|
|
|
|
A shell script that copies the current working tree, and runs
|
|
`nixos-rebuild switch` on the target:
|
|
|
|
```shell
|
|
./deploy-flake.sh hydra.hq.c3d2.de
|
|
```
|
|
|
|
It cannot not lookup hostnames in `host-registry.nix`. To avoid
|
|
deploying the wrong container on the unrelated DNS records, the script
|
|
always uses the hostname that is already configured on the target
|
|
system.
|
|
|
|
## Checking for updates
|
|
|
|
```shell
|
|
nix run .#list-upgradable
|
|
```
|
|
|
|
|
|
|
|
Checks all hosts with a `nixosConfiguration` in `flake.nix`.
|
|
|
|
## Update from [Hydra build](https://hydra.hq.c3d2.de/jobset/c3d2/nix-config#tabs-jobs)
|
|
|
|
The fastest way to update a system, a manual alternative to setting
|
|
`c3d2.autoUpdate = true;`
|
|
|
|
Just run:
|
|
|
|
```shell
|
|
update-from-hydra
|
|
```
|
|
|
|
## Deploy a MicroVM
|
|
|
|
### Building spaceapi remotely, and deploy
|
|
|
|
```shell
|
|
nix run .#microvm-update-spaceapi
|
|
```
|
|
|
|
### Building spaceapi locally, and deploy
|
|
|
|
```shell
|
|
nix run .#microvm-update-spaceapi-local
|
|
```
|
|
|
|
### Update MicroVM from our Hydra
|
|
|
|
Our Hydra runs `nix flake update` daily in the `updater.timer`,
|
|
pushing it to the `flake-update` branch so that it can build fresh
|
|
systems. This branch is setup as the source flake in all the MicroVMs,
|
|
so the following is all that is needed on a MicroVM-hosting server:
|
|
|
|
```shell
|
|
microvm -Ru $hostname
|
|
```
|
|
|
|
# Cluster deployment with Skyflake
|
|
|
|
## About
|
|
|
|
[Skyflake](https://github.com/astro/skyflake) provides Hyperconverged
|
|
Infrastructure to run NixOS MicroVMs on a cluster. Our setup unifies
|
|
networking with one bridge per VLAN. Persistent storage is replicated
|
|
with Glusterfs.
|
|
|
|
Recognize nixosConfiguration for our Skyflake deployment by the
|
|
`self.nixosModules.cluster-options` module being included.
|
|
|
|
## User interface
|
|
|
|
We use the less-privileged `c3d2@` user for deployment. This flake's
|
|
name on the cluster is `config`. Other flakes can coexist in the same
|
|
user so that we can run separately developed projects like
|
|
*dump-dvb*. *leon* and potentially other users can deploy Flakes and
|
|
MicroVMs without name clashes.
|
|
|
|
### Deploying
|
|
|
|
**git push** this repo to any machine in the cluster, preferably to
|
|
Hydra because there building won't disturb any services.
|
|
|
|
You don't deploy all MicroVMs at once. Instead, Skyflake allows you to
|
|
select NixOS systems by the branches you push to. **You must commit
|
|
before you push!**
|
|
|
|
**Example:** deploy nixosConfigurations `mucbot` and `sdrweb` (`HEAD` is your
|
|
current commit)
|
|
|
|
```bash
|
|
git push c3d2@hydra.serv.zentralwerk.org:config HEAD:mucbot HEAD:sdrweb
|
|
```
|
|
|
|
This will:
|
|
1. Build the configuration on Hydra, refusing the branch update on
|
|
broken builds (through a git hook)
|
|
2. Copy the MicroVM package and its dependencies to the binary cache
|
|
that is accessible to all nodes with Glusterfs
|
|
3. Submit one job per MicroVM into the Nomad cluster
|
|
|
|
*Deleting* a nixosConfiguration's branch will **stop** the MicroVM in Nomad.
|
|
|
|
### Updating
|
|
|
|
**TODO:** how would you like it?
|
|
|
|
### MicroVM status
|
|
|
|
```bash
|
|
ssh c3d2@hydra.serv.zentralwerk.org status
|
|
```
|
|
|
|
## Debugging for cluster admins
|
|
|
|
### Glusterfs
|
|
|
|
Glusterfs holds our MicroVMs' state. They *must always be mounted* or
|
|
brains are split.
|
|
|
|
```bash
|
|
gluster volume info
|
|
gluster volume status
|
|
```
|
|
|
|
#### Restart glusterd
|
|
|
|
```bash
|
|
systemctl restart glusterd
|
|
```
|
|
|
|
#### Remount volumes
|
|
|
|
```bash
|
|
systemctl restart /glusterfs/fast
|
|
systemctl restart /glusterfs/big
|
|
```
|
|
|
|
### Nomad
|
|
|
|
#### Check the cluster state
|
|
|
|
```shell
|
|
nomad server members
|
|
```
|
|
|
|
Nomad *servers* **coordinate** the cluster.
|
|
|
|
Nomad *clients* **run** the tasks.
|
|
|
|
#### Browse in the terminal
|
|
|
|
[wander](https://github.com/robinovitch61/wander) and
|
|
[damon](https://github.com/hashicorp/damon) are nice TUIs that are
|
|
preinstalled on our cluster nodes.
|
|
|
|
#### Browse with a browser
|
|
|
|
First, tunnel TCP port `:4646` from a cluster server:
|
|
|
|
```bash
|
|
ssh -L 4646:localhost:4646 root@server10.cluster.zentralwerk.org
|
|
```
|
|
|
|
Then, visit https://localhost:4646 for for full klickibunti.
|
|
|
|
#### Reset the Nomad state on a node
|
|
|
|
After upgrades, Nomad servers may fail rejoining the cluster. Do this
|
|
to make a *Nomad server* behave like a newborn:
|
|
|
|
```shell
|
|
systemctl stop nomad
|
|
rm -rf /var/lib/nomad/server/raft/
|
|
systemctl start nomad
|
|
```
|
|
|
|
# Secrets management
|
|
|
|
## Secrets managment with PGP
|
|
|
|
Add your gpg-id to the .gpg-id file in secrets and let somebody reencrypt it for you.
|
|
Maybe this works for you, maybe not. I did it somehow:
|
|
|
|
```bash
|
|
PASSWORD_STORE_DIR=`pwd` tr '\n' ' ' < .gpg-id | xargs -I{} pass init {}
|
|
```
|
|
|
|
Your gpg key has to have the Authenticate flag set. If not update it and push it to a keyserver and wait.
|
|
This is necessary, so you can login to any machine with your gpg key.
|
|
|
|
## Secrets Management Using `sops-nix`
|
|
|
|
### Adding a new host
|
|
|
|
Edit `secrets/.sops.yaml`:
|
|
|
|
1. Add an AGE key for this host. Comments in this file tell you how to
|
|
do it.
|
|
2. Add a `creation_rules` section for `host/$host/*yaml` files
|
|
|
|
### Editing a hosts secrets
|
|
|
|
Edit `secrets/.sops.yaml` to add files for a new host and its SSH pubkey.
|
|
|
|
```bash
|
|
# Enter the secrets flake
|
|
cd secrets
|
|
# Get sops
|
|
nix develop
|
|
# Decrypt, start en EDITOR, encrypt
|
|
sops hosts/.../secrets.yaml
|
|
# Push
|
|
git commit -a -m YOLO
|
|
git push origin HEAD:master
|
|
# Go back to this flake
|
|
cd ..
|
|
# Update flake.lock file
|
|
nix flake lock . --update-input secrets
|
|
```
|
|
|
|
# Laptops / Desktops
|
|
|
|
This repository contains a NixOS module that can be used with personal machines
|
|
as well. This module appends `/etc/ssh/ssh_known_hosts` with the host keys of
|
|
registered HQ hosts, and optionally appends `/etc/hosts` with static IPv6
|
|
addresses local to HQ. Simply import the `lib` directory to use the module. As
|
|
an example:
|
|
|
|
```nix
|
|
# /etc/nixos/configuration.nix
|
|
{ config, pkgs, lib, ... }:
|
|
let
|
|
c3d2Config =
|
|
builtins.fetchGit { url = "https://gitea.c3d2.de/C3D2/nix-config.git"; };
|
|
in {
|
|
imports = [
|
|
# ...
|
|
"${c3d2Config}/modules/c3d2.nix"
|
|
];
|
|
|
|
c3d2 = {
|
|
isInHq = false; # not in HQ, this is the default.
|
|
mergeHostsFile = true; # Make entries in /etc/hosts form hosts.nix
|
|
enableMotd = true; # Set the login shell message to the <<</>> logo.
|
|
};
|
|
|
|
# ...
|
|
}
|
|
|
|
```
|