Timothy J. Aveni
59 lines
1.8 KiB
Markdown
59 lines
1.8 KiB
Markdown
# NixOS ZFS EC2 AMI Builder
|
|
|
|
This project publishes a matched EC2 AMI artifact:
|
|
|
|
- root volume: bootable NixOS EC2 image
|
|
- secondary volume: preseeded ZFS pool mounted at `/nix`
|
|
|
|
The root snapshot and `/nix` snapshot are registered together in one AMI block
|
|
device mapping. Runtime deployments should consume the AMI ID directly and
|
|
should not independently choose a `/nix` snapshot.
|
|
|
|
The image is intentionally project-agnostic. It provides NixOS, ZFS, SSM,
|
|
flakes, and systemd ordering so the Nix daemon waits for `/nix`.
|
|
|
|
## Publish
|
|
|
|
The normal flow builds on a temporary EC2 instance, so your local machine does
|
|
not need to be the same architecture as the target AMI:
|
|
|
|
```bash
|
|
cd tofu/ami-builder
|
|
./publish-ami.sh --builder-instance-type t4g.large
|
|
```
|
|
|
|
`publish-ami.sh` applies this OpenTofu project to create a temporary builder
|
|
instance and `/nix` volume. The builder user data installs a ZFS-capable NixOS
|
|
boot generation, reboots once, seeds the ZFS `/nix` volume, installs the final
|
|
boot generation that expects `/nix`, and powers off.
|
|
|
|
After the instance is stopped, `publish-ami.sh` creates the final AMI from the
|
|
stopped instance, tags the AMI and snapshots, and writes `artifact.json`.
|
|
|
|
The OpenTofu state in this directory owns only temporary builder resources.
|
|
The published AMI and its snapshots are created by the script and are not in
|
|
OpenTofu state, so `tofu destroy` here can clean up the builder without
|
|
deregistering the AMI.
|
|
|
|
Pass extra OpenTofu variables after `--`:
|
|
|
|
```bash
|
|
./publish-ami.sh --builder-instance-type t4g.large -- \
|
|
-var base_nixos_ami_id=ami-...
|
|
```
|
|
|
|
## Artifact Metadata
|
|
|
|
The final AMI is tagged with:
|
|
|
|
- `Architecture`
|
|
- `InputHash`
|
|
- `BuilderGitRev`
|
|
- `FlakeLockRev`
|
|
- `RootSnapshotId`
|
|
- `NixSnapshotId`
|
|
- `NixosSystemClosure`
|
|
|
|
Do not deregister the AMI or delete either snapshot while runtime deployments
|
|
use it.
|