### Using bootc-base-imagectl rechunk

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/bootc-base-imagectl.md

Example command to run the rechunk operation within a container.

```bash
podman run --rm --privileged -v /var/lib/containers:/var/lib/containers quay.io/fedora/fedora-bootc:rawhide \
  bootc-base-imagectl rechunk quay.io/exampleos/exampleos:build quay.io/exampleos/exampleos:latest
```

--------------------------------

### Build and Test Commands

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/CONTRIBUTING.md

Examples of using the 'just' command for building and testing base images with various configurations.

```bash
just build                                    # defaults
TIER=minimal just build                       # different tier
FEDORA_VERSION=43 just test                   # different Fedora version
BUILDER=podman just build                     # use podman instead of buildah
just ci                                       # full CI run (validate + test all tiers)
```

--------------------------------

### Building a Split Image with Chunkah Arguments

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/CONTRIBUTING.md

Example of passing extra arguments to chunkah during the build process.

```bash
BUILDER_EXTRA='--build-arg CHUNKAH_ARGS="--max-layers 128"' just build --chunkah
```

--------------------------------

### Generating a new image using CentOS Stream 10 content from RHEL

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/bootc-base-imagectl.md

This multi-stage Dockerfile example shows how to use CentOS Stream 10 as a repository source and RHEL as a builder image to create a new container image, incorporating custom configurations and systemd units.

```dockerfile
FROM quay.io/centos/centos:stream10 as repos

FROM registry.redhat.io/rhel10/rhel-bootc:10 as builder
RUN --mount=type=bind,from=repos,src=/,dst=/repos,rw /usr/libexec/bootc-base-imagectl build-rootfs --manifest=minimal /repos /target-rootfs

# This container image uses the "artifact pattern"; it has some
# basic configuration we expect to apply to multiple container images.
FROM quay.io/exampleos/baseconfig@sha256:.... as baseconfig

FROM scratch
COPY --from=builder /target-rootfs/ /
# Now we make other arbitrary changes. Copy our systemd units and
# other tweaks from the baseconfig container image.
COPY --from=baseconfig /usr/ /usr/
RUN <<EORUN
set -xeuo pipefail
# Install critical components
dnf -y install linux-firmware NetworkManager cloud-init cowsay
dnf clean all
bootc container lint
EORUN
LABEL containers.bootc 1
ENV container=oci
STOPSIGNAL SIGRTMIN+3
CMD ["/sbin/init"]
```

--------------------------------

### Register New Version in Tenant Configuration

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/RELEASE.md

Example of adding a new version to the kustomization.yaml file in the tenants-config repository.

```yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
  - "rawhide"
  - "44"      # <-- Add new version
  - "43"
  - "42"
```

--------------------------------

### Building against a different Fedora version

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/README.md

This command demonstrates how to build base images for a specific Fedora version by setting the FEDORA_VERSION environment variable and then executing the 'just build' command.

```bash
FEDORA_VERSION=43 just build
```

--------------------------------

### Create Tenant Configuration

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/RELEASE.md

Commands to copy rawhide configuration to a new release version and update version references within YAML files.

```bash
cd cluster/kfluxfedorap01/bootc-tenant/applications/fedora-bootc/
NEW_RELEASE=44

# Copy from rawhide
cp -r rawhide $NEW_RELEASE

# Update version references
sed -i "s/rawhide/$NEW_RELEASE/g" $NEW_RELEASE/**/*.yaml
sed -i "s/compose-rawhide-id/compose-branched-id/" $NEW_RELEASE/releaseplans/release-to-quay-io/kustomization.yaml
```

--------------------------------

### Rechunking an image using chunkah

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/bootc-base-imagectl.md

This command demonstrates how to use the `--chunkah` flag with `rechunk` to process an image using chunkah instead of rpm-ostree, outputting an OCI archive to stdout.

```bash
IMG=quay.io/exampleos/exampleos:latest
podman run --rm --mount=type=image,src=$IMG,dest=/chunkah \
  -e CHUNKAH_CONFIG_STR="$(podman inspect $IMG)" \
  quay.io/fedora/fedora-bootc:rawhide \
  /usr/libexec/bootc-base-imagectl rechunk --chunkah | podman load
```

--------------------------------

### Compose Configuration: Image Build Definition

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/RELEASE.md

Configuration snippet from `pungi-iot/fedora-iot.conf` defining the ostree container build, including the treefile, architectures, and subvariant.

```python
ostree_container = {
    "^IoT$": [
        {
            "config_url": "https://pagure.io/fedora-iot/base-images",
            "config_branch": "main",
            "treefile": "fedora-rawhide.yaml",
            "arches": ["x86_64", "aarch64", "ppc64le", "s390x"],
            "subvariant": "base",           # <-- Used for mapping
            "name": "Fedora-base-bootc",
        },
    ]
}
```

--------------------------------

### Building a Split Image

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/CONTRIBUTING.md

Command to build a split (content-based layered) image using chunkah.

```bash
just build --chunkah
```

--------------------------------

### Build Flow Diagram

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/RELEASE.md

A diagram illustrating the multi-step process of building and releasing bootc base images, from composing images to final output.

```text
┌──────────────────────────────────────────────────────────────────────┐
│ 0. COMPOSE IMAGES                                                    │
│                                                                      │
│    Source: gitlab.com/fedora/bootc/compose-images                    │
│    Output: quay.io/bootc-devel/fedora-bootc-<version>-compose        │
│                                                                      │
│    These images contain the RPM repositories used by base-images.    │
└──────────────────────────────────────────────────────────────────────┘
                              │
                              ▼
┌──────────────────────────────────────────────────────────────────────┐
│ 1. BUILD (triggered by git push or Renovate)                         │
│                                                                      │
│    Source: gitlab.com/fedora/bootc/base-images                       │
│    Pipeline: .tekton/fedora-bootc-*-push.yaml                        │
│    Input: REPOS_IMAGE from compose-images                            │
│                                                                      │
│    Output: quay.io/konflux-fedora/bootc-tenant/                      │
│            fedora-bootc-<version>-<tier>:{{revision}}                │
└──────────────────────────────────────────────────────────────────────┘
                              │
                              ▼ (Konflux creates Snapshot)
┌──────────────────────────────────────────────────────────────────────┐
│ 2. RELEASE (auto-triggered by ReleasePlan)                           │
│                                                                      │
│    ReleasePlan: release-fedora-bootc-to-quay-io                      │
│    Pipeline: push-to-external-registry                               │
└──────────────────────────────────────────────────────────────────────┘
                              │
                              ▼
┌──────────────────────────────────────────────────────────────────────┐
│ 3. OUTPUT                                                            │
│                                                                      │
│    quay.io/bootc-devel/fedora-bootc-<version>-standard               │
│    quay.io/bootc-devel/fedora-bootc-<version>-standard               │
│    quay.io/bootc-devel/fedora-bootc-<version>-minimal                │
│    quay.io/bootc-devel/fedora-bootc-<version>-minimal-plus           │
│    quay.io/bootc-devel/fedora-bootc-<version>-iot                    │
└──────────────────────────────────────────────────────────────────────┘
```

--------------------------------

### Running the tests

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/tests/rootfs/README.md

Builds a test image and then removes it.

```shell
podman build --from localhost/fedora-bootc:latest -t localhost/test-bootc .
podman rmi localhost/test-bootc:latest # Clean up any created images
```

--------------------------------

### Uploader Configuration: Subvariant to Repository Mapping

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/RELEASE.md

Configuration snippet from `ansible/roles/openshift-apps/cloud-image-uploader/templates/config.toml` showing the mapping of the 'base' subvariant to the 'fedora-bootc' repository.

```toml
[consumer_config.container.repos]
base = "fedora-bootc"    # subvariant "base" → repo "fedora-bootc"
IoT = "fedora-iot"
```

--------------------------------

### Uploader Configuration: Target Registries

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/RELEASE.md

Configuration snippet from `ansible/roles/openshift-apps/cloud-image-uploader/templates/config.toml` specifying the target container registries for image uploads.

```toml
[[consumer_config.container.registries]]
url = "registry.fedoraproject.org"

[[consumer_config.container.registries]]
url = "quay.io/fedora"
```

--------------------------------

### Remove Tenant Configuration Directory

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/RELEASE.md

Commands to remove the EOL version directory and update kustomization.yaml in the tenants-config repository.

```bash
cd cluster/kfluxfedorap01/bootc-tenant/applications/fedora-bootc/

# Edit kustomization.yaml to remove "42" from resources

# Delete the version directory
rm -rf 42/
```

--------------------------------

### Remove EOL Release Pipelines from compose-images Repo

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/RELEASE.md

Commands to remove EOL Tekton pipeline configuration files from the compose-images repository.

```bash
cd .tekton/
git rm fedora-bootc-42-compose-*.yaml
```

--------------------------------

### Remove Tekton Pipelines

Source: https://gitlab.com/fedora/bootc/base-images/-/blob/main/RELEASE.md

Commands to remove Tekton pipeline configuration files for an EOL Fedora version from the base-images repository.

```bash
cd .tekton/
git rm fedora-bootc-42-*.yaml
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.