karpenter
FIPS 140-3Integration & deliverykarpenter is an efficient node manager for kubernetes clusters
karpenter is an efficient node manager for kubernetes clusters
Pull the latest version of this image from the Ghost registry. Pulling requires authentication — generate a token and run docker login first (see Authentication below).
The Ghost catalog is public to browse, but pulling images requires an account. Generate a pull token below (or from your Account → Tokens page) — you'll get a ready-to-paste docker login command, then docker pull works.
The username is generated automatically (it looks like robot$<project>+<auto-id>, not the name you typed) and is included in the docker login command above. The secret is shown only once when you create the token.
All Ghost images are signed with cosign. Verifying the signature before deployment ensures the image has not been tampered with.
Install cosign via brew install cosign or download from the Sigstore releases page.
Reference this image in your Dockerfile as a base layer:
This is a vendor-built FIPS-enabled image: its cryptography runs on FIPS 140-3 validated modules configured by the upstream vendor. You can inspect the image metadata:
| Standard | FIPS 140-3 |
| Crypto module | Vendor-configured validated modules |
| Cryptography | Validated modules only |
| Use case | Government, regulated industries, compliance workloads |
All examples in this guide use the public image. If you’ve mirrored the repository for your own use (for example, to your Docker Hub namespace), update your commands to reference the mirrored image instead of the public one.
For example:
registry.ghost-prod.alphabravo.io/ghost-base/<repository>:<tag><your-namespace>/dhi-<repository>:<tag>For the examples, you must first use docker login registry.ghost-prod.alphabravo.io to authenticate to the registry to pull the images.
To use the Karpenter hardened image in Kubernetes, update your deployment manifests to reference the hardened image.
Karpenter is deployed as a controller in your cluster, typically through a Helm chart, or you can also apply manifests
directly. Replace <tag> with the desired tag.
For example, in your karpenter-controller.yaml file:
apiVersion: v1
kind: ServiceAccount
metadata:
name: karpenter
namespace: karpenter
imagePullSecrets:
- name: karpenter-regcred
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: karpenter
namespace: karpenter
spec:
selector:
matchLabels:
app.kubernetes.io/name: karpenter
template:
metadata:
labels:
app.kubernetes.io/name: karpenter
spec:
serviceAccountName: karpenter
containers:
- name: controller
image: registry.ghost-prod.alphabravo.io/ghost-base/karpenter:<tag>
Make sure to create an imagePullSecret in the karpenter namespace and attach it to the Karpenter ServiceAccount so
the controller Pod can pull the image from your private repository in Docker Hub.
For more details about using Karpenter, refer to the Karpenter documentation.
| Feature | Non-hardened Karpenter | Docker Hardened Karpenter |
|---|---|---|
| Security | Standard base with common utilities | Minimal, hardened base with security patches |
| Shell access | Full shell (bash/sh) available | No shell in runtime variants |
| Package manager | apt/apk available | No package manager in runtime variants |
| User | Runs as root by default | Runs as nonroot user |
| Attack surface | Larger due to additional utilities | Minimal, only essential components |
| Debugging | Traditional shell debugging | Use Docker Debug or Image Mount for troubleshooting |
Ghost hardened images prioritize security through minimalism:
The hardened images intended for runtime don't contain a shell nor any tools for debugging. Common debugging methods for applications built with Ghost hardened images include:
Docker Debug provides a shell, common debugging tools, and lets you install other tools in an ephemeral, writable layer that only exists during the debugging session.
For example, you can use Docker Debug:
docker debug <image-name>
or mount debugging tools with the Image Mount feature:
docker run --rm -it --pid container:my-container \
--mount=type=image,source=registry.ghost-prod.alphabravo.io/ghost-base/busybox,destination=/dbg,ro \
registry.ghost-prod.alphabravo.io/ghost-base/<image-name>:<tag> /dbg/bin/sh
Ghost hardened images come in different variants depending on their intended use. Image variants are identified by their tag.
Runtime variants are designed to run your application in production. These images are intended to be used either
directly or as the FROM image in the final stage of a multi-stage build. These images typically:
Build-time variants typically include dev in the variant name and are intended for use in the first stage of a
multi-stage Dockerfile. These images typically:
FIPS variants include fips in the variant name and tag. They come in both runtime and build-time variants. These
variants use cryptographic modules that have been validated under FIPS 140, a U.S. government standard for secure
cryptographic operations. For example, usage of MD5 fails in FIPS variants.
To view the image variants and get more information about them, select the Tags tab for this repository, and then select a tag.
Switching to the hardened Karpenter image does not require any special changes. You can use it as a drop-in replacement for the standard Karpenter controller image in your existing workflows and configurations.
public.ecr.aws/karpenter/controller:<tag>registry.ghost-prod.alphabravo.io/ghost-base/karpenter:<tag>While the specific configuration requires no changes, be aware of these general differences in Ghost hardened images:
| Item | Migration note |
|---|---|
| Shell access | No shell in runtime variants, use Docker Debug for troubleshooting |
| Package manager | No package manager in runtime variants |
| Debugging | Use Docker Debug or Image Mount instead of traditional shell debugging |
The hardened images intended for runtime don't contain a shell nor any tools for debugging. The recommended method for debugging applications built with Ghost hardened images is to use Docker Debug to attach to these containers. Docker Debug provides a shell, common debugging tools, and lets you install other tools in an ephemeral, writable layer that only exists during the debugging session.
By default image variants intended for runtime, run as the nonroot user. Ensure that necessary files and directories are accessible to the nonroot user. You may need to copy files to different directories or change permissions so your application running as the nonroot user can access them.
Non-dev hardened images run as a nonroot user by default. As a result, applications in these images can't bind to privileged ports (below 1024) when running in Kubernetes or in Docker Engine versions older than 20.10.
By default, image variants intended for runtime don't contain a shell. Use dev images in build stages to run shell commands and then copy any necessary artifacts into the runtime stage. In addition, use Docker Debug to debug containers with no shell.
Ghost hardened images may have different entry points than images such as Docker Official Images. Use docker inspect
to inspect entry points for Ghost hardened images and update your Dockerfile if necessary.