coredns
CoreDNS Overview
Secure your stack with a hardened CoreDNS image freshly-built by Minimus. Minimus images always include the most up-to-date package version for all packages and dependencies contained in the image.
CoreDNS provides DNS-based service discovery within a Kubernetes cluster, translating service names into IP addresses so Pods can communicate reliably.
Try It Out
This guide will not install CoreDNS with Helm since Minikube already deploys CoreDNS as a core cluster component. We will update the existing Deployment instead of installing a Helm release.
Prerequisites
- A running Kubernetes cluster (v1.21 or higher is recommended)
kubectlinstalled and configured
Step 1: Start Cluster
If you have a cluster to work with, skip this step. Otherwise, start a Minikube cluster. Deployment instructions
Step 2: Override the CoreDNS Image
kubectl -n kube-system set image deployment/coredns \
coredns=reg.mini.dev/coredns:latestVerify the deployment:
kubectl -n kube-system rollout status deployment/corednsWait a minute and check that the Pod is up and running:
kubectl -n kube-system get poConfirm that Minimus images were deployed:
kubectl -n kube-system describe pods | grep Image:Step 3: Clean Up
Roll back using rollout history to reset Minikube to the default CoreDNS image:
kubectl -n kube-system rollout undo deployment/corednsVerify:
kubectl -n kube-system rollout status deployment/corednsTechnical Considerations
The CoreDNS image provided by Minimus is a slim, security-hardened alternative to the public image. The images are largely interchangeable, with a few differences as noted below.
CoreDNS built by Minimus:
- Runs as non-root by default as user 65532. The public image runs as nonroot:nonroot.
- Listens on but does not expose the default port: 53/tcp and 53/udp. The public image exposes those ports by default.
- Drill down on the version specification tab to see the default user, listening ports, entrypoint, volumes, environment variables, etc.
The Payoff
A hardened, minimal image that will remain more secure for the long run and accrue vulnerabilities at a slower rate.
- See the risk reduction dashboard for a detailed CVE comparison over the past 30 days.
- Review the compliance report to see the default hardening and security configurations for the image.
Terms & Info
Trademark
This catalog is published by Minimus. All product names, logos, and marks, other than those belonging to Minimus, shown are owned by their respective rights holders and appear here only to identify the open source software each image contains. Minimus claims no ownership of those marks and implies no affiliation with, endorsement by, certification by, or sponsorship by any rights holder.
Disclaimer
Images are provided "as-is" without warranty of any kind. "Hardened" refers to the security configuration applied at the time of build and does not constitute a guarantee of ongoing security or absence of vulnerabilities. The free tier is provided without support, SLA, or guaranteed patching timelines. Security updates may be applied to paid subscriptions before or instead of free tier images. By pulling or using any image you agree to our Terms of Use.