content/blog/kubernetes/get_key_and_certificae.md


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---
title: "Get tls certificate and key from a kubernetes secret"
date: 2020-08-06
description: How to extract a tls certificate and keys from a kubernetes secret
tags:
  - k3s
  - kubernetes
---

## The problem

My use case is to deploy a wildcard certificate that was previously handled by an acme.sh on a legacy lxd containers. Since moving to kubernetes parts of my services I have been using cert-manager to issue letsencrypt certificates for the cluster's ingresses. Since I am not done migrating everything yet I need a way of getting a certificate out of kubernetes.

## The solution

Assuming we are working with a secret named `wild.adyxax.org-cert` and our namespace is named `legacy` :
{{< highlight sh >}}
kubectl -n legacy get secret wild.adyxax.org-cert -o json -o=jsonpath="{.data.tls\.crt}" | base64 -d > fullchain.cer
kubectl -n legacy get secret wild.adyxax.org-cert -o json -o=jsonpath="{.data.tls\.key}" | base64 -d > adyxax.org.key
{{< /highlight >}}