Ideally, the definitions for Kubernetes objects are all safely stored in your code repository — you can easily revert back to the previous, working iteration, you can see who changed what, and you’ve got a copy of it all available if super electromagnet man takes a stroll through the data center. Ideally.
Here, in the real world, we took over management of a k8s implementation that’s been in service for about a year now. And, fortunately, the production YAMLs are all in the repo. The development system, on the other hand, isn’t. Logic dictates that the config would be similar, but it’s always good to check.
I wrote a quick script to dump YAML files for all of the configmaps, cron jobs, deployments, horizontal pod autoscaling, jobs, persistent volumes, persistent volume claims, secrets, service accounts, services, and stateful sets.
#!/bin/bash
nsbase="namespace/"
for ns in $(kubectl get namespaces -o=name)
do
ns=${ns#${nsbase}}
for n in $(kubectl get --namespace=$ns -o=name configmap,cronjob,deployment,hpa,job,pv,pvc,secret,serviceaccount,service,statefulset)
do
yamlfile="${ns}/${n}.yaml"
mkdir -p $(dirname ${ns}/${n})
kubectl get --namespace=$ns -o=yaml $n > $yamlfile
done
done
