Modify kibana.yml after deploying Kibana with Helm

If you deploy Kibana using the Elastic helm chart with default values, what you'll find is that you don't have any obvious way to modify the kibana.yml file. For example, if you log into the Kibana pod with

kubectl exec --stdin --tty kibana_podname -- /bin/bash

you'll find that there's no editor available (like vi or even ed). You can cat config/kibana.yml, but the comments state that it is auto-generated. So what are you supposed to do to add an a setting to the file? For example, you might need to add a value for xpack.encryptedSavedObjects.encryptionKey so you can configure alerting.

The solution I came up with is a multi-step process:

1. Get the default values.yaml file for the chart and store that in a file with the command:

helm show values elastic/kibana > /tmp/kibana.yaml

2. Edit that file to add a section for kibana.yml under kibanaConfig. Originally, kibanaConfig is empty (set to {}). You need to change it to be something like:

3. Now (unintuitively at least to me) uninstall the helm chart with:

helm uninstall kibana

4. Then install the helm chart again with:

helm install kibana elastic/kibana -f /tmp/kibana.yaml

And that's it. Your changes will be applied and you're good to go.

I'm pretty sure there's a way to create a configMap and reference it, which would then allow you to just delete the pod to have it re-read the configMap, but I haven't figured out those exact details. Maybe in another post.