Question regarding volumeclaim templates and autoscaling policies

Elastic Orchestration Elastic Cloud on Kubernetes (ECK)
1

Hello,

I am slowly wrapping my head around using eck and am not sure about best practices/needed items for using volumeclaim templates alongside autoscaling policies for the elasticsearch portion of my cluster.
Volume claim templates | Elastic Cloud on Kubernetes [2.14] | Elastic seems to describe this as a best practice to use across the board for provisioning suitable storage. However the min/max storage settings in autoscaling Elasticsearch autoscaling | Elastic Cloud on Kubernetes [2.14] | Elastic seem like they would conflict with a static/semistatic claim. Are both to be used? Or does an autoscaling policy preclude the need for a volume claim?

Thank you for your help.

2

The ECK autoscaling controller will update the volume claim you set up initially as it scales your cluster up. So you set up your Elasticsearch cluster with an initial volume size defined through the volumeClaimTemplate and then the autoscaler will adjust the storage size of that claim as needed. But note the following restriction from the documentation:

Scaling the storage size automatically requires the ExpandInUsePersistentVolumes feature to be enabled. It also requires a storage class that supports volume expansion.