Looking for information on how to implement an Opensearch/Elasticsearch hot/warm/cold infrastructure using Longhorn storage in a Rancher RKE environment. I'm not sure if this is solved by Longhorn or if it's solved in the k8s configuration. If anyone can point me in the right direction, it would be much appreciated.

FWIW - one of my teams manage an ES cluster in K8s by utilizing the ECK operator: https://www.elastic.co/guide/en/cloud-on-k8s/current/k8s-overview.html

Look like you can deploy the ECK operator and provide Longhorn as the StorageClass for the PVC