question

Hi @mzv

You can configure the storage class but it applies to all Cassandra pods. Here is an example:

apiVersion: cassandra.datastax.com/v1beta1
kind: CassandraDatacenter
metadata:
  name: dc2
spec:
  clusterName: example
  serverType: cassandra
  serverVersion: "3.11.7"
  managementApiAuth:
    insecure: {}
  size: 9
  storageConfig:
      cassandraDataVolumeClaimSpec:
        storageClassName: server-storage
        accessModes:
          - ReadWriteOnce
        resources:
          requests:
            storage: 500Gi
  racks:
  - name: r1
    nodeAffinityLabels:
      topology.kubernetes.io/zone: us-east1-a
  - name: r2
    nodeAffinityLabels:
      topology.kubernetes.io/zone: us-east1-b
  - name: r3
    nodeAffinityLabels:
      topology.kubernetes.io/zone: us-east1-c

In general I would advise against using different settings across nodes within a single DC. You will have replicas in each rack. Let's say you used faster storage in r1 and in r2. This could lead to performance problems with replicas in r3.

If you want to use different resources for some nodes, then I would consider putting those nodes into a separate DC.

Cheers

John