Single node cluster adjustments

Danger

This is not officially supported and I don't regularly test it, I highly recommend using multiple nodes.

Using a single node could lead to data loss unless your backup strategy is rock solid, make sure you are ABSOLUTELY CERTAIN this is what you want.

Update the following changes, then commit and push.

Remove storage redundancy

Set pod counts and number of data copies to 1:

system/rook-ceph/values.yaml

rook-ceph-cluster:
  cephClusterSpec:
    mon:
      count: 1
    mgr:
      count: 1
  cephBlockPools:
    - name: standard-rwo
      spec:
        replicated:
          size: 1
          requireSafeReplicaSize: false
  cephFileSystems:
    - name: standard-rwx
      spec:
        metadataPool:
          replicated:
            size: 1
        dataPools:
          - name: data0
            replicated:
              size: 1
        metadataServer:
          activeCount: 1
          activeStandby: false

Disable automatic upgrade

Because they will try to drain the only node, the pods will have no place to go. Remove them entirely:

rm -rf system/kured

Commit and push the change. You can revert it later when you add more nodes.