Searchable Snapshot ILM ERROR

[egalpin]

Hi there,

I'm attempting to make use of the newly GA Frozen phase with searchable_snapshot enabled. I'm consistently getting the following error at the step mount-snapshot of the frozen phase:

index [restored-my-index] in snapshot [found-snapshots/tZiA3xmFTa2Vdbg_vI6c0A:2021.06.16-restored-my-index-my-ilm-policy-_cpxfqelslg61xy-qyqmdq]
is a snapshot of a searchable snapshot index backed by index [my-index]
in snapshot [found-snapshots/tZiA3xmFTa2Vdbg_vI6c0A:2021.06.16-my-index-my-ilm-policy-k35htcclrvgdcn9qzwdcya] and cannot be mounted;
did you mean to restore it instead?

My ILM policy makes use of searchable snapshot in both the cold and the frozen phases. I noticed that the documentation makes it clear that using searchable_snapshot in the hot phase is incompatible with using searchable_snapshot in any other phase[1], but it's not clear whether using searchable_snapshot in cold and frozen is compatible.

Here is my policy definition:

{
  "policy": {
    "phases": {
      "hot": {
        "min_age": "0ms",
        "actions": {
          "set_priority": {
            "priority": 100
          }
        }
      },
      "cold": {
        "min_age": "91d",
        "actions": {
          "searchable_snapshot": {
            "snapshot_repository": "found-snapshots",
            "force_merge_index": true
          },
          "set_priority": {
            "priority": 0
          },
          "allocate": {
            "number_of_replicas": 0
          }
        }
      },
      "frozen": {
        "min_age": "240d",
        "actions": {
          "searchable_snapshot": {
            "snapshot_repository": "found-snapshots",
            "force_merge_index": true
          }
        }
      }
    }
  }
}

Is the error that I'm seeing expected behaviour? Is it possible to use searchable_snapshot in both the cold and frozen ILM phases?

[1] Searchable snapshot | Elasticsearch Guide [master] | Elastic