OpenSearch upgrade leftover persistent settings

Hello,

After OpenSearch upgrade we note that these entries have been added to the persistent settings of the clusters:

{
  "persistent" : {
    "plugins" : {
      "index_state_management" : {
        "metadata_migration" : {
          "status" : "1"
        },
        "template_migration" : {
          "control" : "-1"
        }
      }
    }
...
}

I haven’t found any documentation around them but I guess they were used to coordinate the migration. May I delete them now that clusters are happily upgraded? Is there any documentation around these that I missed? Many thanks in advance.

Have the same question, anybody has more information about this?

following, any updates?

Hi,
I join the question

In a freshly deployed cluster, there is only one option:

GET _cluster/settings?flat_settings
...
{
   "persistent": {
     "plugins.index_state_management.template_migration.control": "-1"
   },
   "transient": {}
}

In the cluster log I constantly see the lines

[2023-03-07T06:31:48,899][INFO ][o.o.a.u.d.DestinationMigrationCoordinator] [node-data201] Detected cluster change event for destination migration
[2023-03-07T06:35:03,630][INFO ][o.o.a.u.d.DestinationMigrationCoordinator] [node-data201] Detected cluster change event for destination migration
[2023-03-07T06:35:04,182][INFO ][o.o.a.u.d.DestinationMigrationCoordinator] [node-data201] Detected cluster change event for destination migration

In existing clusters, two parameters as @spapadop wrote and the same lines in the log, although all nodes have long been updated and work