Upgrade Assistance: Failed to reindex .kibana

I'm trying to upgrade a single node elk cluster to 6.x. I upgraded elasticsearch, kibana, logstash and x-pack (basic license) to version 5.6.8.
In the reindex helper page, I try to reindex .kibana index, but I'm getting an error after a minute or two:

PUT /api/migration/.kibana-6
{
  "statusCode": 400,
  "error": "Bad Request",
  "message": "Index .kibana-6 already exists.",
  "code": "ERR_INDEX_EXISTS",
  "root_cause": [
    {
      "type": "index_already_exists_exception",
      "reason": "index [.kibana-6/lnGEMacMTRKcahTwHeqBwQ] already exists",
      "index_uuid": "lnGEMacMTRKcahTwHeqBwQ",
      "index": ".kibana-6"
    }
  ],
  "type": "index_already_exists_exception",
  "reason": "index [.kibana-6/lnGEMacMTRKcahTwHeqBwQ] already exists",
  "index_uuid": "lnGEMacMTRKcahTwHeqBwQ",
  "index": ".kibana-6",
  "reindexedIndexName": ".kibana-6"
}

The .kibana-6 index is been created immediately after I click the reindex button, but it stays in status red.
Elasticsearch outputs the log after the index creation:

[2018-04-02T15:48:35,972][INFO ][o.e.c.m.MetaDataCreateIndexService] [elk-prod1] [.kibana-6] creating index, cause [api], templates [default], shards [1]/[0], mappings [doc]
[2018-04-02T15:48:35,984][INFO ][o.e.c.r.a.AllocationService] [elk-prod1] Cluster health status changed from [YELLOW] to [RED] (reason: [index [.kibana-6] created]).

Configurations the cluster has:

  • Disabled all x-pack features that not relevant to the basic license.
  • Created an index template with number_of_replicas: 0 and number_of_shards: 5 settings.

Edit: The .kibana index version is 2040099.

Figured it out, the cluster.routing.allocation.enable option was none for some reason. change it and it worked perfectly.

Thanks for sharing your solution, David!