ElasticSearch returns "index not found error" for an index that exists

[RA31]

I have an index pattern "barney", which shows on Kibana Management screen and on Discover. But when I hit the _cat/indices API, it does not show the index pattern in the list of indices returned.

When triggering barney/_search, it returns this error

    {
    "error": {
        "root_cause": [
            {
                "type": "index_not_found_exception",
                "reason": "no such index",
                "resource.type": "index_or_alias",
                "resource.id": "<redacted-uuid>",
                "index_uuid": "_na_",
                "index": "<redacted-uuid>"
            }
        ],
        "type": "index_not_found_exception",
        "reason": "no such index",
        "resource.type": "index_or_alias",
        "resource.id": "<redacted-uuid>",
        "index_uuid": "_na_",
        "index": "<redacted-uuid>"
    },
    "status": 404

If the index exists on Management in Kibana, why does it return an error with the API requests?
The Kibana version being used is 6.4.3.

[leandrojmp (Leandro Pereira)]

Hello and welcome,

Please share what you are seeing in Kibana, share an screenshot that shows the indice exists.

Also, share the return you get when running GET _cat/indices in dev tools.