> For the complete documentation index, see [llms.txt](https://docs.elastiflow.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.elastiflow.com/additional-resources-reference-articles/faq/elasticsearch_auth_fail.md).

# Elasticsearch Authentication Failure

The collector’s log indicates `failed to bootstrap elasticsearch` and `unable to authenticate user [<username>] for REST request`

### SYMPTOM

The collector's log indicates a message similar to the following:

```log
2023-09-23T18:05:19.604Z        error   bootstrapper[elasticsearch]     elasticsearch/bootstrap.go:147  failed to bootstrap elasticsearch. retrying...  {"code": "elasticsearch/bootstrap-failure", "reason": "error while creating default ilm policy - GET ilm policy error for ilm policy 'elastiflow'- status code 401 not expected - {\"error\":{\"header\":{\"WWW-Authenticate\":[\"Basic realm=\\\"security\\\" charset=\\\"UTF-8\\\"\",\"Bearer realm=\\\"security\\\"\",\"ApiKey\"]},\"reason\":\"unable to authenticate user [xxxxZZelastic] for REST request [/_ilm/policy/elastiflow]\",\"root_cause\":[{\"header\":{\"WWW-Authenticate\":[\"Basic realm=\\\"security\\\" charset=\\\"UTF-8\\\"\",\"Bearer realm=\\\"security\\\"\",\"ApiKey\"]},\"reason\":\"unable to authenticate user [xxxxZZelastic] for REST request [/_ilm/policy/elastiflow]\",\"type\":\"security_exception\"}],\"type\":\"security_exception\"},\"status\":401}"}
github.com/elastiflow/flowcoll/pkg/outputs/elasticsearch.(*Bootstrap).Run
        /tmp/flowcoll/pkg/outputs/elasticsearch/bootstrap.go:147
github.com/elastiflow/flowcoll/pkg/outputs/elasticsearch.NewCreateInstanceFunc.func1
        /tmp/flowcoll/pkg/outputs/elasticsearch/instance_registration.go:155
github.com/elastiflow/flowcoll/pkg/instantiator.(*Instantiator).Run
        /tmp/flowcoll/pkg/instantiator/instantiator.go:79
```

### PROBLEM

The collector's Elasticsearch output is unable to authenticate with the Elasticsearch host(s) specified in `EF_OUTPUT_ELASTICSEARCH_ADDRESSES`.

### SOLUTION

Ensure that `EF_OUTPUT_ELASTICSEARCH_USERNAME` or `EF_OUTPUT_ELASTICSEARCH_PASSWORD` has been entered correctly. Providing the correct username and password will correct this error. You can test the username and password manually using `curl`. For example:

```shell
curl -XGET https://127.0.0.1:9200/_cat/indices -u username:password --insecure
```

### REFERENCE

* [EF\_OUTPUT\_ELASTICSEARCH\_USERNAME](https://github.com/elastiflow/documentation/blob/main/docs/config_ref/common/output_elasticsearch/README.md#ef_output_elasticsearch_username)
* [EF\_OUTPUT\_ELASTICSEARCH\_PASSWORD](https://github.com/elastiflow/documentation/blob/main/docs/config_ref/common/output_elasticsearch/README.md#ef_output_elasticsearch_password)


---

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