Send logs to Elasticsearch (including Amazon OpenSearch Service)

The es output plugin, allows to ingest your records into an Elasticsearch database. The following instructions assumes that you have a fully operational Elasticsearch service running in your environment.

Configuration Parameters



IP address or hostname of the target Elasticsearch instance


TCP port of the target Elasticsearch instance



Elasticsearch accepts new data on HTTP query path "/_bulk". But it is also possible to serve Elasticsearch behind a reverse proxy on a subpath. This option defines such path on the fluent-bit side. It simply adds a path prefix in the indexing HTTP POST URI.

Empty string


Set payload compression mechanism. Option available is 'gzip'


Specify the buffer size used to read the response from the Elasticsearch HTTP service. This option is useful for debugging purposes where is required to read full responses, note that response size grows depending of the number of records inserted. To set an unlimited amount of memory set this value to False, otherwise the value must be according to the Unit Size specification.



Newer versions of Elasticsearch allows to setup filters called pipelines. This option allows to define which pipeline the database should use. For performance reasons is strongly suggested to do parsing and filtering on Calyptia Fluent Bit side, avoid pipelines.


Enable AWS Sigv4 Authentication for Amazon OpenSearch Service



Specify the AWS region for Amazon OpenSearch Service


Specify the custom sts endpoint to be used with STS API for Amazon OpenSearch Service


AWS IAM Role to assume to put records to your Amazon cluster


External ID for the AWS IAM Role specified with aws_role_arn


Service name to be used in AWS Sigv4 signature. For integration with Amazon OpenSearch Serverless, set to aoss. See the FAQ section on Amazon OpenSearch Serverless for more information.



If you are using Elastic's Elasticsearch Service you can specify the cloud_id of the cluster running. The Cloud ID string has the format <deployment_name>:<base64_info>. Once decoded, the base64_info string has the format <deployment_region>$<elasticsearch_hostname>$<kibana_hostname>.


Specify the credentials to use to connect to Elastic's Elasticsearch Service running on Elastic Cloud


Optional username credential for Elastic X-Pack access


Password for user defined in HTTP_User


Index name



Type name



Enable Logstash format compatibility. This option takes a boolean value: True/False, On/Off



When Logstash_Format is enabled, the Index name is composed using a prefix and the date, e.g: If Logstash_Prefix is equals to 'mydata' your index will become 'mydata-YYYY.MM.DD'. The last string appended belongs to the date when the data is being generated.



Set a separator between logstash_prefix and date.



Time format (based on strftime) to generate the second part of the Index name.



When Logstash_Format is enabled, each record will get a new timestamp field. The Time_Key property defines the name of that field.



When Logstash_Format is enabled, this property defines the format of the timestamp.



When Logstash_Format is enabled, enabling this property sends nanosecond precision timestamps.



When enabled, it append the Tag name to the record.



When Include_Tag_Key is enabled, this property defines the key name for the tag.



When enabled, generate _id for outgoing records. This prevents duplicate records when retrying ES.



If set, _id will be the value of the key from incoming record and Generate_ID option is ignored.


The write_operation can be any of: create (default), index, update, upsert.



When enabled, replace field name dots with underscore, required by Elasticsearch 2.0-2.3.



Print all elasticsearch API request payloads to stdout (for diag only)



If elasticsearch return an error, print the elasticsearch API request and response (for diag only)



Use current time for index generation instead of message record



When included: the value in the record that belongs to the key will be looked up and over-write the Logstash_Prefix for index generation. If the key/value is not found in the record then the Logstash_Prefix option will act as a fallback. Nested keys are not supported (if desired, you can use the nest filter plugin to remove nesting)


When enabled, mapping types is removed and Type option is ignored. Types are deprecated in APIs in v7.0. This options is for v7.0 or later.



Enables dedicated thread(s) for this output. Default value is set since version 1.8.13. For previous versions is 0.


The parameters index and type can be confusing if you are new to Elastic, if you have used a common relational database before, they can be compared to the database and table concepts. Also see the FAQ below


Elasticsearch output plugin supports TTL/SSL, for more details about the properties available and general configuration, please refer to the TLS/SSL section.


The write_operation can be any of:


create (default)

adds new data - if the data already exists (based on its id), the op is skipped.


new data is added while existing data (based on its id) is replaced (reindexed).


updates existing data (based on its id). If no data is found, the op is skipped.


known as merge or insert if the data does not exist, updates if the data exists (based on its id).

Please note, Id_Key or Generate_ID is required in update, and upsert scenario.

Getting Started

In order to insert records into a Elasticsearch service, you can run the plugin from the command line or through the configuration file:

Command Line

The es plugin, can read the parameters from the command line in two ways, through the -p argument (property) or setting them directly through the service URI. The URI format is the following:


Using the format specified, you could start Calyptia Fluent Bit through:

$ calyptia-fluent-bit -i cpu -t cpu -o es:// \
    -o stdout -m '*'

which is similar to do:

$ calyptia-fluent-bit -i cpu -t cpu -o es -p Host= -p Port=9200 \
    -p Index=my_index -p Type=my_type -o stdout -m '*'

Configuration File

In your main configuration file append the following Input & Output sections. You can visualize this configuration here

    Name  cpu
    Tag   cpu

    Name  es
    Match *
    Port  9200
    Index my_index
    Type  my_type

About Elasticsearch field names

Some input plugins may generate messages where the field names contains dots, since Elasticsearch 2.0 this is not longer allowed, so the current es plugin replaces them with an underscore, e.g:





Elasticsearch rejects requests saying "the final mapping would have more than 1 type"

Since Elasticsearch 6.0, you cannot create multiple types in a single index. This means that you cannot set up your configuration as below anymore.

    Name  es
    Match foo.*
    Index search
    Type  type1

    Name  es
    Match bar.*
    Index search
    Type  type2

If you see an error message like below, you'll need to fix your configuration to use a single type on each index.

Rejecting mapping update to [search] as the final mapping would have more than 1 type

For details, please read the official blog post on that issue.

Elasticsearch rejects requests saying "Document mapping type name can't start with '_'"

Calyptia Fluent Bit v1.5 changed the default mapping type from flb_type to _doc, which matches the recommendation from Elasticsearch from version 6.2 forwards (see commit with rationale). This doesn't work in Elasticsearch versions 5.6 through 6.1 (see Elasticsearch discussion and fix). Ensure you set an explicit map (such as doc or flb_type) in the configuration, as seen on the last line:

    Name  es
    Match *
    Host  vpc-test-domain-ke7thhzoo7jawsrhmm6mb7ite7y.us-west-2.es.amazonaws.com
    Port  443
    Index my_index
    AWS_Auth On
    AWS_Region us-west-2
    tls   On
    Type  doc

Calyptia Fluent Bit + Amazon OpenSearch Service

The Amazon OpenSearch Service adds an extra security layer where HTTP requests must be signed with AWS Sigv4. Calyptia Fluent Bit v1.5 introduced full support for Amazon OpenSearch Service with IAM Authentication.

See here for details on how AWS credentials are fetched.

Example configuration:

    Name  es
    Match *
    Host  vpc-test-domain-ke7thhzoo7jawsrhmm6mb7ite7y.us-west-2.es.amazonaws.com
    Port  443
    Index my_index
    Type  my_type
    AWS_Auth On
    AWS_Region us-west-2
    tls     On

Notice that the Port is set to 443, tls is enabled, and AWS_Region is set.

Calyptia Fluent Bit + Elastic Cloud

Calyptia Fluent Bit supports connecting to Elastic Cloud providing just the cloud_id and the cloud_auth settings. cloud_auth uses the elastic user and password provided when the cluster was created, for details refer to the Cloud ID usage page.

Example configuration:

    Name es
    Include_Tag_Key true
    Tag_Key tags
    tls On
    tls.verify Off
    Suppress_Type_Name On
    cloud_id elastic-obs-deployment:ZXVybxxxxxxxxxxxg==
    cloud_auth elastic:2vxxxxxxxxYV

Validation Failed: 1: an id must be provided if version type or value are set

Since v1.8.2, Calyptia Fluent Bit started using create method (instead of index) for data submission. This makes Calyptia Fluent Bit compatible with Datastream introduced in Elasticsearch 7.9.

If you see action_request_validation_exception errors on your pipeline with Calyptia Fluent Bit >= v1.8.2, you can fix it up by turning on Generate_ID as follows:

    Name es
    Match *
    Generate_ID on

Action/metadata contains an unknown parameter type

Elastic Cloud is now on version 8 so the type option must be removed by setting Suppress_Type_Name On as indicated above.

Without this you will see errors like:

{"error":{"root_cause":[{"type":"illegal_argument_exception","reason":"Action/metadata line [1] contains an unknown parameter [_type]"}],"type":"illegal_argument_exception","reason":"Action/metadata line [1] contains an unknown parameter [_type]"},"status":400}

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