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.
Key | Description | default |
---|---|---|
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 TLS/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:
Please note, Id_Key
or Generate_ID
is required in update, and upsert scenario.
In order to insert records into a Elasticsearch service, you can run the plugin from the command line or through the configuration file:
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 Fluent Bit through:
which is similar to do:
In your main configuration file append the following Input & Output sections. You can visualize this configuration here
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:
becomes
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.
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.
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:
The Amazon OpenSearch Service adds an extra security layer where HTTP requests must be signed with AWS Sigv4. 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:
Notice that the Port
is set to 443
, tls
is enabled, and AWS_Region
is set.
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:
Since v1.8.2, Fluent Bit started using create
method (instead of index
) for data submission. This makes Fluent Bit compatible with Datastream introduced in Elasticsearch 7.9.
If you see action_request_validation_exception
errors on your pipeline with Fluent Bit >= v1.8.2, you can fix it up by turning on Generate_ID
as follows:
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:
The following snippet demonstrates using the namespace name as extracted by the kubernetes
filter as logstash prefix:
For records that do nor have the field kubernetes.namespace_name
, the default prefix, logstash
will be used.
Operation | Description |
---|---|
Host
IP address or hostname of the target Elasticsearch instance
127.0.0.1
Port
TCP port of the target Elasticsearch instance
9200
Path
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
compress
Set payload compression mechanism. Option available is 'gzip'
Buffer_Size
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.
512KB
Pipeline
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 Fluent Bit side, avoid pipelines.
AWS_Auth
Enable AWS Sigv4 Authentication for Amazon OpenSearch Service
Off
AWS_Region
Specify the AWS region for Amazon OpenSearch Service
AWS_STS_Endpoint
Specify the custom sts endpoint to be used with STS API for Amazon OpenSearch Service
AWS_Role_ARN
AWS IAM Role to assume to put records to your Amazon cluster
AWS_External_ID
External ID for the AWS IAM Role specified with aws_role_arn
AWS_Service_Name
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.
es
AWS_Profile
AWS profile name
default
Cloud_ID
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>
.
Cloud_Auth
Specify the credentials to use to connect to Elastic's Elasticsearch Service running on Elastic Cloud
HTTP_User
Optional username credential for Elastic X-Pack access
HTTP_Passwd
Password for user defined in HTTP_User
Index
Index name
fluent-bit
Type
Type name
_doc
Logstash_Format
Enable Logstash format compatibility. This option takes a boolean value: True/False, On/Off
Off
Logstash_Prefix
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.
logstash
Logstash_Prefix_Key
When included: the value of the key in the record will be evaluated as key reference and overrides 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. The parameter is expected to be a record accessor.
Logstash_Prefix_Separator
Set a separator between logstash_prefix and date.
-
Logstash_DateFormat
Time format (based on strftime) to generate the second part of the Index name.
%Y.%m.%d
Time_Key
When Logstash_Format is enabled, each record will get a new timestamp field. The Time_Key property defines the name of that field.
@timestamp
Time_Key_Format
When Logstash_Format is enabled, this property defines the format of the timestamp.
%Y-%m-%dT%H:%M:%S
Time_Key_Nanos
When Logstash_Format is enabled, enabling this property sends nanosecond precision timestamps.
Off
Include_Tag_Key
When enabled, it append the Tag name to the record.
Off
Tag_Key
When Include_Tag_Key is enabled, this property defines the key name for the tag.
_flb-key
Generate_ID
When enabled, generate _id
for outgoing records. This prevents duplicate records when retrying ES.
Off
Id_Key
If set, _id
will be the value of the key from incoming record and Generate_ID
option is ignored.
Write_Operation
The write_operation can be any of: create (default), index, update, upsert.
create
Replace_Dots
When enabled, replace field name dots with underscore, required by Elasticsearch 2.0-2.3.
Off
Trace_Output
Print all elasticsearch API request payloads to stdout (for diag only)
Off
Trace_Error
If elasticsearch return an error, print the elasticsearch API request and response (for diag only)
Off
Current_Time_Index
Use current time for index generation instead of message record
Off
Suppress_Type_Name
When enabled, mapping types is removed and Type
option is ignored. If using Elasticsearch 8.0.0 or higher - it no longer supports mapping types, so it shall be set to On.
Off
Workers
The number of workers to perform flush operations for this output.
2
create (default)
adds new data - if the data already exists (based on its id), the op is skipped.
index
new data is added while existing data (based on its id) is replaced (reindexed).
update
updates existing data (based on its id). If no data is found, the op is skipped.
upsert
known as merge or insert if the data does not exist, updates if the data exists (based on its id).