Elasticsearch Sink

The Vector elasticsearch sink batches log events to Elasticsearch via the _bulk API endpoint.

Warnings

Configuration

vector.toml
[sinks.my_sink_id]
type = "elasticsearch" # required
inputs = ["my-source-or-transform-id"] # required
compression = "none" # optional, default
healthcheck = true # optional, default
host = "http://10.24.32.122:9000" # optional, no default
index = "vector-%F" # optional, default
pipeline = "pipeline-name" # optional, no default
  • tableoptional

    auth

    Options for the authentication strategy.

    • stringcommonrequired*

      password

      The basic authentication password.

      • Only required when: strategy = "basic"
      • No default
      • View examples
    • stringenumcommonrequired

      strategy

      The authentication strategy to use.

      • No default
      • Enum, must be one of: "aws" "basic"
      • View examples
    • stringcommonrequired*

      user

      The basic authentication user name.

      • Only required when: strategy = "basic"
      • No default
      • View examples
  • tableoptional

    aws

    Options for the AWS connections.

    • stringcommonoptional

      region

      The AWS region of the target service. This defaults to the region named in the host parameter, or the value of the $AWS_REGION or $AWS_DEFAULT_REGION environment variables if that cannot be determined, or "us-east-1".

      • Only relevant when: strategy = "aws"
      • No default
      • View examples
  • tableoptional

    batch

    Configures the sink batching behavior.

    • uint (bytes)commonoptional

      max_size

      The maximum size of a batch, in bytes, before it is flushed. See Buffers & Batches for more info.

      • Default: 10490000 (bytes)
    • uint (seconds)commonoptional

      timeout_secs

      The maximum age of a batch before it is flushed. See Buffers & Batches for more info.

      • Default: 1 (seconds)
  • tableoptional

    buffer

    Configures the sink specific buffer behavior.

    • uint (events)commonoptional

      max_events

      The maximum number of events allowed in the buffer.

      • Only relevant when: type = "memory"
      • Default: 500 (events)
    • uint (bytes)required*

      max_size

      The maximum size of the buffer on the disk. See Buffers & Batches for more info.

      • Only required when: type = "disk"
      • No default
      • View examples
    • stringenumcommonoptional

      type

      The buffer's type and storage mechanism.

      • Default: "memory"
      • Enum, must be one of: "memory" "disk"
      • View examples
    • stringenumoptional

      when_full

      The behavior when the buffer becomes full.

      • Default: "block"
      • Enum, must be one of: "block" "drop_newest"
      • View examples
  • stringenumcommonoptional

    compression

    The compression strategy used to compress the encoded event data before transmission.

    • WARNING: AWS hosted Elasticsearch is unable to use compression
    • Default: "none"
    • Enum, must be one of: "none" "gzip"
    • View examples
  • stringoptional

    doc_type

    The doc_type for your index data. This is only relevant for Elasticsearch <= 6.X. If you are using >= 7.0 you do not need to set this option since Elasticsearch has removed it.

    • Default: "_doc"
  • tableoptional

    encoding

    Configures the encoding specific sink behavior.

    • [string]optional

      except_fields

      Prevent the sink from encoding the specified labels.

      • No default
      • View examples
    • [string]optional

      only_fields

      Limit the sink to only encoding the specified labels.

      • No default
      • View examples
    • stringenumoptional

      timestamp_format

      How to format event timestamps.

      • Default: "rfc3339"
      • Enum, must be one of: "rfc3339" "unix"
      • View examples
  • tableoptional

    headers

    Options for custom headers.

    • stringcommonrequired

      [header-name]

      A custom header to be added to each outgoing Elasticsearch request.

      • No default
      • View examples
  • boolcommonoptional

    healthcheck

    Enables/disables the sink healthcheck upon start. See Health Checks for more info.

    • Default: true
    • View examples
  • stringcommonoptional

    host

    The host of your Elasticsearch cluster. This should be the full URL as shown in the example.

    • No default
    • View examples
  • stringoptional

    id_key

    The name of the event key that should map to Elasticsearch's _id field. By default, Vector does not set the _id field, which allows Elasticsearch to set this automatically. You should think carefully about setting your own Elasticsearch IDs, since this can hinder perofrmance.

    • No default
    • View examples
  • templateablestringcommonoptional

    index

    Index name to write events to. See Document Conflicts and Template Syntax for more info.

    • Default: "vector-%F"
    • View examples
  • stringcommonoptional

    pipeline

    Name of the pipeline to apply.

    • No default
    • View examples
  • tableoptional

    query

    Custom parameters to Elasticsearch query string.

    • stringcommonrequired

      [parameter-name]

      A custom parameter to be added to each Elasticsearch request.

      • No default
      • View examples
  • tableoptional

    request

    Configures the sink request behavior.

    • uint (requests)commonoptional

      in_flight_limit

      The maximum number of in-flight requests allowed at any given time. See Rate Limits for more info.

      • Default: 5 (requests)
    • uint (seconds)commonoptional

      rate_limit_duration_secs

      The time window, in seconds, used for the rate_limit_num option. See Rate Limits for more info.

      • Default: 1 (seconds)
    • uintcommonoptional

      rate_limit_num

      The maximum number of requests allowed within the rate_limit_duration_secs time window. See Rate Limits for more info.

      • Default: 5
    • uintoptional

      retry_attempts

      The maximum number of retries to make for failed requests. The default, for all intents and purposes, represents an infinite number of retries. See Retry Policy for more info.

      • Default: 18446744073709552000
    • uint (seconds)optional

      retry_initial_backoff_secs

      The amount of time to wait before attempting the first retry for a failed request. Once, the first retry has failed the fibonacci sequence will be used to select future backoffs.

      • Default: 1 (seconds)
    • uint (seconds)optional

      retry_max_duration_secs

      The maximum amount of time, in seconds, to wait between retries.

      • Default: 10 (seconds)
    • uint (seconds)commonoptional

      timeout_secs

      The maximum time a request can take before being aborted. It is highly recommended that you do not lower value below the service's internal timeout, as this could create orphaned requests, pile on retries, and result in duplicate data downstream. See Buffers & Batches for more info.

      • Default: 60 (seconds)
  • tableoptional

    tls

    Configures the TLS options for connections from this sink.

    • stringoptional

      ca_file

      Absolute path to an additional CA certificate file, in DER or PEM format (X.509), or an inline CA certificate in PEM format.

      • No default
      • View examples
    • stringcommonoptional

      crt_file

      Absolute path to a certificate file used to identify this connection, in DER or PEM format (X.509) or PKCS#12, or an inline certificate in PEM format. If this is set and is not a PKCS#12 archive, key_file must also be set.

      • No default
      • View examples
    • stringcommonoptional

      key_file

      Absolute path to a private key file used to identify this connection, in DER or PEM format (PKCS#8), or an inline private key in PEM format. If this is set, crt_file must also be set.

      • No default
      • View examples
    • stringoptional

      key_pass

      Pass phrase used to unlock the encrypted key file. This has no effect unless key_file is set.

      • No default
      • View examples
    • booloptional

      verify_certificate

      If true (the default), Vector will validate the TLS certificate of the remote host.

      • WARNING: Setting this to `false` means the certificate will be loaded and checked for validity, but the handshake will not attempt to verify the certificate. Do NOT set this to `false` unless you understand the risks of not verifying the remote certificate.
      • Default: true
      • View examples
    • booloptional

      verify_hostname

      If true (the default), Vector will validate the configured remote host name against the remote host's TLS certificate. Do NOT set this to false unless you understand the risks of not verifying the remote hostname.

      • Default: true
      • View examples

Env Vars

  • stringoptional

    AWS_ACCESS_KEY_ID

    Used for AWS authentication when communicating with AWS services. See relevant AWS components for more info. See AWS Authentication for more info.

    • No default
    • View examples
  • stringoptional

    AWS_SECRET_ACCESS_KEY

    Used for AWS authentication when communicating with AWS services. See relevant AWS components for more info. See AWS Authentication for more info.

    • No default
    • View examples

Examples

POST <host>/_bulk HTTP/1.1
Host: <host>
Content-Type: application/x-ndjson
Content-Length: <byte_size>
{ "index" : { "_index" : "<index>" } }
<json_encoded_log>
{ "index" : { "_index" : "<index>" } }
<json_encoded_log>
{ "index" : { "_index" : "<index>" } }
<json_encoded_log>

How It Works

AWS Authentication

Vector checks for AWS credentials in the following order:

  1. Environment variables AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY.
  2. The credential_process command in the AWS config file. (usually located at ~/.aws/config)
  3. The AWS credentials file. (usually located at ~/.aws/credentials)
  4. The IAM instance profile. (will only work if running on an EC2 instance with an instance profile/role)

If credentials are not found the healtcheck will fail and an error will be logged.

Obtaining an access key

In general, we recommend using instance profiles/roles whenever possible. In cases where this is not possible you can generate an AWS access key for any user within your AWS account. AWS provides a detailed guide on how to do this.

Buffers & Batches

The elasticsearch sink buffers & batches data as shown in the diagram above. You'll notice that Vector treats these concepts differently, instead of treating them as global concepts, Vector treats them as sink specific concepts. This isolates sinks, ensuring services disruptions are contained and delivery guarantees are honored.

Batches are flushed when 1 of 2 conditions are met:

  1. The batch age meets or exceeds the configured timeout_secs.
  2. The batch size meets or exceeds the configured max_size.

Buffers are controlled via the buffer.* options.

Document Conflicts

Vector batches data flushes it to Elasticsearch's _bulk API endpoint. All events are inserted via the index action. Which, in the case of an conflict (document with the same id), will add or replace the document as necessary.

Environment Variables

Environment variables are supported through all of Vector's configuration. Simply add ${MY_ENV_VAR} in your Vector configuration file and the variable will be replaced before being evaluated.

You can learn more in the Environment Variables section.

GCP Authentication

GCP offers a variety of authentication methods and Vector is concerned with the server to server methods and will find credentials in the following order:

  1. If the credentials_path option is set.
  2. If the GOOGLE_APPLICATION_CREDENTIALS envrionment variable is set.
  3. Finally, Vector will check for an instance service account.

If credentials are not found the healtcheck will fail and an error will be logged.

Health Checks

Health checks ensure that the downstream service is accessible and ready to accept data. This check is performed upon sink initialization. If the health check fails an error will be logged and Vector will proceed to start.

Require Health Checks

If you'd like to exit immediately upon a health check failure, you can pass the --require-healthy flag:

vector --config /etc/vector/vector.toml --require-healthy

Disable Health Checks

If you'd like to disable health checks for this sink you can set the healthcheck option to false.

Rate Limits

Vector offers a few levers to control the rate and volume of requests to the downstream service. Start with the rate_limit_duration_secs and rate_limit_num options to ensure Vector does not exceed the specified number of requests in the specified window. You can further control the pace at which this window is saturated with the in_flight_limit option, which will guarantee no more than the specified number of requests are in-flight at any given time.

Please note, Vector's defaults are carefully chosen and it should be rare that you need to adjust these. If you found a good reason to do so please share it with the Vector team by opening an issue.

Retry Policy

Vector will retry failed requests (status == 429, >= 500, and != 501). Other responses will not be retried. You can control the number of retry attempts and backoff rate with the retry_attempts and retry_backoff_secs options.

TLS

Vector uses Openssl for TLS protocols for it's battle-tested and reliable security. You can enable and adjust TLS behavior via the tls.* options.

Template Syntax

The index options support Vector's template syntax, enabling dynamic values derived from the event's data. This syntax accepts strptime specifiers as well as the {{ field_name }} syntax for accessing event fields. For example:

vector.toml
[sinks.my_elasticsearch_sink_id]
# ...
index = "application-{{ application_id }}-%Y-%m-%d"
index = "vector-%Y-%m-%d"
# ...

You can learn more about the complete syntax in the templating reference.