Cloud

splunk_hec

Publishes messages to a Splunk HTTP Endpoint Collector (HEC).

Performance

This output benefits from sending multiple messages in flight in parallel for improved performance. You can tune the max number of in flight messages (or message batches) with the field max_in_flight.

This output benefits from sending messages as a batch for improved performance. Batches can be formed at both the input and output level. You can find out more in this doc.

Common
Advanced

output:
  label: ""
  splunk_hec:
    url: "" # No default (required)
    token: "" # No default (required)
    gzip: false
    event_host: "" # No default (optional)
    event_source: "" # No default (optional)
    event_sourcetype: "" # No default (optional)
    event_index: "" # No default (optional)
    max_in_flight: 64
    batching:
      count: 0
      byte_size: 0
      period: ""
      check: ""

output:
  label: ""
  splunk_hec:
    url: "" # No default (required)
    token: "" # No default (required)
    gzip: false
    event_host: "" # No default (optional)
    event_source: "" # No default (optional)
    event_sourcetype: "" # No default (optional)
    event_index: "" # No default (optional)
    tls:
      enabled: false
      skip_cert_verify: false
      enable_renegotiation: false
      root_cas: ""
      root_cas_file: ""
      client_certs: []
    max_in_flight: 64
    batching:
      count: 0
      byte_size: 0
      period: ""
      check: ""
      processors: [] # No default (optional)

Fields

`batching`

Configure a batching policy.

Type: object

# Examples:
batching:
  byte_size: 5000
  count: 0
  period: 1s

# ---

batching:
  count: 10
  period: 1s

# ---

batching:
  check: this.contains("END BATCH")
  count: 0
  period: 1m

`batching.byte_size`

The maximum total size (in bytes) that a batch can reach before it is flushed. When the combined size of all messages in the batch reaches or exceeds this limit, the batch is immediately sent to the next stage (such as a processor or output).

Set to 0 to disable size-based batching. When disabled, messages are flushed based on other conditions (such as count or period).

Type: int

Default: 0

`batching.check`

A Bloblang query that returns a boolean value indicating whether a message should end a batch.

Type: string

Default: ""

# Examples:
check: this.type == "end_of_transaction"

`batching.count`

The number of messages at which the batch is flushed. Set to 0 to disable count-based batching.

Type: int

Default: 0

`batching.period`

The length of time after which an incomplete batch is flushed regardless of its size. This field accepts Go duration format strings such as 100ms, 1s, or 5s. Supported time units are ns, us, ms, s, m, and h.

Type: string

Default: ""

# Examples:
period: 1s

# ---

period: 1m

# ---

period: 500ms

`batching.processors[]`

A list of processors to apply to a batch as it is flushed. This allows you to aggregate and archive the batch however you see fit. All resulting messages are flushed as a single batch, so splitting the batch into smaller batches with these processors has no effect.

Type: array<processor>

# Examples:
processors:
  - archive:
      format: concatenate


# ---

processors:
  - archive:
      format: lines


# ---

processors:
  - archive:
      format: json_array

`event_host`

Set the host value to assign to the event data. Overrides existing host field if present.

Type: string

`event_index`

Set the index value to assign to the event data. Overrides existing index field if present.

Type: string

`event_source`

Set the source value to assign to the event data. Overrides existing source field if present.

Type: string

`event_sourcetype`

Set the sourcetype value to assign to the event data. Overrides existing sourcetype field if present.

Type: string

`gzip`

Enable gzip compression

Type: bool

Default: false

`max_in_flight`

The maximum number of messages to have in flight at a given time. For outputs that send messages in batches, this limit applies to message batches. Increase this value to improve throughput.

Type: int

Default: 64

`tls`

Configure Transport Layer Security (TLS) settings to secure network connections. This includes options for standard TLS as well as mutual TLS (mTLS) authentication where both client and server authenticate each other using certificates. Key configuration options include enabled to enable TLS, client_certs for mTLS authentication, root_cas/root_cas_file for custom certificate authorities, and skip_cert_verify for development environments.

Type: object

`tls.client_certs[]`

A list of client certificates for mutual TLS (mTLS) authentication. Configure this field to enable mTLS, authenticating the client to the server with these certificates.

You must set tls.enabled: true for the client certificates to take effect.

Certificate pairing rules: For each certificate item, provide either:

Inline PEM data using both cert and key or
File paths using both cert_file and key_file.

Mixing inline and file-based values within the same item is not supported.

Type: array<object>

Default: []

# Examples:
client_certs:
  - cert: foo
    key: bar


# ---

client_certs:
  - cert_file: ./example.pem
    key_file: ./example.key

`tls.client_certs[].cert`

The plaintext certificate to use for TLS authentication. Must be paired with the corresponding private key in the key field when using inline PEM data for mTLS client certificates.

Type: string

Default: ""

`tls.client_certs[].cert_file`

The path to a file containing the certificate to use for TLS authentication. Must be paired with the corresponding private key file in the key_file field when using file-based configuration for mTLS client certificates.

Type: string

Default: ""

`tls.client_certs[].key`

Private key for mTLS client certificate as inline PEM data. Must correspond to the client certificate specified in the cert field. Use this field together with cert when providing certificate data inline rather than through files.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Manage Secrets before adding it to your configuration.

Type: string

Default: ""

`tls.client_certs[].key_file`

Path to private key file for mTLS client certificate in PEM format. Must correspond to the client certificate specified in the cert_file field. Use this field together with cert_file when loading certificate data from files.

Type: string

Default: ""

`tls.client_certs[].password`

The password to use for the private key (specified in the key or key_file fields), if it is password-protected. The PKCS#1 and PKCS#8 formats are supported. Supports environment variable interpolation for secure password management.

The pbeWithMD5AndDES-CBC algorithm is obsolete and not supported for the PKCS#8 format. This algorithm does not authenticate the ciphertext, making it vulnerable to padding oracle attacks that can let an attacker recover the plaintext.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Manage Secrets before adding it to your configuration.

Type: string

Default: ""

# Examples:
password: foo

# ---

password: ${KEY_PASSWORD}

`tls.enable_renegotiation`

Whether to allow the remote server to repeatedly request renegotiation. Enable this option if you’re seeing the error message local error: tls: no renegotiation.

Type: bool

Default: false

`tls.enabled`

Whether to enable TLS for secure connections. Set to true to enable TLS encryption. Required to be true for other TLS options (like client_certs, root_cas, etc.) to take effect.

Type: bool

Default: false

`tls.root_cas`

Specify a root certificate authority to use (optional). This is a string that represents a certificate chain from the parent-trusted root certificate, through possible intermediate signing certificates, to the host certificate. Use either this field for inline certificate data or root_cas_file for file-based certificate loading.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Manage Secrets before adding it to your configuration.

Type: string

Default: ""

# Examples:
root_cas: |-
  -----BEGIN CERTIFICATE-----
  ...
  -----END CERTIFICATE-----

`tls.root_cas_file`

Specify the path to a root certificate authority file (optional). This is a file, often with a .pem extension, which contains a certificate chain from the parent-trusted root certificate, through possible intermediate signing certificates, to the host certificate. Use either this field for file-based certificate loading or root_cas for inline certificate data.

Type: string

Default: ""

# Examples:
root_cas_file: ./root_cas.pem

`tls.skip_cert_verify`

Whether to skip server-side certificate verification. Set to true only for testing environments as this reduces security by disabling certificate validation. When using self-signed certificates or in development, this may be necessary, but should never be used in production. Consider using root_cas or root_cas_file to specify trusted certificates instead of disabling verification entirely.

Type: bool

Default: false

`token`

A bot token used for authentication.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Manage Secrets before adding it to your configuration.

Type: string

`url`

Full HTTP Endpoint Collector (HEC) URL.

Type: string

# Examples:
url: https://foobar.splunkcloud.com/services/collector/event

Was this helpful?

group Ask in the community

mail Share your feedback

What do you think of this page?

Let us know more:

Let us contact you about your feedback:

splunk_hec

Performance

Fields

batching

batching.byte_size

batching.check

batching.count

batching.period

batching.processors[]

event_host

event_index

event_source

event_sourcetype

gzip

max_in_flight

tls

tls.client_certs[]

tls.client_certs[].cert

tls.client_certs[].cert_file

tls.client_certs[].key

tls.client_certs[].key_file

tls.client_certs[].password

tls.enable_renegotiation

tls.enabled

tls.root_cas

tls.root_cas_file

tls.skip_cert_verify

token

url

`batching`

`batching.byte_size`

`batching.check`

`batching.count`

`batching.period`

`batching.processors[]`

`event_host`

`event_index`

`event_source`

`event_sourcetype`

`gzip`

`max_in_flight`

`tls`

`tls.client_certs[]`

`tls.client_certs[].cert`

`tls.client_certs[].cert_file`

`tls.client_certs[].key`

`tls.client_certs[].key_file`

`tls.client_certs[].password`

`tls.enable_renegotiation`

`tls.enabled`

`tls.root_cas`

`tls.root_cas_file`

`tls.skip_cert_verify`

`token`

`url`