Docs » Get started with the Splunk Distribution of the OpenTelemetry Collector » Collector components » Collector components: Processors » Redaction processor

Redaction processor ๐Ÿ”—

The Redaction processor is an OpenTelemetry Collector component that deletes span attributes that donโ€™t match a list of allowed span attributes. It also masks span attribute values that match a blocked value list. Span attributes that arenโ€™t on the allowed list are removed before any value checks are done.

The supported pipeline type is traces. See Process your data with pipelines for more information.

Get started ๐Ÿ”—

Follow these steps to configure and activate the component:

  1. Deploy the Splunk Distribution of the OpenTelemetry Collector to your host or container platform:

  1. Configure the processor as described in this doc.

  2. Restart the Collector.

Main configuration ๐Ÿ”—

The following example shows the main configuration settings of the redaction processor:

processors:
  redaction:
    # allow_all_keys is a flag which when set to true, which can disables the
    # allowed_keys list. The list of blocked_values is applied regardless. If
    # you just want to block values, set this to true.
    allow_all_keys: false
    # allowed_keys is a list of span attribute keys that are kept on the span and
    # processed. The list is designed to fail closed. If allowed_keys is empty,
    # no span attributes are allowed and all span attributes are removed. To
    # allow all keys, set allow_all_keys to true.
    allowed_keys:
      - description
      - group
      - id
      - name
    # Ignore the following attributes, allow them to pass without redaction.
    # Any keys in this list are allowed so they don't need to be in both lists.
    ignored_keys:
      - safe_attribute
    # blocked_values is a list of regular expressions for blocking values of
    # allowed span attributes. Values that match are masked
    blocked_values:
      - "4[0-9]{12}(?:[0-9]{3})?" ## Visa credit card number
      - "(5[1-5][0-9]{14})"       ## MasterCard number
    # summary controls the verbosity level of the diagnostic attributes that
    # the processor adds to the spans when it redacts or masks other
    # attributes. In some contexts a list of redacted attributes leaks
    # information, while it is valuable when integrating and testing a new
    # configuration. Possible values:
    # - `debug` includes both redacted key counts and names in the summary
    # - `info` includes just the redacted key counts in the summary
    # - `silent` omits the summary attributes
    summary: debug

Next, include the processor in the required pipelines of the service section of your configuration file:

service:
  pipelines:
    traces:
      processors: [redaction]

How does the processor work? ๐Ÿ”—

Ignored attributes are processed first so theyโ€™re always allowed and never blocked. This field should only be used where you know the data is always safe to send to the telemetry system.

Only span attributes included on the list of allowed keys list are retained. If allowed_keys is empty, then no span attributes are allowed. All span attributes are removed in that case. To keep all span attributes, you should explicitly set allow_all_keys to true.

blocked_values applies to the values of the allowed keys. If the value of an allowed key matches the regular expression for a blocked value, the matching part of the value is then masked with a fixed length of asterisks. For example, if notes is on the list of allowed keys, then the notes span attribute is retained. However, if there is a value such as a credit card number in the notes field that matched a regular expression on the list of blocked values, then that value is masked.

Use cases ๐Ÿ”—

Typical use-cases include:

  • Prevent sensitive fields from accidentally leaking into traces

  • Ensure compliance with legal, privacy, or security requirements

Data protection ๐Ÿ”—

The EU General Data Protection Regulation (GDPR) prohibits the transfer of any personal data like birthdates, addresses, or IP addresses across borders without explicit consent from the data subject. Popular trace aggregation services are located in US, not in EU. You can use the redaction processor to scrub personal data from your data.

PRC legislation prohibits the transfer of geographic coordinates outside of the PRC. Popular trace aggregation services are located in US, not in the PRC. You can use the redaction processor to scrub geographic coordinates from your data.

Payment Card Industry (PCI) Data Security Standards prohibit logging certain things or storing them unencrypted. You can use the redaction processor to scrub them from your traces.

Settings ๐Ÿ”—

The following table shows the configuration options for the redaction processor:

Name

Type

Description

allow_all_keys

bool

Allows all span attribute keys. Set this to true to disable the allowed_keys list. The list of blocked values is applied regardless. If you just want to block values, set this to true.

allowed_keys

string

List of allowed span attribute keys. Span attributes not on the list are removed. The list fails if itโ€™s empty. To allow all keys, you need to set allow_all_keys.

ignored_keys

string

List of span attribute keys that are not redacted. Span attributes in this list are allowed to pass through the filter without being changed or removed.

blocked_values

string

List of regular expressions for blocking values of allowed span attributes. Values that match are masked.

summary

string

Controls the verbosity level of the diagnostic attributes that the processor adds to the spans when it redacts or masks other attributes. In some contexts a list of redacted attributes leaks information, while itโ€™s valuable when integrating and testing a new configuration. Possible values are debug, info, and silent.

Troubleshooting ๐Ÿ”—

If you are a Splunk Observability Cloud customer and are not able to see your data in Splunk Observability Cloud, you can get help in the following ways.

Available to Splunk Observability Cloud customers

Available to prospective customers and free trial users

  • Ask a question and get answers through community support at Splunk Answers .

  • Join the Splunk #observability user group Slack channel to communicate with customers, partners, and Splunk employees worldwide. To join, see Chat groups in the Get Started with Splunk Community manual.

To learn about even more support options, see Splunk Customer Success .