These docs are for Cribl Edge 4.9 and are no longer actively maintained.

See the latest version (4.13).

Elasticsearch Destination

Cribl Edge can send events to an Elasticsearch cluster using the Bulk API. As of v.3.3, Cribl Edge supports Elastic data streams.

Use the Elastic Cloud Destination if you are exclusively targeting Elastic Cloud and prefer a simpler, optimized configuration process.

Type: Streaming | TLS Support: Configurable | PQ Support: Yes

For an example of using Cribl Edge to parse and enrich inbound events for Elasticsearch, see our Splunk to Elasticsearch topic.

Configure Cribl Edge to Output to Elasticsearch

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1. On the top bar, select Products, and then select Cribl Edge. Under Fleets, select a Fleet. Next, you have two options:
   • To configure via QuickConnect, navigate to Routing > QuickConnect (Stream) or Collect (Edge). Select Add Destination and select the Destination you want from the list, choosing either Select Existing or Add New.
   • To configure via the Routes, select Data > Destinations or More > Destinations (Edge). Select the Destination you want. Next, select Add Destination.
2. In the New Destination modal, configure the following under General Settings:
   • Output ID: Enter a unique name to identify this Elasticsearch Destination definition. If you clone this Destination, Cribl Edge will add -CLONE to the original Output ID.
   • Description: Optionally, enter a description.
   • Load balancing: When enabled (default), lets you specify multiple bulk API URLs and load weights. With the No setting, if you notice that Cribl Edge is not sending data to all possible IP addresses, enable Advanced Settings > Round-robin DNS.
   • Bulk API URL or Cloud ID: Specify either an Elasticsearch cluster or Elastic Cloud deployment to send events to. For an Elasticsearch cluster, enter a URL (for example, http://<myElasticCluster>:9200/_bulk). For an Elastic Cloud deployment, enter its Cloud ID. This setting is not available when Load balancing is enabled.
   • Index or data stream: Enter a JavaScript expression that evaluates to the name of the Elastic data stream or Elastic index where you want events to go. The expression is evaluated for each event, can evaluate to a constant value, and must be enclosed in quotes or backticks. An event’s __index field can overwrite the index or data stream name.
3. Under Authentication, toggle Authentication enabled to Yes to display Authentication method dropdown. Select one of these options:
   • Manual: Enter your credentials directly in the resulting Username and Password fields.
   • Secret: Exposes a Credentials secret drop-down, in which you can select a stored secret that references the credentials described above. A Create link is available to store a new, reusable secret.
   • Manual API Key: Exposes an API key field to directly enter your Elasticsearch API key.
   • Secret API Key: Exposes an API key (text secret) drop-down, in which you can select a stored text secret that references your Elasticsearch API key. A Create link is available to store a new, reusable secret.
4. Next, you can configure the following Optional Settings:
   • Exclude current host IPs: This toggle appears when Load balancing is set to Yes. It determines whether to exclude all IPs of the current host from the list of any resolved hostnames. Defaults to No, which keeps the current host available for load balancing.
   • Type: Specify document type to use for events. An event’s __type field can overwrite this value.
   • Backpressure behavior: Specify whether to block, drop, or queue events when all receivers are exerting backpressure. Defaults to Block.
   • Tags: Optionally, add tags that you can use to filter and group Destinations on the Destinations page. These tags aren’t added to processed events. Use a tab or hard return between (arbitrary) tag names.
5. Optionally, you can adjust the Persistent Queue, Processing, Retries, and Advanced settings outlined in the sections below.
6. Select Save, then Commit & Deploy.

Bulk API URLs

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Use the Bulk API URLs table to specify a known set of receivers on which to load-balance data. To specify more receivers on new rows, click Add URL. Each row provides the following fields:

URL: Specify the URL to an Elastic node to send events to – for example, http://elastic:9200/_bulk

Load weight: Set the relative traffic-handling capability for each connection by assigning a weight (> 0). This column accepts arbitrary values, but for best results, assign weights in the same order of magnitude to all connections. Cribl Edge will attempt to distribute traffic to the connections according to their relative weights.

The final column provides an X button to delete any row from the table.

For details on configuring all these options, see About Load Balancing.

When you first enable load balancing, or if you edit the load weight once your data is load–balanced, give the logic time to settle. The changes might take a few seconds to register.

Persistent Queue Settings

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The Persistent Queue Settings tab displays when the Backpressure behavior option in General settings is set to Persistent Queue. Persistent queue buffers and preserves incoming events when a downstream Destination has an outage or experiences backpressure.

Before enabling persistent queue, learn more about persistent queue behavior and how to optimize it with your system:

• About Persistent Queues
• Optimize Destination Persistent Queues (dPQ)
• Destination Backpressure Triggers

On Cribl-managed Cloud Workers (with an Enterprise plan), this tab exposes only the destructive Clear Persistent Queue button (described at the end of this section). A maximum queue size of 1 GB disk space is automatically allocated per PQ‑enabled Destination, per Worker Process. The 1 GB limit is on outbound uncompressed data, and no compression is applied to the queue.

This limit is not configurable. If the queue fills up, Cribl Stream/Edge will block outbound data. To configure the queue size, compression, queue-full fallback behavior, and other options below, use a hybrid Group.

Mode: Use this menu to select when Cribl Stream/Edge engages the persistent queue in response to backpressure events from this Destination. The options are:

If a Worker/Edge Node starts with an invalid Mode setting, it automatically switches to Error mode. This might happen if the Worker/Edge Node is running a version that does not support other modes (older than 4.9.0), or if it encounters a nonexistent value in YAML configuration files.

Max file size: The maximum data volume to store in each queue file before closing it. Enter a numeral with units of KB, MB, etc. Defaults to 1 MB.

Max queue size: The maximum amount of disk space that the queue can consume on each Worker Process. When the queue reaches this limit, the Destination stops queueing data and applies the Queue‑full behavior. Defaults to 5 GB. This field accepts positive numbers with units of KB, MB, GB, and so on. You can set it as high as 1 TB, unless you’ve configured a different Max PQ size per Worker Process on the Group Settings/Fleet Settings page.

Queue file path: The location for the persistent queue files. Defaults to $CRIBL_HOME/state/queues. Cribl Stream/Edge will append /<worker‑id>/<output‑id> to this value.

Compression: Set the codec to use when compressing the persisted data after closing a file. Defaults to None. Gzip is also available.

Queue-full behavior: Whether to block or drop events when the queue begins to exert backpressure. A queue begins to exert backpressure when the disk is low or at full capacity. This setting has two options:

• Block: The output will refuse to accept new data until the receiver is ready. The system will return block signals back to the sender.
• Drop new data: Discard all new events until the backpressure event has resolved and the receiver is ready.

Backpressure duration Limit: When Mode is set to Backpressure, this setting controls how long to wait during network slowdowns before activating queues. A shorter duration enhances critical data loss prevention, while a longer duration helps avoid unnecessary queue transitions in environments with frequent, brief network fluctuations. The default value is 30 seconds.

Strict ordering: By default, the Yes setting enables FIFO (first in, first out) event forwarding, ensuring Cribl Stream/Edge sends earlier queued events first when receivers recover. The persistent queue flushes every 10 seconds in this mode. Changing the setting to No allows you to prioritize new events over queued events and configure a custom drain rate for the queue. When No is enabled, this option appears:

• Drain rate limit (EPS): Optionally, set a throttling rate (in events per second) on writing from the queue to receivers. (The default 0 value disables throttling.) Throttling the queue drain rate can boost the throughput of new and active connections by reserving more resources for them. You can further optimize Worker startup connections and CPU load in the Group Settings/Fleet Settings > Worker Processes settings.

Clear Persistent Queue: For Cloud Enterprise only, click this button if you want to delete the files that are currently queued for delivery to this Destination. If you click this button, a confirmation modal appears. Clearing the queue frees up disk space by permanently deleting the queued data, without delivering it to downstream receivers. This button only appears after you define the Output ID.

Use the Clear Persistent Queue button with caution to avoid data loss. See Steps to Safely Disable and Clear Persistent Queues for more information.

Processing Settings

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Post‑Processing

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Pipeline: Pipeline to process data before sending the data out using this output.

System fields: A list of fields to automatically add to events that use this output. By default, includes cribl_pipe (identifying the Cribl Edge Pipeline that processed the event). Supports wildcards. Other options include:

• cribl_host – Cribl Edge Node that processed the event.
• cribl_input – Cribl Edge Source that processed the event.
• cribl_output – Cribl Edge Destination that processed the event.
• cribl_route – Cribl Edge Route (or QuickConnect) that processed the event.
• cribl_wp – Cribl Edge Worker Process that processed the event.

Retries

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Honor Retry-After header: Whether to honor a Retry-After header, provided that the header specifies a delay no longer than 180 seconds. Cribl Stream/Edge limits the delay to 180 seconds even if the Retry-After header specifies a longer delay. When enabled, any Retry-After header received takes precedence over all other options configured in the Retries section. When disabled, all Retry-After headers are ignored.

Settings for failed HTTP requests: When you want to automatically retry requests that receive particular HTTP response status codes, use these settings to list those response codes.

For any HTTP response status codes that are not explicitly configured for retries, Cribl Stream/Edge applies the following rules:

Upon receiving a response code that’s on the list, Cribl Stream/Edge first waits for a set time interval called the Pre-backoff interval and then begins retrying the request. Time between retries increases based on an exponential backoff algorithm whose base is the Backoff multiplier, until the backoff multiplier reaches the Backoff limit (ms). At that point, Cribl Stream/Edge continues retrying the request without increasing the time between retries any further.

If the sender (which manages the connection to the Destination) is at capacity, it will not accept any incoming events. These incoming events originate internally from a previous stage of the data flow when Destinations send outbound requests to their respective external services, and they include retry requests and new requests. Any events that were already in transit when the sender reached capacity will continue to be processed downstream.

Sender capacity is freed up when an outgoing request succeeds or encounters a non-retryable error. When the sender has available capacity again, it will resume accepting incoming events. This capacity management is influenced by the number of active connections and configured limits, such as concurrency and buffer sizes. If a Pipeline sends events faster than the Destination can process, the buffers may fill up, leading to backpressure and Sender at capacity warnings. This backpressure prevents the sender from accepting additional requests until capacity is restored.

By default, this Destination has no response codes configured for automatic retries. For each response code you want to add to the list, select Add Setting and configure the following settings:

• HTTP status code: A response code that indicates a failed request, for example 429 (Too Many Requests) or 503 (Service Unavailable).
• Pre-backoff interval (ms): The amount of time to wait before beginning retries, in milliseconds. Defaults to 1000 (one second).
• Backoff multiplier: The base for the exponential backoff algorithm. A value of 2 (the default) means that Cribl Stream/Edge will retry after 2 seconds, then 4 seconds, then 8 seconds, and so on.
• Backoff limit (ms): The maximum backoff interval Cribl Stream/Edge should apply for its final retry, in milliseconds. Default (and minimum) is 10,000 (10 seconds); maximum is 180,000 (180 seconds, or 3 minutes).

Retry timed-out HTTP requests: When you want to automatically retry requests that have timed out, toggle this control on to display the following settings for configuring retry behavior:

• Pre-backoff interval (ms): The amount of time to wait before beginning retries, in milliseconds. Defaults to 1000 (one second).
• Backoff multiplier: The base for the exponential backoff algorithm. A value of 2 (the default) means that Cribl Stream/Edge will retry after 2 seconds, then 4 seconds, then 8 seconds, and so on.
• Backoff limit (ms): The maximum backoff interval Cribl Stream/Edge should apply for its final retry, in milliseconds. Default (and minimum) is 10,000 (10 seconds); maximum is 180,000 (180 seconds, or 3 minutes).

Advanced Settings

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Validate server certs: Reject certificates that are not authorized by a trusted CA (for example, the system’s CA). Defaults to Yes.

Round-robin DNS: Toggle on to enable round-robin DNS lookup across multiple IP addresses, IPv4 and IPv6. When a DNS server resolves a Fully Qualified Domain Name (FQDN) to multiple IP addresses, Cribl Edge will sequentially use each address in the order they are returned by the DNS server for subsequent connection attempts. (This option is visible only when the General Settings > Load balancing option is set to No.)

Compress: Compresses the payload body before sending. Defaults to Yes (recommended).

Request timeout: Amount of time (in seconds) to wait for a request to complete before aborting it. Defaults to 30.

Request concurrency: Maximum number of concurrent requests per Worker Process. When Cribl Edge hits this limit, it begins throttling traffic to the downstream service. Defaults to 5. Minimum: 1. Maximum: 32.

Max body size (KB): Maximum size of the request body before compression. Defaults to 4096 KB. The actual request body size might exceed the specified value because the Destination adds bytes when it writes to the downstream receiver. Cribl recommends that you experiment with the Max body size value until downstream receivers reliably accept all events.

Max events per request: Maximum number of events to include in the request body. The 0 default allows unlimited events.

Flush period (s): Maximum time between requests. Low values could cause the payload size to be smaller than its configured maximum. Defaults to 1.

Extra HTTP headers: Name-value pairs to pass as additional HTTP headers. Values will be sent encrypted.

Extra parameters: Name-value pairs to pass as additional parameters. If you are using Elastic ingest pipelines, specify an extra parameter whose name is pipeline and whose value is the name of your pipeline, similar to these examples.

Elastic version: Determines how to format events. For Elastic Cloud, you must explicitly set version 7.x. For other Elasticsearch clusters, the Auto default will discover the downstream Elasticsearch version automatically, but you have the option to explicitly set version 6.x or 7.x.

Elastic pipeline: To send data to an Elastic Ingest pipeline, optionally enter that pipeline’s name as a constant. Or, enter a JavaScript expression that evaluates outgoing events and sends matching events to the desired Elastic Ingest pipeline(s). Cribl Edge will first interpret your entry as a constant and try to find a matching value in the event. If it finds no matching value, it will evaluate your Elastic pipeline entry as an expression.

For example, the expression sourcetype=='access_common'?'cribl_pipeline':undefined matches events whose sourcetype is access_common, and sends them to an Elastic Ingest pipeline named cribl_pipeline.

You can also specify the name of the pipeline in an event field. For example, myPipelineField would use the value from the event’s myPipelineField property (if present) to identify the Elastic Ingest pipeline to process the event. Alternately, the expression myPipelineField != null ? myPipelineField : undefined would also identify this field. If the event does not contain such a field, myPipelineField != null ? myPipelineField : 'theDefaultIndex' will provide a default index. With this approach, you can override the Elastic Ingest pipeline at the event level.

See also the Elasticsearch Source documentation.

The next two fields appear only when the General Settings > Load balancing option is set to Yes.

DNS resolution period (seconds): Re-resolve any hostnames each time this interval recurs, and pick up destinations from the A records. Defaults to 600 seconds.

Load balance stats period (seconds): Lookback traffic history period. Defaults to 300 seconds.

Include document_id: Toggle this setting to No to omit the document_id field when sending events to an Elastic TSDS (time series data stream).

Write action: Action to use when writing events. Set this option to Create (default) when writing to a data stream, which is append-only. Set this option to Index only when you write directly to an index and need to update existing records. Index will fail if you use it to write to a data stream.

Failed request logging mode: Determines which data is logged when a request fails. Use the drop-down to select one of these options:

• None (default).
• Payload.
• Payload + Headers. Use the Safe Headers field below to specify the headers to log. If you leave that field empty, all headers are redacted, even with this setting.

Safe headers: List the headers you want to log, in plain text.

Environment: If you’re using GitOps, optionally use this field to specify a single Git branch on which to enable this configuration. If empty, the config will be enabled everywhere.

Field Normalization

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When sending data to Elasticsearch, this Destination applies the following field normalization to align with the Elasticsearch schema:

• Renames _time to @timestamp, maintaining millisecond precision.
• Renames host to host.name.

See also our Elasticsearch Source documentation’s Field Normalization section.

Internal Fields

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Cribl Edge uses a set of internal fields to assist in forwarding data to a Destination.

Fields for this Destination:

• __id
• __type
• __index
• __host

Notes on HTTP-Based Outputs

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• To proxy outbound HTTP/S requests, see System Proxy Configuration.

• Cribl Edge will attempt to use keepalives to reuse a connection for multiple requests. After two minutes of the first use, the connection will be thrown away, and a new one will be reattempted. This is to prevent sticking to a particular destination when there is a constant flow of events.

• If the server does not support keepalives (or if the server closes a pooled connection while idle), a new connection will be established for the next request.

• When resolving the Destination’s hostname with load balancing disabled, Cribl Edge will pick the first IP in the list for use in the next connection. Enable Round-robin DNS to better balance distribution of events between Elasticsearch cluster nodes.

Troubleshooting

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The Destination’s configuration modal has helpful tabs for troubleshooting:

Live Data: Try capturing live data to see real-time events as they flow through the Destination. On the Live Data tab, click Start Capture to begin viewing real-time data.

Logs: Review and search the logs that provide detailed information about the delivery process, including any errors or warnings that may have occurred.

Test: Ensures that the Destination is correctly set up and reachable. Verify that sample events are sent correctly by clicking Run Test.

You can also view the Monitoring page that provides a comprehensive overview of data volume and rate, helping you identify delivery issues. Analyze the graphs showing events and bytes in/out over time.