These docs are for Cribl Edge 4.8 and are no longer actively maintained.
See the latest version (4.13).
Microsoft Sentinel Destination
Cribl Edge can send log and metric events to the Microsoft Sentinel SIEM. This Destination encrypts and sends events via the HTTPS protocol. The supported environments include:
- Azure Public Cloud
- Azure US Government Cloud
- Microsoft Azure operated by 21Vianet
Type: Streaming | TLS Support: No | PQ Support: Yes
For a walk-through of configuring this Destination with Microsoft Sentinel, see our Microsoft Sentinel SIEM Integration guide. Also see these Packs on the Cribl Packs Dispensary, which provide processing Pipelines that you can import and adapt to your needs:
Ensure that the field names in your data match the schema defined in the Data Collection Rule (DCR) for Microsoft Sentinel. The DCR specifies the expected structure, including field names and types. Mismatched field names can result in dropped events.
Prerequisites
Before configuring your Microsoft Sentinel Destination(s), you have to prepare the Azure workspace, create data collection rules (DCRs), and obtain the ingestion URL that will receive the data from your Destination(s).
Complete these preparatory steps, which are described in Microsoft Sentinel Integration, before configuring the Microsoft Sentinel Destination. That topic explains the overall Sentinel/Cribl workflow, provides necessary context, and shows you how to obtain the values you’ll need to configure the Destination.
Behind the scenes, this Destination uses the Azure Monitor Logs Ingestion API.
Configuring Cribl Edge to Output to Microsoft Sentinel
From the top nav, click Manage, then select a Fleet to configure. Next, you have two options:
- To configure via QuickConnect, click Routing then QuickConnect (Cribl Stream) or Collect (Cribl Edge). Next, click Add Destination and from the resulting drawer’s tiles, select Microsoft Sentinel. Next, click either Add Destination or (if displayed) Select Existing.
- To configure via the Routes, click Data then Destinations (Cribl Stream) or More then Destinations (Cribl Edge). Select Microsoft Sentinel from the list of tiles or the Destinations list. Next, click Add Destination to open a New Destination modal.
If you intend to send multiple event types, or tables, to Sentinel, you’ll need a separate Destination for each event type. There are three approaches to configure this:
- Multiple Destinations: Configure separate Microsoft Sentinel Destinations, each with its own URL, and use Routes to direct data to the appropriate Destination.
- Multiple Destinations and a Output Router: Use an Output Router to split events from a single Source into multiple Destinations, each corresponding to a specific table.
- Single Destination and overwriting the URL in a Pipeline: Configure a single Microsoft Sentinel Destination and dynamically overwrite the URL within Pipelines using the
__urlinternal field to direct events to the correct table.
General Settings
Output ID: Enter a unique name to identify this HTTP output definition. If you clone this Destination, Cribl Edge will add -CLONE to the original Output ID.
Endpoint configuration: Method for configuring the endpoint. Options include:
URL – lets you directly enter the data collection endpoint. This method is the simplest way of configuring the endpoint. See Obtaining a URL for more information.
ID – lets you enter individual IDs that Cribl Edge uses to create the URL used as the data collection endpoint.
Selecting URL exposes the following field.
URL: Endpoint URL to send events to. The internal field __url, where present in events, will override the URL and ID values. See Internal Fields below.
Selecting ID exposes the following fields.
Data collection endpoint: Data collection endpoint (DCE) in the format https://<endpoint-name>.<identifier>.<region>.ingest.monitor.azure.com.
Data collection rule ID: Immutable ID for the data collection rule (DCR).
Stream name: Name of the Sentinel table in which to store events.
Optional Settings
Backpressure behavior: Whether to block, drop, or queue events when all receivers are exerting backpressure.
Tags: Optionally, add tags that you can use to filter and group Destinations in Cribl Edge’s Manage Destinations page. These tags aren’t added to processed events. Use a tab or hard return between (arbitrary) tag names.
Authentication Settings
Login URL: Endpoint for the OAuth API call. This URL varies depending on your Azure environment:
- Azure Public Cloud:
https://login.microsoftonline.com/<tenant-id>/oauth2/v2.0/token - Azure US Government Cloud:
https://login.microsoftonline.us/<tenant-id>/oauth2/v2.0/token - Microsoft Azure operated by 21Vianet:
https://login.chinacloudapi.cn/<tenant-id>/oauth2/v2.0/token
OAuth secret: Secret parameter value to pass in the API call’s request body.
Client ID: JavaScript expression used to compute the application (client) ID for the Azure application. Can be a constant.
Scope: The OAuth scope to the appropriate endpoint URL for your Azure environment. This ensures that your OAuth tokens are valid and that your data is correctly ingested into Microsoft Sentinel. This setting should match the specific endpoint for your Azure environment:
- Azure Public Cloud (default):
https://monitor.azure.com/.default - Azure US Government Cloud:
https://monitor.azure.us/.default - Microsoft Azure operated by 21Vianet:
https://monitor.azure.cn/.default
Persistent Queue Settings
This tab is displayed when the Backpressure behavior is set to Persistent Queue.
On Cribl-managed Cribl.Cloud Workers (with an Enterprise plan), this tab exposes only the destructive Clear Persistent Queue button (described below in 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 Edge will block outbound data. To configure the queue size, compression, queue-full fallback behavior, and other options below, use a hybrid Group.
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 is allowed to consume on each Worker Process. Once this limit is reached, this Destination will stop queueing data and apply the Queue‑full behavior. Required, and defaults to 5 GB. Accepts positive numbers with units of KB, MB, GB, etc. Can be set as high as 1 TB, unless you’ve configured a different Max PQ size per Worker Process in Fleet Settings.
Queue file path: The location for the persistent queue files. Defaults to $CRIBL_HOME/state/queues. To this value, Cribl Edge will append /<worker‑id>/<output‑id>.
Compression: Codec to use to compress the persisted data, once a file is closed. Defaults to None; Gzip is also available.
Queue-full behavior: Whether to block or drop events when the queue is exerting backpressure (because disk is low or at full capacity). Block is the same behavior as non-PQ blocking, corresponding to the Block option on the Backpressure behavior drop-down. Drop new data throws away incoming data, while leaving the contents of the PQ unchanged.
Strict ordering: The default Yes position enables FIFO (first in, first out) event forwarding. When receivers recover, Cribl Edge will send earlier queued events before forwarding newly arrived events. To instead prioritize new events before draining the queue, toggle this off. Doing so will expose this additional control:
- Drain rate limit (EPS): Optionally, set a throttling rate (in events per second) on writing from the queue to receivers. (The default
0value disables throttling.) Throttling the queue’s drain rate can boost the throughput of new/active connections, by reserving more resources for them. You can further optimize Workers’ startup connections and CPU load at Fleet Settings > Worker Processes.
Processing Settings
Post‑Processing
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
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:
| Status Code | Action |
|---|---|
Any in the 1xx, 3xx, or 4xx series | Drop the request |
Any in the 5xx series | Retry the request |
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)or503 (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 is180,000(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 is180,000(180 seconds, or 3 minutes).
Advanced Settings
Validate server certs: Reject certificates that are not authorized by a trusted CA (for example, the system’s CA). Toggle this to No if you want Cribl Edge to accept such certificates. 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.
Compress: By default, Cribl Edge enables gzip-compress to compress the payload body before sending. Toggle this off if you want Cribl Edge not to gzip-compress the payload body.
Keep alive: By default, Cribl Edge sends Keep-Alive headers to the remote server and preserves the connection from the client side up to a maximum of 120 seconds. Toggle this off if you want Cribl Edge to close the connection immediately after sending a request.
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 1000 KB, the maximum allowed size of API call. Be aware that high values can cause high memory usage per Worker Node, especially if a dynamically constructed URL (see Internal Fields) causes this Destination to send events to more than one URL. 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.
Buffer memory limit (KB): Total amount of memory used to buffer outgoing requests waiting to be sent. If left blank, defaults to 5 times the max body size (if set). If 0, no limit is enforced. This provides granular control over the memory allocated for buffering outgoing batched requests. Increasing the limit allows batches to grow larger before being flushed, improving efficiency for data with high cardinality (a large number of unique batches). Finding the optimal balance between efficient data transfer and memory usage involves adjusting both the Buffer memory limit and Max Body Size settings.
Max events per request: Maximum number of events to include in the request body. The 0 default allows unlimited events.
Flush period (sec): 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 to all events as additional HTTP headers. Values will be sent encrypted. You can also add headers dynamically on a per-event basis in the __headers field. See Internal Fields below.
Failed request logging mode: Use this drop-down to determine which data should be logged when a request fails. Select among None (the default), Payload, or Payload + Headers. With this last option, Cribl Edge will redact all headers, except non-sensitive headers that you declare below in Safe headers.
Safe headers: Add headers to declare them as safe to log in plaintext. (Sensitive headers such as authorization will always be redacted, even if listed here.) Use a tab or hard return to separate header names.
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.
Internal Fields
Cribl Edge uses a set of internal fields to assist in forwarding data to a Destination.
Fields for this Destination:
__criblMetrics__url__headers
If an event contains the internal field __criblMetrics, Cribl Edge will send it to the HTTP endpoint as a metric event. Otherwise, Cribl Edge will send it as a log event.
If an event contains the internal field __url, that field’s value will override the General Settings > URL value. This way, you can determine the endpoint URL dynamically.
For example, you could create a Pipeline containing an Eval Function that adds the __url field, and connect that Pipeline to your Microsoft Sentinel Destination. Configure the Eval Function to set __url’s value to a URL that varies depending on a global variable, or on some property of the event, or on some other dynamically-generated value that meets your needs.
If an event contains the internal field __headers, that field’s value will be a JSON object containing Name-value pairs, each of which defines a header. By creating Pipelines that set the value of __headers according to conditions that you specify, you can add headers dynamically.
For example, you could create a Pipeline containing Eval Functions that add the __headers field, and connect that Pipeline to your Microsoft Sentinel Destination. Configure the Eval Functions to set __headers values to Name-value pairs that vary depending on some properties of the event, or on dynamically-generated values that meet your needs.
Here’s an overview of how to add headers:
- To add “dynamic” (a.k.a. “custom”) headers to some events but not others, use the
__headersfield. - To define headers to add to all events, use Advanced Settings > Extra HTTP Headers.
- An event can include headers added by both methods. So if you use
__headersto add{ "api‑key": "foo" }and Extra HTTP Headers to add{ "goat": "Kid A" }, you’ll get both headers. - Headers added via the
__headersfield take precedence. So if you use__headersto add{ "api‑key": "foo" }and Extra HTTP Headers to add{ "api‑key": "bar" }, you’ll get only one header, and that will be{ "api‑key": "foo" }.
Notes on HTTP-Based Outputs
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, it will throw away the connection and attempt a new one. 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), Cribl Edge will establish a new connection for the next request.
When resolving the Destination’s hostname, 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 among destination cluster nodes.
Troubleshooting
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.