Alertingedit

Alerting allows you to define rules to detect complex conditions within different Kibana apps and trigger actions when those conditions are met. Alerting is integrated with Observability, Security, Maps and Machine Learning, can be centrally managed from the Management UI, and provides a set of built-in connectors and rules (known as stack rules) for you to use.

Rules and Connectors UI

To make sure you can access alerting and actions, see the setup and pre-requisites section.

Concepts and terminologyedit

Alerting works by running checks on a schedule to detect conditions defined by a rule. When a condition is met, the rule tracks it as an alert and responds by triggering one or more actions. Actions typically involve interaction with Kibana services or third party integrations. Connectors allow actions to talk to these services and integrations. This section describes all of these elements and how they operate together.

What is a rule?edit

A rule specifies a background task that runs on the Kibana server to check for specific conditions. It consists of three main parts:

  • Conditions: what needs to be detected?
  • Schedule: when/how often should detection checks run?
  • Actions: what happens when a condition is detected?

For example, when monitoring a set of servers, a rule might check for average CPU usage > 0.9 on each server for the last two minutes (condition), checked every minute (schedule), sending a warning email message via SMTP with subject CPU on {{server}} is high (action).

Three components of a rule

The following sections describe each part of the rule in more detail.

Conditionsedit

Under the hood, Kibana rules detect conditions by running a javascript function on the Kibana server, which gives it the flexibility to support a wide range of conditions, anything from the results of a simple Elasticsearch query to heavy computations involving data from multiple sources or external systems.

These conditions are packaged and exposed as rule types. A rule type hides the underlying details of the condition, and exposes a set of parameters to control the details of the conditions to detect.

For example, an index threshold rule type lets you specify the index to query, an aggregation field, and a time window, but the details of the underlying Elasticsearch query are hidden.

See Stack rule types and Domain-specific rules for the types of rules provided by Kibana and how they express their conditions.

Scheduleedit

Rule schedules are defined as an interval between subsequent checks, and can range from a few seconds to months.

The intervals of rule checks in Kibana are approximate. The timing of their execution is affected by factors such as the frequency at which tasks are claimed and the task load on the system. See Alerting production considerations for more information.

Actionsedit

Actions are invocations of connectors, which allow interaction with Kibana services or integrations with third-party systems. Actions run as background tasks on the Kibana server when rule conditions are met.

When defining actions in a rule, you specify:

  • the connector type: the type of service or integration to use
  • the connection for that type by referencing a connector
  • a mapping of rule values to properties exposed for that type of action

The result is a template: all the parameters needed to invoke a service are supplied except for specific values that are only known at the time the rule condition is detected.

In the server monitoring example, the email connector type is used, and server is mapped to the body of the email, using the template string CPU on {{server}} is high.

When the rule detects the condition, it creates an alert containing the details of the condition, renders the template with these details such as server name, and executes the action on the Kibana server by invoking the email connector type.

Actions are like templates that are rendered when an alert detects a condition

See Connectors for details on the types of connectors provided by Kibana.

Alertsedit

When checking for a condition, a rule might identify multiple occurrences of the condition. Kibana tracks each of these alerts separately and takes an action per alert.

Using the server monitoring example, each server with average CPU > 0.9 is tracked as an alert. This means a separate email is sent for each server that exceeds the threshold.

Kibana tracks each detected condition as an alert and takes action on each alert

Suppressing duplicate notificationsedit

Since actions are executed per alert, a rule can end up generating a large number of actions. Take the following example where a rule is monitoring three servers every minute for CPU usage > 0.9:

  • Minute 1: server X123 > 0.9. One email is sent for server X123.
  • Minute 2: X123 and Y456 > 0.9. Two emails are sent, one for X123 and one for Y456.
  • Minute 3: X123, Y456, Z789 > 0.9. Three emails are sent, one for each of X123, Y456, Z789.

In the above example, three emails are sent for server X123 in the span of 3 minutes for the same rule. Often it’s desirable to suppress frequent re-notification. Operations like muting and throttling can be applied at the alert level. If we set the rule re-notify interval to 5 minutes, we reduce noise by only getting emails for new servers that exceed the threshold:

  • Minute 1: server X123 > 0.9. One email is sent for server X123.
  • Minute 2: X123 and Y456 > 0.9. One email is sent for Y456.
  • Minute 3: X123, Y456, Z789 > 0.9. One email is sent for Z789.

Connectorsedit

Actions often involve connecting with services inside Kibana or integrating with third-party systems. Rather than repeatedly entering connection information and credentials for each action, Kibana simplifies action setup using connectors.

Connectors provide a central place to store connection information for services and integrations. For example if four rules send email notifications via the same SMTP service, they can all reference the same SMTP connector. When the SMTP settings change, you can update them once in the connector, instead of having to update four rules.

Connectors provide a central place to store service connection settings

Summaryedit

A rule consists of conditions, actions, and a schedule. When conditions are met, alerts are created that render actions and invoke them. To make action setup and update easier, actions use connectors that centralize the information used to connect with Kibana services and third-party integrations. The following example ties these concepts together:

Rules
  1. Anytime a rule's conditions are met, an alert is created. This example checks for servers with average CPU > 0.9. Three servers meet the condition, so three alerts are created.
  2. Alerts create actions as long as they are not muted or throttled. When actions are created, the template that was setup in the rule is filled with actual values. In this example, three actions are created, and the template string {{server}} is replaced with the server name for each alert.
  3. Kibana invokes the actions, sending them to a third party integration like an email service.
  4. If the third party integration has connection parameters or credentials, Kibana will fetch these from the connector referenced in the action.

Differences from Watcheredit

Kibana alerting and Elasticsearch alerting are both used to detect conditions and can trigger actions in response, but they are completely independent alerting systems.

This section will clarify some of the important differences in the function and intent of the two systems.

Functionally, Kibana alerting differs in that:

  • Scheduled checks are run on Kibana instead of Elasticsearch
  • Kibana rules hide the details of detecting conditions through rule types, whereas watches provide low-level control over inputs, conditions, and transformations.
  • Kibana rules track and persist the state of each detected condition through alerts. This makes it possible to mute and throttle individual alerts, and detect changes in state such as resolution.
  • Actions are linked to alerts in Kibana alerting. Actions are fired for each occurrence of a detected condition, rather than for the entire rule.

At a higher level, Kibana alerting allows rich integrations across use cases like APM, Metrics, Security, and Uptime. Pre-packaged rule types simplify setup and hide the details of complex, domain-specific detections, while providing a consistent interface across Kibana.

Setup and prerequisitesedit

If you are using an on-premises Elastic Stack deployment:

If you are using an on-premises Elastic Stack deployment with security:

Production considerations and scaling guidanceedit

When relying on alerting and actions as mission critical services, make sure you follow the Alerting production considerations.

See Scaling Guidance for more information on the scalability of Kibana alerting.

Securityedit

To access alerting in a space, a user must have access to one of the following features:

See feature privileges for more information on configuring roles that provide access to these features. Also note that a user will need read privileges for the Actions and Connectors feature to attach actions to a rule or to edit a rule that has an action attached to it.

Space isolationedit

Rules and connectors are isolated to the Kibana space in which they were created. A rule or connector created in one space will not be visible in another.

Authorizationedit

Rules, including all background detection and the actions they generate are authorized using an API key associated with the last user to edit the rule. Upon creating or modifying a rule, an API key is generated for that user, capturing a snapshot of their privileges at that moment in time. The API key is then used to run all background tasks associated with the rule including detection checks and executing actions.

If a rule requires certain privileges to run, such as index privileges, keep in mind that if a user without those privileges updates the rule, the rule will no longer function.

Restricting actionsedit

For security reasons you may wish to limit the extent to which Kibana can connect to external services. Action settings allows you to disable certain Connectors and allowlist the hostnames that Kibana can connect with.