How to Setup Alerting in the Elastic Stack

In this article we will learn about Alerting in the Elastic Stack. Alerting in the Elastic Stack empowers users to monitor real-time data, detect anomalies, and trigger automated actions when specific conditions are met. Integrated into Kibana’s Stack Management, this feature is essential for observability, security, and operational excellence. Whether you’re overseeing infrastructure, applications, or logs, Elastic Alerting ensures you stay informed and can act quickly.

What is Alerting in the Elastic Stack?

Alerting allows you to monitor your data and receive notifications when certain conditions are met.
It is a part of Kibana, integrated into Stack Management. Its Use cases:

• Infrastructure monitoring
• Security alerts
• Application performance issues
• Log anomaly detection

Elastic Stack Alerting Workflow

Key Concepts

1. Rule (Alert Rule)
   • Definition:
     An Alert Rule is the definition of what you want to monitor. It continuously evaluates data in Elasticsearch and determines if specific conditions are met.
   • Example:
     • You want to be alerted when the number of error logs exceeds 50 in the last 5 minutes.
     • Rule Type: Log threshold rule
     • Criteria: Count of logs where log.level = “error” is greater than 50 over 5 minutes
   • Other Examples:
     • CPU usage > 80% (metrics index)
     • HTTP response time > 2 seconds (APM data)
2. Trigger
   • Definition:
     A Trigger is the condition that, when met, causes the alert rule to fire.
     The trigger is part of the alert rule and defines exactly when an action should be taken.
   • Example:
     • In the rule to monitor error logs, the trigger could be:
     • “If log error count > 50 within last 5 minutes” → then fire the alert
   • You can also define thresholds like:
     • Average response time > 2000ms
     • Count of failed login attempts > 5 from the same IP
3. Action
   • Definition:
     An Action is what happens when a trigger condition is met.
     It notifies the relevant person or system.
   • Examples:
     • Send an email to the support team
     • Send a message to a Slack channel
     • Call a Webhook to trigger another system (e.g., auto-scale server)
     • Create an issue in Jira
   • Example Template:
     • Subject: High Error Rate Detected
     • Message:
       We detected more than 50 error logs in the last 5 minutes.
       Timestamp: {{context.timestamp}}
       Host: {{context.host.name}}
4. Connector
   • Definition:
     A Connector is the integration configuration for an external service where actions are sent. Think of it as a saved endpoint with credentials and settings. You can reuse it across multiple alert rules.
   • Types of Connectors:
     • Email: SMTP settings for sending emails
     • Slack: Webhook URL for sending Slack messages
     • Webhook: Any HTTP endpoint
     • Index: Store alert data back into Elasticsearch
     • Jira, ServiceNow, Teams, PagerDuty, etc.
   • Example (Email Connector):
     • SMTP Host: smtp.gmail.com
     • Port: 587
     • Username: [email protected]
     • Password: [App-specific password]
     • Sender: [email protected]
     • Once created, this connector can be used in multiple alert rules.

Types of Alert Rules

Elastic Stack provides a rich variety of built-in alert types. These are pre-defined rules tailored for common observability and security use cases, spanning APM, logs, metrics, uptime, and machine learning.

Below is a table outlining the major alert rule types, their use cases, and license requirements:

Category	Rule Type	Description	License
APM and  User Experience	APM Anomaly	Alert on anomalies in  latency, throughput, or failed transaction rate	Free
	Error count threshold	Alert when error count in a service exceeds a threshold	Free
	Failed transaction rate threshold	Alert when  transaction error rate exceeds threshold	Free
	Latency threshold	Alert when  transaction latency  exceeds threshold	Free
Synthetics and Uptime	Synthetics monitor  status	Alert when Synthetics monitor is down	Free
	Synthetics TLS  certificate	Alert when a TLS  certificate is about to expire	Free
	Uptime monitor status	Alert when uptime  status is down or  availability breached	Free
	Uptime TLS	Alert when a TLS  certificate in Uptime is expiring	Free
	Uptime Duration  Anomaly	Alert on anomalous  response duration in  Uptime monitors	❗ Platinum only
Infrastructure	Inventory	Alert when monitored infrastructure  (e.g., hosts) exceed  CPU/memory/disk  thresholds	Free
	Metric threshold	Alert when aggregated metrics exceed a  defined value	Free
Logs	Log threshold	Alert when log count  or aggregation meets/exceeds threshold	Free
Stack Alerts	Elasticsearch query	Alert when an  Elasticsearch query  returns matching  results	Free
Observability	Custom threshold	Alert across any  Observability data  type using custom  thresholds	Free
Machine Learning	Anomaly detection	Alert based on  anomaly detection job results	❗ Platinum only
SLOs	SLO burn rate	Alert when your SLO burn rate is too high  over a defined time  window	❗ Platinum only

These alert types allow teams to address infrastructure health, application performance, and security threats in a proactive way.

Connector Types: Free vs. Paid

Elastic Stack provides multiple connectors to deliver alerts. Some are available for free, while others require a Gold, Platinum, or Enterprise license, depending on the service’s criticality and integration complexity.

Here’s a breakdown of connector types and the license needed:

Elastic Cloud vs. Self-Managed Licensing

Elastic Stack can be deployed via Elastic Cloud (fully managed by Elastic) or Self-Managed (on your infrastructure). Each has differences in licensing, scalability, and feature availability.

Here’s a quick comparison:

Feature	Elastic Cloud	Self-Managed (On-Prem)
Licensing Model	Subscription-based, managed by Elastic	Free (Basic), or paid licenses  (Gold, Platinum, Enterprise)
License Activation	Automatically activated  through Elastic account	Requires manual upload of  license file
Scaling & Maintenance	Handled by Elastic (auto-scaling, upgrades, snapshots)	You manage hardware, scaling, backups, and upgrades
Connectors Availability	Full access based on plan tier	Limited or license-dependent
Trial Access	30 – day trial available for all features.	Requires enabling trial license manually
Elastic Cloud Features	Includes exclusive features  (e.g., autoscaling, Elastic AI)	Some advanced features may be unavailable
Support	Comes with SLA-backed Support (based on plan)	Requires separate support subscription

Some alert connectors and rule types (like ML-based alerts, SLO Burn Rate, or AI integrations) are only available on Platinum or Enterprise tiers, whether on Elastic Cloud or self-managed.

Setting Up an Alert in Elastic Stack

Kibana provides an intuitive UI for creating and managing alerts. Here’s how you can set up a new alert from start to finish:

1. Navigate to Kibana: Go to “Stack Management” -> “Rules and Connectors”.
2. Create a New Rule: Choose the appropriate rule type (e.g., “Index threshold”, “Elasticsearch query”).
3. Define Conditions: Specify the query, aggregation, or threshold that triggers the alert.
4. Set Schedule: Determine how frequently the rule should check for the condition.
5. Configure Actions:
   • Add an action.
   • Select a connector (e.g., Email, Slack, Webhook).
   • Configure the message content using variables (e.g., {{context.timestamp}}, {{context.host.name}}).
6. Save the Rule: The rule will start running based on its schedule.

Best Practices for Alerting in Elastic Stack

To maximize effectiveness and reduce alert fatigue, consider the following tips:

1. Be Specific with Alert Rules
   • Define clear thresholds or queries to reduce noise.
   • Use filters to target exact data segments (e.g., service name, host).
2. Avoid Alert Fatigue
   • Tune thresholds carefully to avoid excessive alerting.
   • Use deduplication and throttling options.
3. Use Action Groups
   • Group similar alert actions (e.g., notify via Slack and PagerDuty) to simplify management.
4. Use the Right Connector
   • For mission-critical alerts, prefer high-reliability channels like PagerDuty or Opsgenie.
   • For logs/metrics debugging, use Index or Server Log.
5. Combine Alerts with Dashboards
   • Link alerts to Kibana dashboards for quick context and visual analysis.

These best practices help teams stay focused and act efficiently without being overwhelmed by irrelevant alerts.

Common Alerting Use Cases

Alerting in the Elastic Stack supports a wide variety of operational and business needs. Popular use cases include:

• Monitoring system infrastructure (CPU, memory, disk)
• Alerting on security threats (e.g., brute-force login attempts)
• Application performance degradation (e.g., high latency)
• Unusual log patterns or spikes (log anomalies)
• Service Level Objectives (SLO) violations
• Downtime or availability issues (uptime monitors)

Conclusion:

Elastic Stack Alerting brings together the powerful capabilities of Elasticsearch, Kibana, and external systems to ensure you’re never caught off guard by critical issues. Whether hosted on Elastic Cloud or self-managed, with the right rule definitions and connectors in place, you can automate incident response, minimize downtime, and boost operational awareness.

Related Articles:

Elastic Stack Tutorial for Beginners:ELK (Elasticsearch, Logstash, Kibana, Beats)

Reference:

Alerting in Elastic Stack official page