Service Discovery Integration

Spring Boot Admin integrates seamlessly with Spring Cloud Discovery services, allowing automatic registration without the Spring Boot Admin Client library.

Overview

When using service discovery, the Admin Server discovers applications automatically through the discovery client. This eliminates the need for:

Spring Boot Admin Client dependency
Explicit Admin Server URL configuration
Manual registration code

Supported Discovery Services

Eureka (Netflix)
Consul (HashiCorp)
Zookeeper (Apache)
Kubernetes (via Spring Cloud Kubernetes)

Eureka Integration

Server Setup

Add Eureka Client to your Admin Server:

xml

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>

Enable discovery in your Admin Server:

java

import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import de.codecentric.boot.admin.server.config.EnableAdminServer;

@EnableDiscoveryClient
@EnableAdminServer
@SpringBootApplication
public class SpringBootAdminApplication {
    static void main(String[] args) {
        SpringApplication.run(SpringBootAdminApplication.class, args);
    }
}

Configure Eureka connection:

yaml

spring:
  application:
    name: spring-boot-admin-server

eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:8761/eureka/
    registryFetchIntervalSeconds: 5
  instance:
    leaseRenewalIntervalInSeconds: 10
    health-check-url-path: /actuator/health

management:
  endpoints:
    web:
      exposure:
        include: "*"
  endpoint:
    health:
      show-details: ALWAYS

Client Setup

Add Eureka Client to your application (no Admin Client needed):

xml

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>

Enable discovery:

java

@EnableDiscoveryClient
@SpringBootApplication
public class MyApplication {
    public static void main(String[] args) {
        SpringApplication.run(MyApplication.class, args);
    }
}

Configure Eureka and expose endpoints:

yaml

spring:
  application:
    name: my-application

eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:8761/eureka/
  instance:
    leaseRenewalIntervalInSeconds: 10
    health-check-url-path: /actuator/health
    metadata-map:
      startup: ${random.int}  # Triggers info update on restart
      user.name: ${spring.security.user.name}  # For secured actuators
      user.password: ${spring.security.user.password}

management:
  endpoints:
    web:
      exposure:
        include: "*"
  endpoint:
    health:
      show-details: ALWAYS

Eureka Metadata

Add custom metadata through Eureka:

yaml

eureka:
  instance:
    metadata-map:
      startup: ${random.int}
      tags.environment: production
      tags.region: us-east-1
      team: platform
      version: ${spring.application.version}

Consul Integration

Server Setup

xml

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-consul-discovery</artifactId>
</dependency>

java

@EnableDiscoveryClient
@EnableAdminServer
@SpringBootApplication
public class SpringBootAdminApplication {
    static void main(String[] args) {
        SpringApplication.run(SpringBootAdminApplication.class, args);
    }
}

yaml

spring:
  application:
    name: spring-boot-admin-server
  cloud:
    consul:
      host: localhost
      port: 8500
      discovery:
        prefer-ip-address: true
        health-check-interval: 10s

Client Setup

xml

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-consul-discovery</artifactId>
</dependency>

yaml

spring:
  application:
    name: my-application
  cloud:
    consul:
      host: localhost
      port: 8500
      discovery:
        metadata:
          user-name: ${spring.security.user.name}  # Note: dashes not dots!
          user-password: ${spring.security.user.password}
          environment: production
          management-context-path: ${management.server.base-path:/actuator}

management:
  endpoints:
    web:
      exposure:
        include: "*"

:::warning Consul does not allow dots (.) in metadata keys. Use dashes (-) or underscores (_) instead:

✅ user-name or user_name
❌ user.name :::

Zookeeper Integration

Server Setup

xml

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-zookeeper-discovery</artifactId>
</dependency>

yaml

spring:
  application:
    name: spring-boot-admin-server
  cloud:
    zookeeper:
      connect-string: localhost:2181
      discovery:
        enabled: true

Client Setup

xml

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-zookeeper-discovery</artifactId>
</dependency>

yaml

spring:
  application:
    name: my-application
  cloud:
    zookeeper:
      connect-string: localhost:2181
      discovery:
        metadata:
          user.name: ${spring.security.user.name}
          user.password: ${spring.security.user.password}
          management.context-path: /actuator

Filtering Discovered Services

By default, the Admin Server monitors all discovered services. You can filter services using the InstanceFilter interface.

Configuration-Based Filtering

yaml

spring:
  boot:
    admin:
      discovery:
        ignored-services: consul,eureka,zookeeper  # Don't monitor discovery services

Custom InstanceFilter

java

import de.codecentric.boot.admin.server.domain.values.Registration;
import de.codecentric.boot.admin.server.services.InstanceFilter;
import org.springframework.stereotype.Component;

@Component
public class CustomInstanceFilter implements InstanceFilter {

    @Override
    public boolean test(Registration registration) {
        String name = registration.getName();

        // Ignore internal services
        if (name.startsWith("internal-")) {
            return false;
        }

        // Only monitor services with specific metadata
        String monitorable = registration.getMetadata().get("monitorable");
        if (!"true".equals(monitorable)) {
            return false;
        }

        return true;
    }
}

Instance Preference Strategy

When multiple instances of the same service exist, configure which instance URL to use:

yaml

spring:
  boot:
    admin:
      discovery:
        instance-prefer-ip: true  # Use IP instead of hostname

Management Context Path

If your management endpoints are on a different port or path:

yaml

management:
  server:
    port: 9090  # Management on different port
    base-path: /management

eureka:
  instance:
    metadata-map:
      management.port: 9090
      management.context-path: /management

Health Check Configuration

Configure health check paths for discovery:

yaml

eureka:
  instance:
    health-check-url-path: /actuator/health
    health-check-url: http://my-app.example.com/actuator/health
    status-page-url-path: /actuator/info
    home-page-url: /

Service URL vs Management URL

Discovery services may return different URLs for the service and management endpoints:

yaml

eureka:
  instance:
    metadata-map:
      management.context-path: /actuator  # Management endpoint path
      service-url: https://my-app.example.com  # Public service URL
      management-url: http://internal-app:8080/actuator  # Internal mgmt URL

Securing Discovered Services

Pass credentials through metadata:

yaml

eureka:
  instance:
    metadata-map:
      user.name: admin
      user.password: ${ACTUATOR_PASSWORD}

Or configure on the Admin Server:

yaml

spring:
  boot:
    admin:
      instance-auth:
        enabled: true
        default-user-name: admin
        default-password: ${DEFAULT_PASSWORD}
        service-map:
          my-application:
            user-name: app-admin
            user-password: ${APP_PASSWORD}

Advantages of Service Discovery

No Client Library Required: Applications don't need Spring Boot Admin Client
Automatic Discovery: New instances automatically appear
Centralized Configuration: Manage discovery in one place
Load Balancing: Discovery services handle load balancing
Health Checks: Built-in health check integration
Service Metadata: Rich metadata support

Disadvantages

Additional Infrastructure: Requires running discovery service
Network Complexity: Additional network hop
Discovery Lag: Slight delay in detecting new instances
Metadata Limitations: Some discovery services have metadata restrictions

Mixed Mode

You can use both service discovery and direct client registration simultaneously:

yaml

spring:
  boot:
    admin:
      client:
        url: http://localhost:8080  # Direct registration
        auto-registration: true

eureka:
  client:
    enabled: true  # Also register with Eureka

This provides redundancy if one registration method fails.

Troubleshooting

Application Not Discovered

Check Discovery Registration:

bash

# For Eureka
curl http://localhost:8761/eureka/apps

Verify Admin Server Discovery Client: Ensure @EnableDiscoveryClient is present
Check Network Connectivity: Admin Server must reach discovery service
Review Metadata: Ensure management URLs are correct

Incorrect Management URL

Set explicit management metadata:

yaml

eureka:
  instance:
    metadata-map:
      management.port: ${management.server.port}
      management.context-path: ${management.server.base-path}

Health Check Failures

Ensure health endpoint is accessible:

yaml

management:
  endpoint:
    health:
      show-details: ALWAYS
  endpoints:
    web:
      exposure:
        include: health,info

Best Practices

Use Metadata for Configuration: Leverage metadata for flexible configuration
Set Appropriate Intervals: Balance between freshness and load
Implement Filters: Don't monitor unnecessary services
Secure Metadata Transmission: Use secure discovery service connections
Monitor Discovery Health: Ensure discovery service is healthy
Document Metadata Schema: Maintain clear metadata conventions
Test Failover: Verify behavior when discovery service is down

Service Discovery Integration

Service Discovery Integration

Overview

Supported Discovery Services

Eureka Integration

Server Setup

Client Setup

Eureka Metadata

Consul Integration

Server Setup

Client Setup

Zookeeper Integration

Server Setup

Client Setup

Filtering Discovered Services

Configuration-Based Filtering

Custom InstanceFilter

Instance Preference Strategy

Management Context Path

Health Check Configuration

Service URL vs Management URL

Securing Discovered Services

Advantages of Service Discovery

Disadvantages

Mixed Mode

Troubleshooting

Application Not Discovered

Incorrect Management URL

Health Check Failures

Best Practices

See Also