Spring Boot Admin & Monitoring Microservices [Java Spring Boot Mastery Series – Part 17]

As your application grows into a distributed system (microservices), it becomes essential to monitor the health, performance, and status of each service. Spring Boot Admin makes this easy.

✅ What is Spring Boot Admin?

Spring Boot Admin is an open-source community project to manage and monitor Spring Boot applications via a web dashboard.

It provides:

• Health status (UP, DOWN)
• JVM metrics (memory, threads)
• Environment & configuration
• HTTP traces
• Loggers and levels
• Live logging configuration

🧱 Architecture Overview

• Spring Boot Admin Server: A web UI to monitor services.
• Spring Boot Admin Client: Each monitored app includes the client dependency to register itself with the server.

🛠️ 1. Setup Spring Boot Admin Server

🔹 Add Dependencies (admin-server pom.xml)

<dependency>
  <groupId>de.codecentric</groupId>
  <artifactId>spring-boot-admin-starter-server</artifactId>
  <version>3.2.3</version> <!-- Match your Spring Boot version -->
</dependency>
<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-actuator</artifactId>
</dependency>

🔹 Enable Admin Server

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

🔹 Configuration (application.yml)

server:
  port: 9090

spring:
  application:
    name: admin-server

management:
  endpoints:
    web:
      exposure:
        include: '*'

🧩 2. Setup Client (Monitored Service)

🔹 Add Dependencies (client pom.xml)

<dependency>
  <groupId>de.codecentric</groupId>
  <artifactId>spring-boot-admin-starter-client</artifactId>
  <version>3.2.3</version>
</dependency>
<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-actuator</artifactId>
</dependency>

🔹 Configuration (application.yml)

spring:
  application:
    name: my-service

  boot:
    admin:
      client:
        url: http://localhost:9090 # Admin server URL

management:
  endpoints:
    web:
      exposure:
        include: '*'
  endpoint:
    health:
      show-details: always

💻 3. Run and Monitor

1. Start the Admin Server (localhost:9090)
2. Start one or more clients (services with actuator + admin-client)
3. You’ll see them automatically appear in the dashboard 🖥️

🔎 Features in Admin Dashboard

Feature	Description
Health	Shows health status of services
Metrics	JVM metrics, CPU, memory, threads
Environment	View all environment variables
Beans	List of all beans loaded by Spring
Loggers	Change log levels dynamically
Threads	Thread dumps
HTTP Trace	Last few HTTP requests and responses

🔐 4. Securing the Admin Server

spring:
  security:
    user:
      name: admin
      password: secret

On the client side:

spring:
  boot:
    admin:
      client:
        username: admin
        password: secret

🧪 Testing Tips

• Simulate service failure → Admin shows DOWN
• Change log level from the UI (DEBUG, INFO, ERROR)

🧰 Optional: Add Notifications (Slack, Email, Teams)

Spring Boot Admin supports notifications when a service goes down or changes state.

Add this config:

spring.boot.admin.notify.slack.enabled: true
spring.boot.admin.notify.slack.webhook-url: https://hooks.slack.com/services/...

🧵 Spring Boot Admin vs Actuator UI

Feature	Actuator JSON API	Spring Boot Admin UI
UI	❌	✅
Multiservice support	❌	✅
Dynamic log levels	❌	✅
Thread dumps	Partial	✅
Notification Support	❌	✅

📦 Summary

Spring Boot Admin provides a central monitoring dashboard with little effort. Ideal for microservices and production monitoring. Combine it with:

• Prometheus/Grafana → Metrics
• ELK/EFK Stack → Logs
• Zipkin/Jaeger → Tracing

➡️ Next Up: Part 18 – Distributed Tracing with Sleuth and Zipkin