Set up the Server

Running Behind a Front-end Proxy Server

In case the Spring Boot Admin server is running behind a reverse proxy, it may be requried to configure the public url where the server is reachable via (spring.boot.admin.ui.public-url). In addition when the reverse proxy terminates the https connection, it may be necessary to configure server.forward-headers-strategy=native (also see Spring Boot Reference Guide).

Spring Cloud Discovery

The Spring Boot Admin Server can use Spring Clouds DiscoveryClient to discover applications. The advantage is that the clients don’t have to include the spring-boot-admin-starter-client. You just have to add a DiscoveryClient implementation to your admin server - everything else is done by AutoConfiguration.

Static Configuration using SimpleDiscoveryClient

Spring Cloud provides a SimpleDiscoveryClient. It allows you to specify client applications via static configuration:

pom.xml
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter</artifactId>
</dependency>

application.yml
spring:
  cloud:
    discovery:
      client:
        simple:
          instances:
            test:
              - uri: http://instance1.intern:8080
                metadata:
                  management.context-path: /actuator
              - uri: http://instance2.intern:8080
                metadata:
                  management.context-path: /actuator

Other DiscoveryClients

Spring Boot Admin supports all other implementations of Spring Cloud’s DiscoveryClient (Eureka, Zookeeper, Consul, Kubernetes, …). You need to add it to the Spring Boot Admin Server and configure it properly. An example setup using Eureka is shown above.

Converting ServiceInstances

The information from the service registry are converted by the ServiceInstanceConverter. Spring Boot Admin ships with a default and Eureka converter implementation. The correct one is selected by AutoConfiguration.

tip

You can modify how the information from the registry is used to register the application by using SBA Server configuration options and instance metadata. The values from the metadata takes precedence over the server config. If the plenty of options don’t fit your needs you can provide your own ServiceInstanceConverter.

tip

When using Eureka, the healthCheckUrl known to Eureka is used for health-checking, which can be set on your client using eureka.instance.healthCheckUrl.

Instance metadata options

Key	Value	Default value
user.nameuser.password	Credentials being used to access the endpoints.
management.scheme	The scheme is substituted in the service URL and will be used for accessing the actuator endpoints.
management.address	The address is substituted in the service URL and will be used for accessing the actuator endpoints.
management.port	The port is substituted in the service URL and will be used for accessing the actuator endpoints.
management.context-path	The path is appended to the service URL and will be used for accessing the actuator endpoints.	${spring.boot.admin.discovery.converter.management-context-path}
health.path	The path is appended to the service URL and will be used for the health-checking. Ignored by the EurekaServiceInstanceConverter.	${spring.boot.admin.discovery.converter.health-endpoint}
group	The group is used to group services in the UI by the group name instead of application name.

Discovery configuration options

Property name	Description	Default value
spring.boot.admin.discovery.enabled	Enables the DiscoveryClient-support for the admin server.	true
spring.boot.admin.discovery.converter.management-context-path	Will be appended to the service-url of the discovered service when the management-url is converted by the DefaultServiceInstanceConverter.	/actuator
spring.boot.admin.discovery.converter.health-endpoint-path	Will be appended to the management-url of the discovered service when the health-url is converted by the DefaultServiceInstanceConverter.	"health"
spring.boot.admin.discovery.ignored-services	This services will be ignored when using discovery and not registered as application. Supports simple patterns (e.g. "foo", "bar", "foobar"). The check is case-insensitive.
spring.boot.admin.discovery.services	This services will be included when using discovery and registered as application. Supports simple patterns (e.g. "foo", "bar", "foobar").	"*"
spring.boot.admin.discovery.ignored-instances-metadata	Instances of services will be ignored if they contain at least one metadata item that matches this list. (e.g. "discoverable=false")
spring.boot.admin.discovery.instances-metadata	Instances of services will be included if they contain at least one metadata item that matches this list. (e.g. "discoverable=true")

CloudFoundry

If you are deploying your applications to CloudFoundry then vcap.application.application_id and vcap.application.instance_index must be added to the metadata for proper registration of applications with Spring Boot Admin Server. Here is a sample configuration for Eureka:

application.yml
eureka:
  instance:
    hostname: ${vcap.application.uris[0]}
    nonSecurePort: 80
    metadata-map:
      applicationId: ${vcap.application.application_id}
      instanceId: ${vcap.application.instance_index}

Clustering

Spring Boot Admin Server supports cluster replication via Hazelcast. It is automatically enabled when a HazelcastConfig- or HazelcastInstance-Bean is present. You can also configure the Hazelcast instance to be persistent, to keep the status over restarts. Also have a look at the Spring Boot support for Hazelcast.

Add Hazelcast to your dependencies:

pom.xml
<dependency>  
    <groupId>com.hazelcast</groupId>  
    <artifactId>hazelcast</artifactId>  
</dependency>  

Instantiate a HazelcastConfig:

HazelcastConfig.java
@Bean  
public Config hazelcastConfig() {  
    // This map is used to store the events.  
    // It should be configured to reliably hold all the data,  
    // Spring Boot Admin will compact the events, if there are too many  
    MapConfig eventStoreMap = new MapConfig(DEFAULT_NAME_EVENT_STORE_MAP).setInMemoryFormat(InMemoryFormat.OBJECT)  
        .setBackupCount(1)  
        .setMergePolicyConfig(new MergePolicyConfig(PutIfAbsentMergePolicy.class.getName(), 100));  
    // This map is used to deduplicate the notifications.  
    // If data in this map gets lost it should not be a big issue as it will atmost  
    // lead to  
    // the same notification to be sent by multiple instances  
    MapConfig sentNotificationsMap = new MapConfig(DEFAULT_NAME_SENT_NOTIFICATIONS_MAP)  
        .setInMemoryFormat(InMemoryFormat.OBJECT)  
        .setBackupCount(1)  
        .setEvictionConfig(  
                new EvictionConfig().setEvictionPolicy(EvictionPolicy.LRU).setMaxSizePolicy(MaxSizePolicy.PER_NODE))  
        .setMergePolicyConfig(new MergePolicyConfig(PutIfAbsentMergePolicy.class.getName(), 100));  
    Config config = new Config();  
    config.addMapConfig(eventStoreMap);  
    config.addMapConfig(sentNotificationsMap);  
    config.setProperty("hazelcast.jmx", "true");  
    // WARNING: This setups a local cluster, you change it to fit your needs.  
    config.getNetworkConfig().getJoin().getMulticastConfig().setEnabled(false);  
    TcpIpConfig tcpIpConfig = config.getNetworkConfig().getJoin().getTcpIpConfig();  
    tcpIpConfig.setEnabled(true);  
    tcpIpConfig.setMembers(singletonList("127.0.0.1"));  
    return config;  
}  

Hazelcast configuration options

Property name	Description	Default value
spring.boot.admin.hazelcast.enabled	Enables the Hazelcast support	true
spring.boot.admin.hazelcast.event-store	Name of the Hazelcast-map to store the events	"spring-boot-admin-event-store"
spring.boot.admin.hazelcast.sent-notifications	Name of the Hazelcast-map used to deduplicate the notifications.	"spring-boot-admin-sent-notifications"

Running Behind a Front-end Proxy Server​

Spring Cloud Discovery​

Static Configuration using SimpleDiscoveryClient​

Other DiscoveryClients​

Converting ServiceInstances​

CloudFoundry​

Clustering​