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Today, I will talk to you about how to use eureka to achieve a registration center in springcloud. Many people may not know much about it. In order to make you understand better, the editor has summarized the following content for you. I hope you can get something according to this article.

Brief introduction

Spring Cloud is one of the mainstream frameworks for the development of micro-services. We all know that the most basic and core module in micro-service architecture is service registration and discovery.

In Spring Cloud, we can use its Eureka module to achieve service registration and discovery. Spring Cloud Eureka is secondary encapsulated based on Netflix Eureka, which is mainly responsible for completing the automatic registration and discovery of each micro-service instance.

Eureka contains two components: Eureka Server and Eureka Client

EurekaServer provides service registration services. After each node is started, it will register in EurekaServer, so that the information of all available service nodes will be stored in the service registry in EurekaServer, and the information of service nodes can be seen intuitively in the interface.

EurekaClient is a Java client that simplifies Eureka Server interaction and also has a built-in load balancer that uses the polling (round-robin) load algorithm. After the application starts, a heartbeat is sent to the Eureka Server (the default period is 30 seconds). If EurekaServer does not receive a heartbeat from a node in multiple heartbeat cycles, EurekaServer will remove the service node from the service registry (default is 90 seconds)

Build and deploy eureka server

1. If the single point deployment is idea, you can directly new project > > springinitializr > > cloud discovery.

Follow the steps to build a single point of eureka server

2. Cluster deployment generally consists of three or more nodes in the production environment, and each node in the cluster registers itself as a provider. The application.yml configuration is as follows

Server: port: 8761spring: application: name: eureka profiles: active: dev security: basic: enabled: false # enable authentication user: name: lipeng # define user name password: lipeng. # define password-spring: profiles: prd-1eureka: instance: hostname: register1 client: fetch-registry: true register-with-eureka: true serviceUrl: defaultZone: http://lipeng:lipeng.@200.200.0.166:8761/eureka/,http://lipeng:lipeng.@200.200.0.167:8761/eureka/, Http://lipeng:lipeng.@200.200.0.171:8761/eureka/ instance: prefer-ip-address: true ip-address: 200.200.0.166 server: # configuration Properties However, due to the Eureka self-protection mode and the long heartbeat cycle, We often encounter the problem that Eureka Server does not eliminate closed nodes enable-self-preservation: false eviction-interval-timer-in-ms: 5000---spring: profiles: prd-2eureka: instance: hostname: register2 client: fetch-registry: true register-with-eureka: true serviceUrl: defaultZone: http://lipeng:lipeng.@200.200.0.166:8761/eureka/,http://lipeng:lipeng.@200.200.0.167:8761/eureka/, Http://lipeng:lipeng.@200.200.0.171:8761/eureka/ instance: prefer-ip-address: true ip-address: 200.200.0.171 server: # configuration Properties However, due to the Eureka self-protection mode and the long heartbeat cycle, We often encounter the problem that Eureka Server does not eliminate closed nodes enable-self-preservation: false eviction-interval-timer-in-ms: 5000---spring: profiles: prd-3eureka: instance: hostname: register3 client: fetch-registry: true register-with-eureka: true serviceUrl: defaultZone: http://lipeng:lipeng.@200.200.0.166:8761/eureka/,http://lipeng:lipeng.@200.200.0.167:8761/eureka/, Http://lipeng:lipeng.@200.200.0.171:8761/eureka/ instance: prefer-ip-address: true ip-address: 200.200.0.167 server: # configuration Properties However, due to the self-protection mode of Eureka and the long heartbeat cycle, we often encounter the problem that Eureka Server does not eliminate the closed nodes enable-self-preservation: false eviction-interval-timer-in-ms: 5000

Add it to the startup command when deploying after packaging-- after spring.profile.active=prd-1/prd-2/prd-3 starts, it is as follows:

Only in this way can the deployment be considered successful, but not if the above two nodes are in unavailable-replicas.

Integration of eureka in K8s

Generally speaking, it is not recommended to use eureka in K8s, but sometimes it is best to fill in the domain name when deploying if necessary. Just set the variable

Eureka client

This is relatively simple. There are many examples of pom dependence on the Internet.

Org.springframework.cloud spring-cloud-starter-netflix-eureka-client

Add annotated yml configuration

Spring: profiles: deveureka: instance: prefer-ip-address: true lease-renewal-interval-in-seconds: 5 lease-expiration-duration-in-seconds: 20 hostname: ${spring.application.name} client: serviceUrl: defaultZone: http://lipeng:lipeng.@200.200.0.166:8761/eureka/,http://lipeng:lipeng.@200.200.0.167:8761/eureka/, Http://lipeng:lipeng.@200.200.0.171:8761/eureka/ registry-fetch-interval-seconds: 10

In fact, defaultZone only needs to configure one node, and the other nodes will synchronize automatically. Start the service and you can see

After reading the above, do you have any further understanding of how to use eureka to implement a registry in springcloud? If you want to know more knowledge or related content, please follow the industry information channel, thank you for your support.

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