Nacos registry

● Know and install Nacos
● Nacos Quick start
● Nacos Service hierarchical storage model
● Nacos Environmental isolation

know Nacos

Nacos It's Alibaba's product , Now it is SpringCloud A component of . comparison Eureka More features , It is highly popular in China .

nacos Service hierarchical storage model

Cross cluster invocation of services
Select the local cluster service as much as possible for service invocation , Cross cluster call latency is high
When the local cluster is not accessible , Then visit other clusters

Service cluster properties
1. modify application.yml attribute , Add the following

spring:
  cloud:
    nacos:
      server-addr: localhost:8001 #nacos Service address of 
      discovery:
        cluster-name: SH # Cluster name   here SH Refers to Shanghai 

2. stay nacos The console can see the cluster changes ：

summary

1.Nacos Service hierarchical storage model
① The first level is service , for example userservice
② The second level is the cluster , For example, Hangzhou and Shanghai
③ The third level is the instance , For example, a certain computer room in Hangzhou has deployed userservice Service area of
2. How to set the cluster properties of an instance
① modify application.yml file , add to spring.cloud.nacos.discovery.cluster-name Attribute is enough

According to cluster load balancing

1. modify order-service Medium application.yml, Set the cluster to HZ：

spring:
  cloud:
    nacos:
      server-addr: localhost:8001 #nacos Service address of 
      discovery:
        cluster-name: HZ # Cluster name   here HZ Hangzhou 

2. And then in order-service Set load balancing in IRule by NacosRule, This rule gives priority to finding services in the same cluster as yourself ：

userservice: # The name of the micro service to be configured 
  ribbon:
    NFLoadBalancerRuleClassName: com.alibaba.cloud.nacos.ribbon.NacosRule  # Load balancing rules 

3. Pay attention to user-service The weight of is set to 1.

NacosRule Load balancing strategy
① The same cluster service list is preferred
② The local cluster cannot find the provider , Just go to other clusters to find , And will report a warning
③ After determining the list of available instances , Then random load balancing is used to select examples

Load balancing according to weight

This scenario will appear in the actual deployment ：

• There are differences in the performance of server devices , The machine where some examples are located has good performance , Others are poor , We want better machines to take on more user requests
• nacos Weight configuration is provided to control access frequency , The greater the weight, the higher the access frequency
  1. stay nacos The console can set the weight value of the instance , First, select the Edit button behind the instance
  
  2. Set the weight value to 0.1, Tests can find 8082 The frequency of being visited is greatly reduced
  

Instance weight control
① nacos You can set the weight value of the instance ,0~1 Between
② The higher the weight of multiple instances in the same cluster, the higher the frequency of access
③ The weight is set to 0 Will not be accessed at all

Environmental isolation -namespace

Nacos The outermost layer of both service storage and data storage in is called namespace Things that are , Used for the outermost isolation

1. stay Nacos The console can create namespace, Used to isolate different environments

2. Then fill in a new namespace information

3. After saving, you will see the name of this namespace in the console id:

4. modify oder-service Of application.yml, add to namespace:

spring: 
  cloud:
    nacos:
      server-addr: localhost:8001 #nacos Service address 
      discovery:
        cluster-name: HZ # Cluster name 
        namespace: c072b17e-a5a6-4c23-aff3-aa83749eefa0 # Namespace   fill id

5. restart order-service after , Check the console again

6. Visit at this time order-service, because namespace Different , Will lead to the loss of userservice The console will report an error ：

Nacos Environmental isolation
① namespace It's used for environmental isolation
② Every namespace There is only one id
③ Different namespace The service under is not visible

Nacos and Eureka contrast

nacos Registry detail analysis

Temporary and non temporary instances
Service registered to nacos when , You can choose to register as a temporary instance or a temporary instance , Set... Through the following configuration ：

spring:
  cloud:
    nacos:
      server-addr: localhost:8001 #nacos Service address 
      discovery:
        ephemeral: false # Whether it is a temporary instance 

Nacos and eureka Common ground
① Both support service registration and service pull
② All support service providers' heartbeat for health detection
Nacos and eureka difference
① Nacos Support the server to actively monitor the status of service providers ： The temporary instance adopts heartbeat mode , Active detection mode is adopted for non temporary instances
② The temporary instance will be kicked out if its heartbeat is abnormal , Non temporary instances will not be kicked out
③ Nacos Message push mode for hosting service list changes , The service list is updated more timely
④ Nacos The cluster adopts... By default AP The way , When there are non temporary instances in the cluster , use CP Pattern ;Eureka use AP Pattern

Thank you for your participation ：

Video address ：https://www.bilibili.com/video/BV1LQ4y127n4?p=17