如果容器监听端口9376，那么 发送:9376

如果服务在端口80上侦听，则 端口:80

然后服务端口配置如下所示

ports:
 - protocol: TCP
   port: 80
   targetPort: 9376

最后，请求接收到服务的端口，并在pod的targetPort上转发。

“目标端口”是容器正在运行的端口。

端口:端口将流量从服务重定向到容器。

公开部署

  master $ kubectl get deployments
NAME         READY   UP-TO-DATE   AVAILABLE   AGE

nginx        1/1     1            1           31s
master $ kubectl expose deployment nginx --name=nginx-svc --port=8080 --target-port=80
service/nginx-svc exposed

master $ kubectl get svc

NAME         TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)    AGE

nginx-svc    ClusterIP   10.107.209.151   <none>        8080/TCP   5s

NodePort:服务对外访问的端口。

希望这是答案。

我认为形象是最好的描述。

目标器端口说明

# pod file
apiVersion: v1
kind: Pod
metadata: 
  name: pod_name
  labels: 
     name: pod_ref
spec: 
  containers:
  - name: docker-container
    image: python:3:11
    ports: 
    - containerPort: 5000 # this is the target port which we need to access (target) from service file

---
apiVersion: v1
kind: Service
metadata: 
   name: service_config
   labels: 
     name: service_config_ref
spec:
   type: NodePort
   selector:
     name: pod_ref  # same as pod metadata match labels 
     ports:
      - targetPort: 5000 # this is where the pod is listening 
        port: 80 # this is where this service (this file) is going to listen. 
                 # If you call the port 80, it will reach the service, then the service will forward the port to port:5000

这个答案是参考Kubernetes的文档以及其他答案:

https://kubernetes.io/docs/concepts/services-networking/connect-applications-service/:

targetPort:容器接收流量的端口，

port:是抽象的服务端口，它可以是其他pod用来访问服务的任何端口

https://kubernetes.io/docs/concepts/services-networking/service/:

Pods中的端口定义有名称，您可以在服务的targetPort属性中引用这些名称。即使服务中有使用单一配置名称的pod的混合物，通过不同的端口号使用相同的网络协议，这种方法也有效。

@Manikanta P上面给出的答案是正确的。然而，“Port”的解释初读时可能有点不清楚。我将用一个例子来解释:

考虑一个web应用程序，它的静态内容(首页，图像等)由httpd托管，而动态内容(例如。响应请求等)由tomcat托管。Webserver(或静态内容)由httpd在80端口提供，而Appserver(或动态内容)由tomcat在8080端口提供。

开发者想要的:用户应该能够从外部访问web服务器，但不能从外部访问应用服务器。

解决方案:服务中的web服务器的服务类型。yml将是NodePort，而Appserver的service-type在其服务中。yml将是ClusterIP。

webserver的service.yml代码:

spec:
  selector:
    app: Webserver
  type: NodePort        // written to make this service accessible from outside.
  ports:
    - nodePort: 30475   // To access from outside, type <host_IP>:30475 in browser.
      port: 5050        // (ignore for now, I will explain below).
      protocol: TCP
      targetPort: 80  // port where httpd runs inside the webserver pod.

Appserver的service.yml代码

spec:
  selector:
    app: appserver
  type: ClusterIP        // written to make this service NOT accessible from outside.
  ports:
    - port: 5050         // port to access this container internally
      protocol: TCP
      targetPort: 8080   // port where tomcat runs inside the appserver pod.

还要注意，在Webserver的httpd.conf文件中，我们将写入将用户请求重定向到应用服务器的IP。这个IP将是:host_IP:5050。

What exactly is happening here? A user writes hostIP:30475 and sees the Webserver's page. This is because it is being served by httpd at port 80 (targetport). When a user clicks a button, a request is made. This request is redirected to the Appserver because in httpd.conf file, the port 5050 is mentioned and this is the port where Appserver's container and Webserver's conatainer communicate internally. When the appserver receives the request, it is able to serve the request because of tomcat running inside it at port 8080.