Kubernetes Nginx Ingress 使用主机文件返回 502 Bad Gateway

如何解决Kubernetes Nginx Ingress 使用主机文件返回 502 Bad Gateway

在成功部署应用程序（pod 看起来正常，日志正常）后，我创建了 ClusterIP 服务，然后创建了 Nginx Ingress 并将主机添加到主机文件中。当我尝试访问 posts.com/posts 时，我收到 502 bad gateway 错误。

ingress-srv.yaml

apiVersion: networking.k8s.io/v1
kind: Ingress
Metadata:
  name: ingress-srv
  annotations:
    Nginx.ingress.kubernetes.io/service-upstream: "true"
    Nginx.ingress.kubernetes.io/rewrite-target: /
spec:
  rules:
  - host: posts.com
    http:
      paths:
      - path: /posts
        pathType: Prefix
        backend:
          service:
            name: posts-clusterip-srv
            port:
              number: 4000

posts-depl.yaml

apiVersion: apps/v1
kind: Deployment
Metadata:
  name: posts-depl
spec:
  replicas: 1
  selector:
    matchLabels:
      app: posts
  template:
    Metadata:
      labels:
        app: posts
    spec:
      containers:
        - name: posts
          image: myUser/posts
          resources:
            limits:
              memory: 512Mi
              cpu: "1"
            requests:
              memory: 256Mi
              cpu: "0.2"
          ports:
            - containerPort: 4000
---
apiVersion: v1
kind: Service
Metadata:
  name: posts-clusterip-srv
spec:
  selector:
    app: posts
  ports:
    - name: posts
      protocol: TCP
      port: 4000
      targetPort: 4000

##
# Host Database
#
# localhost is used to configure the loopback interface
# when the system is booting.  Do not change this entry.
##
127.0.0.1   localhost
255.255.255.255 broadcasthost
::1 localhost
127.0.0.1   posts.com
# Added by Docker Desktop
# To allow the same kube context to work on the host and the container:
127.0.0.1 kubernetes.docker.internal
# End of section

Dockerfile

FROM node:alpine

workdir /app
copY package.json ./
RUN npm install
copY ./ ./

CMD ["npm","start"]

可能是什么问题，至少我应该在哪里寻找？

解决方法

我看到两个问题 - 试试这些，如果有帮助，请告诉我：

您的 Ingress 清单中缺少 pathType。必须提供此项，否则 Kubernetes 将无法理解它是精确匹配还是前缀匹配。阅读更多here。（我看到@Sahadat 正确地指出了这一点，但不知何故删除了他的答案）。
您的部署清单中缺少端口号，应该如下所示：

spec:
  containers:
    - name: posts
      image: myuser/posts
      ports:
      - containerPort: 4000

更新 1：

另一个潜在问题可能是您的主机文件中的此条目 - 127.0.0.1 posts.com，请删除它并尝试。