kubernetes微服务之ingress-nginx

目录

[1 ingress-nginx 介绍](#1 ingress-nginx 介绍)

[2 Ingress-nginx 的工作原理](#2 Ingress-nginx 的工作原理)

[3 使用 Ingress-nginx 的步骤](#3 使用 Ingress-nginx 的步骤)

[4 部署 ingress ：](#4 部署 ingress ：)

[4.1 开启ipvs 模式](#4.1 开启ipvs 模式)

[4.2 下载部署文件](#4.2 下载部署文件)

[4.3 上传镜像到harbor](#4.3 上传镜像到harbor)

[4.4 修改文件中镜像地址,与harbor仓库路径保持一致](#4.4 修改文件中镜像地址,与harbor仓库路径保持一致)

[4.5 检查是否running](#4.5 检查是否running)

[4.6 将ingress的命名空间微服务类型改为LoadBalancer](#4.6 将ingress的命名空间微服务类型改为LoadBalancer)

[4.7 查询分配的IP](#4.7 查询分配的IP)

[5 ingress-nginx功能使用案例](#5 ingress-nginx功能使用案例)

[5.1 创建基础的ingress架构：基于路径访问](#5.1 创建基础的ingress架构：基于路径访问)

[5.1.1 创建deployment控制器验证MmetalLB是否可用](#5.1.1 创建deployment控制器验证MmetalLB是否可用)

[5.1.2 创建ingress资源类型和服务](#5.1.2 创建ingress资源类型和服务)

[5.1.3 创建 ingress 资源类型作为与内部service的一个链接](#5.1.3 创建 ingress 资源类型作为与内部service的一个链接)

[5.2 基于域名的访问](#5.2 基于域名的访问)

[5.3 建立tls加密](#5.3 建立tls加密)

[5.4 建立auth认证](#5.4 建立auth认证)

[5.5 rewrite重定向](#5.5 rewrite重定向)

---

1 ingress-nginx 介绍

Ingress-nginx 是一个广泛使用的 Kubernetes Ingress 控制器，它基于 Nginx 反向代理和负载均衡器来处理进入 Kubernetes 集群的 HTTP 和 HTTPS 流量。Ingress-nginx 提供了一个强大的工具来管理 Kubernetes 集群的入口流量，允许用户通过 Ingress 资源来定义如何将外部请求路由到集群内部的服务。

官网：

Installation Guide - Ingress-Nginx Controller (kubernetes.github.io)https://kubernetes.github.io/ingress-nginx/deploy/

2 Ingress-nginx 的工作原理

Ingress 资源：

• 用户在 Kubernetes 集群中创建 Ingress 资源，定义了如何将外部流量路由到集群内的服务。
• Ingress 资源可以包含多个规则，每个规则可以指定一个或多个路径，以及这些路径应路由到的后端服务。

Ingress 控制器：

• Ingress-nginx 控制器是一个部署在 Kubernetes 集群中的 Pod，它监视 Ingress 资源的变化。
• 当 Ingress 资源发生变化时，Ingress-nginx 控制器会更新 Nginx 的配置文件，以反映新的路由规则。

Nginx 配置：

• Ingress-nginx 控制器使用 Nginx 的模板和配置文件来生成 Nginx 的配置。
• 这些配置文件定义了如何将外部请求路由到集群内的服务，包括负载均衡、SSL 终止、重写规则等。

Nginx 服务：

• Nginx 服务是一个运行在 Kubernetes 集群中的 Pod，它使用 Ingress-nginx 控制器生成的配置文件来处理外部流量。
• Nginx 服务通常使用 NodePort 或 LoadBalancer 类型的 Service 来暴露到外部网络。

3 使用 Ingress-nginx 的步骤

部署 Ingress-nginx 控制器：

• 使用 Helm Chart 或者 Kubernetes 部署文件在集群中部署 Ingress-nginx 控制器。

创建 Ingress 资源：

• 根据需要创建 Ingress 资源，定义如何将外部流量路由到集群内的服务。

配置 Nginx 服务：

• 配置 Nginx 服务的 Service，使其能够暴露到外部网络。

测试 Ingress：

• 使用外部工具（如 curl）测试 Ingress 资源，确保流量能够正确路由到集群内的服务。

搭建云平台功能metalLB：

• MetalLB 是一个专注于解决 Kubernetes 集群内部负载均衡问题的工具，特别是在没有云提供商负载均衡器支持的环境下。它提供了类似云提供商负载均衡器的功能。

4 部署 ingress ：

ps ：

由于是裸金属状态部署ingress，是需要云平台的，而在虚拟机上并没有提供与平台负载均衡器。

所以需要使用MetalLB 使得k8s集群支持云平台功能。本章就不做介绍了，需要搭建的可以去上一章节查看

4.1 开启ipvs 模式

设置ipvs模式
[root@k8s-master yaml]# kubectl -n kube-system get configmaps 
NAME                                                   DATA   AGE
coredns                                                1      4d22h
extension-apiserver-authentication                     6      4d22h
kube-apiserver-legacy-service-account-token-tracking   1      4d22h
kube-proxy                                             2      4d22h
kube-root-ca.crt                                       1      4d22h
kubeadm-config                                         1      4d22h
kubelet-config                                         1      4d22h

[root@k8s-master yaml]# kubectl -n kube-system edit configmaps kube-proxy 
apiVersion: kubeproxy.config.k8s.io/v1alpha1
kind: KubeProxyConfiguration
mode: "ipvs"
ipvs:
  strictARP: true

[root@k8s-master ~]# kubectl -n kube-system get  pods   | awk '/kube-proxy/{system("kubectl -n kube-system delete pods "$1)}'

4.2 下载部署文件

[root@k8s-master ~]# wget https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v1.11.2/deploy/static/provider/baremetal/deploy.yaml

4.3 上传镜像到harbor

# 本地镜像导入 并打标签
[root@k8s-master ingress]# docker tag \
a80c8fd6e522 reg.shuyan.com/ingress-nginx/controller:v1.11.2

[root@k8s-master ingress]# docker tag  \
ce263a8653f9 reg.shuyan.com/ingress-nginx/kube-webhook-certgen:v1.4.3


[root@k8s-master ingress]# docker push reg.shuyan.com/ingress-nginx/controller:v1.11.2
[root@k8s-master ingress]# docker push reg.shuyan.com/ingress-nginx/kube-webhook-certgen:v1.4.3

[root@k8s-master ingress]# docker rmi \
a80c8fd6e522 \
ce263a8653f9 \
reg.shuyan.com/ingress-nginx/controller:v1.11.2 \
reg.shuyan.com/ingress-nginx/kube-webhook-certgen:v1.4.3

4.4 修改文件中镜像地址,与harbor仓库路径保持一致

[root@k8s-master ~]# vim deploy.yaml
445         image: ingress-nginx/controller:v1.11.2
546         image: ingress-nginx/kube-webhook-certgen:v1.4.3
599         image: ingress-nginx/kube-webhook-certgen:v1.4.3

[root@k8s-master ingress]# kubectl apply -f deploy.yaml

4.5 检查是否running

[root@k8s-master ingress]# kubectl -n ingress-nginx get pods 
NAME                                       READY   STATUS      RESTARTS   AGE
ingress-nginx-admission-create-nfjbh       0/1     Completed   0          10h
ingress-nginx-admission-patch-wp7zd        0/1     Completed   1          10h
ingress-nginx-controller-bb7d8f97c-r6z69   1/1     Running     0          10h

4.6 将ingress的命名空间微服务类型改为LoadBalancer

[root@k8s-master ingress]#  kubectl -n ingress-nginx \
edit service ingress-nginx-controller

 51   type: LoadBalancer

4.7 查询分配的IP

[root@k8s-master ingress]# kubectl -n ingress-nginx get svc
NAME                                 TYPE           CLUSTER-IP     EXTERNAL-IP       PORT(S)                      AGE
ingress-nginx-controller             LoadBalancer   10.97.25.16    192.168.239.201   80:30467/TCP,443:31166/TCP   10h
ingress-nginx-controller-admission   ClusterIP      10.99.91.236   <none>            443/TCP                      10h

# 创建 Ingress 的命令:
kubectl create ingress NAME --rule=host/path=service:port[,tls[=secretname]] [options]

# 常用选项
host/path # 服务对应的 FQDN 和 URL
--annotation=[] # 注解信息，格式为 "annotation=value"
--rule=[] # 代理规则，格式为 "host/path=service:port[,tls=secretname]"
--class='' # 此 Ingress 适配的 Ingress Class

# 基于 URI 方式代理不同应用的请求时，后端应用的 URI 若与代理时使用的 URI 不同，则需要启用 URL Rewrite 完成 URI 的重写
# Ingress-Nginx 支持使用 "annotation nginx.ingress.kubernetes.io/rewrite-target" 注解进行

5 ingress-nginx功能使用案例

5.1 创建基础的ingress架构：基于路径访问

5.1.1 创建deployment控制器验证MmetalLB是否可用

创建两个deployment资源类型命名为myapp-v1 与 v2

[root@k8s-master ingress]# kubectl create deployment myapp-v1 \
--image myapp:v1 --dry-run=client -o yaml > myapp-v1.yml

[root@k8s-master ingress]# kubectl create deployment myapp-v2 \
--image myapp:v2 --dry-run=client -o yaml > myapp-v2.yml

[root@k8s-master ingress]# vim myapp-v1.yml

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: myapp-v1
  name: myapp-v1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: myapp-v1
  template:
    metadata:
      labels:
        app: myapp-v1
    spec:
      containers:
      - image: myapp:v1
        name: myapp

[root@k8s-master ingress]# vim myapp-v2.yml
apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: myapp-v2
  name: myapp-v2
spec:
  replicas: 1
  selector:
    matchLabels:
      app: myapp-v2
  template:
    metadata:
      labels:
        app: myapp-v2
    spec:
      containers:
      - image: myapp:v2
        name: myapp



# 声明资源类型
[root@k8s-master ingress]# kubectl apply -f myapp-v1.yml
[root@k8s-master ingress]# kubectl apply -f myapp-v1.yml

# 查看是否创建成功

[root@k8s-master ingress]# kubectl get deployments.apps 
NAME       READY   UP-TO-DATE   AVAILABLE   AGE
myapp-v1   1/1     1            1           85m
myapp-v2   1/1     1            1           85m

# 查看集群IP
[root@k8s-master ingress]# kubectl get pods -o wide 
NAME                        READY   STATUS    RESTARTS   AGE   IP            NODE        NOMINATED NODE   READINESS GATES
myapp-v1-7479d6c54d-x2zvr   1/1     Running   0          86m   10.244.2.51   k8s-node2   <none>           <none>
myapp-v2-7cd6d597d-gmgt6    1/1     Running   0          86m   10.244.1.43   k8s-node1   <none>           <none>

# 测试集群内是否可访问
[root@k8s-master ingress]# curl 10.244.2.51
Hello MyApp | Version: v1 | <a href="hostname.html">Pod Name</a>
[root@k8s-master ingress]# curl 10.244.1.43
Hello MyApp | Version: v2 | <a href="hostname.html">Pod Name</a>

5.1.2 创建ingress资源类型和服务

使用ingress进行七层与外界通讯

由于ingress 类型是由外界传到ingress再由ingress传给内部的service 所以需要暴露端口需要创建service 进行连通

myapp-v1添加微服务

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: myapp-v1
  name: myapp-v1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: myapp-v1
  template:
    metadata:
      labels:
        app: myapp-v1
    spec:
      containers:
      - image: myapp:v1
        name: myapp
--- 
apiVersion: v1
kind: Service
metadata:
  labels:
    app: myapp-v1
  name: myapp-v1
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 80
  selector:
    app: myapp-v1

myapp-v2添加微服务

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: myapp-v2
  name: myapp-v2
spec:
  replicas: 1
  selector:
    matchLabels:
      app: myapp-v2
  template:
    metadata:
      labels:
        app: myapp-v2
    spec:
      containers:
      - image: myapp:v2
        name: myapp
---
apiVersion: v1
kind: Service
metadata:
  labels:
    app: myapp-v2
  name: myapp-v2
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 80
  selector:
    app: myapp-v2

重新声明更新

[root@k8s-master ingress]# kubectl apply -f myapp-v1.yml
[root@k8s-master ingress]# kubectl apply -f myapp-v2.yml

[root@k8s-master ingress]# kubectl get service
NAME         TYPE           CLUSTER-IP       EXTERNAL-IP       PORT(S)        AGE
kubernetes   ClusterIP      10.96.0.1        <none>            443/TCP        5d11h
myapp-v1     ClusterIP      10.108.70.49     <none>            80/TCP         91m
myapp-v2     ClusterIP      10.101.121.115   <none>            80/TCP         86m

5.1.3 创建 ingress 资源类型作为与内部service的一个链接

[root@k8s-master ingress]# kubectl create ingress webcluster \
--rule '*/=shuyan-svc:80' --dry-run=client -o yaml

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: webcluster
spec:
  rules:
  - host: '*'
    http:
      paths:
      - backend:
          service:
            name: shuyan-svc
            port:
              number: 80
        path: /
        pathType: Exact
status:
  loadBalancer: {}

[root@k8s-master ingress]# kubectl create ingress webcluster \
--rule '*/=shuyan-svc:80' --dry-run=client -o yaml > shuyan-inccress.yml

[root@k8s-master ingress]# vim shuyan-inccress.yml
## 以下是修改之后 的
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: webcluster
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /    # 访问路径后加任何内容都被定向到/
spec:
  ingressClassName: nginx
  rules:
  - http:
      paths:
      - backend:
          service:
            name: myapp-v1
            port:
              number: 80
        path: /v1            # 定义访问路径为v1
        pathType: Prefix

      - backend:
          service:
            name: myapp-v2
            port:
              number: 80
        path: /v2            # 定义访问路径为v2
        pathType: Prefix

声明ingress类型

[root@k8s-master ingress]# kubectl apply -f shuyan-inccress.yml

查看ingress分配的地址

[root@k8s-master ingress]# kubectl -n ingress-nginx get services 
NAME                                 TYPE           CLUSTER-IP     EXTERNAL-IP       PORT(S)                      AGE
ingress-nginx-controller             LoadBalancer   10.97.25.16    192.168.239.201   80:30467/TCP,443:31166/TCP   11h
ingress-nginx-controller-admission   ClusterIP      10.99.91.236   <none>            443/TCP                      11h

访问分配的地址

[root@complete ~]# curl 192.168.239.201/v1
Hello MyApp | Version: v1 | <a href="hostname.html">Pod Name</a>
[root@complete ~]# curl 192.168.239.201/v2
Hello MyApp | Version: v2 | <a href="hostname.html">Pod Name</a>

5.2 基于域名的访问

[root@k8s-master ingress]# vim shuyan-inccress.yml

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: webcluster
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /
spec:
  ingressClassName: nginx
  rules:
  - host: myapp-v1.shuyan.com    # v1 域名
    http:
      paths:
      - backend:
          service:
            name: myapp-v1
            port:
              number: 80
        path: /
        pathType: Prefix

  - host: myapp-v2.shuyan.com    # v2 域名
    http:
      paths:
      - backend:
          service:
            name: myapp-v2
            port:
              number: 80
        path: /
        pathType: Prefix

声明修改后代码

[root@k8s-master ingress]# kubectl apply -f shuyan-inccress.yml

查看是否创建成功

[root@k8s-master ingress]# kubectl describe ingress webcluster 

在集群之外的主机做域名解析

[root@complete ~]# vim /etc/hosts 
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.239.20  complete reg.shuyan.com
192.168.239.110 k8s-node1
192.168.239.120 k8s-node2
192.168.239.100 k8s-master
192.168.239.201 myapp-v1.shuyan.com  myapp-v2.shuyan.com # 添加解析

[root@complete ~]# curl myapp-v1.shuyan.com
Hello MyApp | Version: v1 | <a href="hostname.html">Pod Name</a>
[root@complete ~]# curl myapp-v2.shuyan.com
Hello MyApp | Version: v2 | <a href="hostname.html">Pod Name</a>

5.3 建立tls加密

建立证书

这条命令创建了一个名为 web-tls-secret 的 Secret，其中包含了你之前生成的 TLS 证书 (tls.crt) 和私钥 (tls.key)。Secret 是 Kubernetes 中用于存储敏感信息的对象，如密码、密钥等。

创建证书

[root@k8s-master ingress]# openssl req -newkey rsa:2048 \
-nodes -keyout tls.key -x509 -days 365 \
-subj "/CN=nginxsvc/O=nginxsvc" -out tls.crt

[root@k8s-master ingress]# kubectl describe secrets web-tls-secret 
Name:         web-tls-secret
Namespace:    default
Labels:       <none>
Annotations:  <none>

Type:  kubernetes.io/tls

Data
====
tls.crt:  1164 bytes
tls.key:  1704 bytes

[root@k8s-master ingress]# kubectl get secrets web-tls-secret -o yaml

[root@k8s-master ingress]# vim myapp-v1.yml 
apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: myapp-v1
  name: myapp-v1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: myapp-v1
  template:
    metadata:
      labels:
        app: myapp-v1
    spec:
      containers:
      - image: myapp:v1
        name: myapp
--- 
apiVersion: v1
kind: Service
metadata:
  labels:
    app: myapp-v1
  name: myapp-v1
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 80
  selector:
    app: myapp-v1

[root@k8s-master ingress]# vim ingress.yml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: webcluster
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /
spec:
  tls:                # 使用tls
  - hosts:
    - myapp-v1.shuyan.com
    secretName: web-tls-secret    # 指定secret资源类型的名称
  ingressClassName: nginx
  rules:
  - http:
      paths:
      - backend:
          service:
            name: myapp-v1
            port:
              number: 80
        path: /
        pathType: Prefix

删除原有的，声明新的

[root@k8s-master ingress]# kubectl delete -f shuyan-inccress.yml 

[root@k8s-master ingress]# kubectl apply -f ingress.yml 

查看是否成功

[root@k8s-master ingress]# kubectl describe ingress webcluster 
Name:             webcluster
Labels:           <none>
Namespace:        default
Address:          192.168.239.110
Ingress Class:    nginx
Default backend:  <default>
TLS:
  web-tls-secret terminates myapp-v1.shuyan.com
Rules:
  Host        Path  Backends
  ----        ----  --------
  *           
              /   myapp-v1:80 (10.244.2.51:80)
Annotations:  nginx.ingress.kubernetes.io/rewrite-target: /
Events:
  Type    Reason  Age                    From                      Message
  ----    ------  ----                   ----                      -------
  Normal  Sync    3m46s (x2 over 4m17s)  nginx-ingress-controller  Scheduled for sync

网页输入认证

5.4 建立auth认证

[root@k8s-master ingress]# yum install httpd-tools

# 创建本地文件为auth 用户名为shuyan
[root@k8s-master ingress]# htpasswd -cm auth shuyan
New password: 
Re-type new password: 
Adding password for user shuyan

[root@k8s-master ingress]# ls | grep auth 
auth

[root@k8s-master ingress]# cat auth 
shuyan:$apr1$Zqqr6uJj$a0Kb0nUK2CiqXYP7OugYj1

[root@k8s-master ingress]# kubectl create secret generic auth-web \
--from-file /root/ingress/auth 

查看本地导入的资源类型

[root@k8s-master ingress]# kubectl describe secrets auth-web 
Name:         auth-web
Namespace:    default
Labels:       <none>
Annotations:  <none>

Type:  Opaque

Data
====
auth:  45 bytes
[root@k8s-master ingress]# kubectl get secrets auth-web -o yaml
apiVersion: v1
data:
  auth: c2h1eWFuOiRhcHIxJFpxcXI2dUpqJGEwS2IwblVLMkNpcVhZUDdPdWdZajEK
kind: Secret
metadata:
  creationTimestamp: "2024-09-08T11:42:25Z"
  name: auth-web
  namespace: default
  resourceVersion: "733478"
  uid: 84cc365b-de63-40f3-b134-75ed984a1692
type: Opaque

建立ingress2基于用户认证的yaml文件

[root@k8s-master ingress]# vim ingress2.yml 
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: ingress-auth
  annotations:
    nginx.ingress.kubernetes.io/auth-type: basic        # 定义认证类型
    nginx.ingress.kubernetes.io/auth-secret: auth-web   # 选定导入的本地加密文件名称
    nginx.ingress.kubernetes.io/auth-realm: "Please input username and password"    # 打印一条语句
    nginx.ingress.kubernetes.io/rewrite-target: /
spec:
  tls:
  - hosts:
    - myapp-v1.shuyan.com
    secretName: web-tls-secret
  ingressClassName: nginx
  rules:
  - http:
      paths:
      - backend:
          service:
            name: myapp-v1
            port:
              number: 80
        path: /
        pathType: Prefix

删除旧的并创建新的

[root@k8s-master ingress]# kubectl delete -f ingress.yml 
[root@k8s-master ingress]# kubectl apply -f ingress2.yml 

查看认证文件资源类型

[root@k8s-master ingress]# kubectl describe ingress ingress-auth 
Name:             ingress-auth
Labels:           <none>
Namespace:        default
Address:          
Ingress Class:    nginx
Default backend:  <default>
TLS:
  web-tls-secret terminates myapp-v1.shuyan.com
Rules:
  Host        Path  Backends
  ----        ----  --------
  *           
              /   myapp-v1:80 (10.244.2.51:80)
Annotations:  nginx.ingress.kubernetes.io/auth-realm: Please input username and password
              nginx.ingress.kubernetes.io/auth-secret: auth-web
              nginx.ingress.kubernetes.io/auth-type: basic
              nginx.ingress.kubernetes.io/rewrite-target: /
Events:
  Type    Reason  Age   From                      Message
  ----    ------  ----  ----                      -------
  Normal  Sync    27s   nginx-ingress-controller  Scheduled for 

实现效果

5.5 rewrite重定向

基于正则表达式的重定向

[root@k8s-master ingress]# vim ingress3.yml 

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: ingress-rewite
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /$2
    nginx.ingress.kubernetes.io/use-regex: "true"
spec:
  ingressClassName: nginx
  rules:
  - http:
      paths:
      - backend:
          service:
            name: myapp-v1
            port:
              number: 80
        path: /
        pathType: Prefix

      - backend:
          service:
            name: myapp-v2
            port:
              number: 80
        path: /shuyan(/|$)(.*)
        pathType: ImplementationSpecific
    host: myapp-v1.shuyan.com


nginx.ingress.kubernetes.io/rewrite-target: /$2：
这个注解告诉 Nginx Ingress 控制器，对于匹配 /shuyan/(/|$)(.*) 的路径，
将路径重写为 / 后面加上 $2。

$2 是正则表达式中捕获的第二个分组，即 / 或空字符串后面的所有内容。
例如，请求 https://myapp-v1.shuyan.com/shuyan/some/path 将被重写为 /some/path。


根路径请求：
客户端请求 https://myapp-v1.shuyan.com/，直接转发到 myapp-v1 服务。

带 /shuyan 的路径请求：
客户端请求 https://myapp-v1.shuyan.com/shuyan/some/path，
匹配 /shuyan/(/|$)(.*)，路径重写为 /some/path，然后转发到 myapp-v2 服务。

声明并查看状态

[root@k8s-master ingress]# kubectl delete -f ingress2.yml 
[root@k8s-master ingress]# kubectl apply -f ingress3.yml


[root@k8s-master ingress]# kubectl describe ingress ingress-rewite 
Name:             ingress-rewite
Labels:           <none>
Namespace:        default
Address:          192.168.239.110
Ingress Class:    nginx
Default backend:  <default>
Rules:
  Host                 Path  Backends
  ----                 ----  --------
  myapp-v1.shuyan.com  
                       /                  myapp-v1:80 (10.244.2.51:80)
                       /shuyan(/|$)(.*)   myapp-v2:80 (10.244.1.43:80)
Annotations:           nginx.ingress.kubernetes.io/rewrite-target: /$2
                       nginx.ingress.kubernetes.io/use-regex: true
Events:
  Type    Reason  Age                  From                      Message
  ----    ------  ----                 ----                      -------
  Normal  Sync    5m50s (x5 over 18m)  nginx-ingress-controller  Scheduled for sync

[root@complete ~]# curl myapp-v1.shuyan.com
Hello MyApp | Version: v1 | <a href="hostname.html">Pod Name</a>
[root@complete ~]# curl myapp-v1.shuyan.com/shuyan/index.html
Hello MyApp | Version: v2 | <a href="hostname.html">Pod Name</a>
[root@complete ~]# curl myapp-v1.shuyan.com/shuyan/hostname.html
myapp-v2-7cd6d597d-gmgt6

基于根目录的重定向

[root@k8s-master ingress]# vim ingress4.yml 

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: ingress-rewite
  annotations:
    nginx.ingress.kubernetes.io/app-root: /hostname.html
spec:
  ingressClassName: nginx
  rules:
  - http:
      paths:
      - backend:
          service:
            name: myapp-v1
            port:
              number: 80
        path: /
        pathType: Prefix
    host: myapp-v1.shuyan.com

声明并查看

[root@k8s-master ingress]# kubectl delete -f ingress3.yml

[root@k8s-master ingress]# kubectl apply -f ingress4.yml 

[root@k8s-master ingress]# kubectl describe ingress ingress-rewite 
Name:             ingress-rewite
Labels:           <none>
Namespace:        default
Address:          192.168.239.110
Ingress Class:    nginx
Default backend:  <default>
Rules:
  Host                 Path  Backends
  ----                 ----  --------
  myapp-v1.shuyan.com  
                       /   myapp-v1:80 (10.244.2.51:80)
Annotations:           nginx.ingress.kubernetes.io/app-root: /hostname.html
Events:
  Type    Reason  Age               From                      Message
  ----    ------  ----              ----                      -------
  Normal  Sync    9s (x2 over 16s)  nginx-ingress-controller  Scheduled for sync

[root@complete ~]# curl -L myapp-v1.shuyan.com/
myapp-v1-7479d6c54d-x2zvr


[root@complete ~]# curl  myapp-v1.shuyan.com/123/3123/ -L
<html>
<head><title>404 Not Found</title></head>
<body bgcolor="white">
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.12.2</center>
</body>
</html>

能不能写什么都会被重定向到指定目录呢？

当然可以

使用 nginx.ingress.kubernetes.io/rewrite-target注解来重写所有请求到 /hostname.html 的 Ingress 规则：

[root@k8s-master ingress]# vim ingress5.yml 

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: ingress-rewite
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /hostname.html
spec:
  ingressClassName: nginx
  rules:
  - host: myapp-v1.shuyan.com
    http:
      paths:
      - backend:
          service:
            name: myapp-v1
            port:
              number: 80
        path: /
        pathType: Prefix

[root@k8s-master ingress]# kubectl delete -f ingress4.yml 
ingress.networking.k8s.io "ingress-rewite" deleted
[root@k8s-master ingress]# kubectl apply -f ingress5.yml 
ingress.networking.k8s.io/ingress-rewite created

[root@complete ~]# curl  myapp-v1.shuyan.com/123/3123/ -L
myapp-v1-7479d6c54d-x2zvr
[root@complete ~]# curl  myapp-v1.shuyan.com/123/3123/ 
myapp-v1-7479d6c54d-x2zvr
[root@complete ~]# curl  myapp-v1.shuyan.com/123/31233123/ 
myapp-v1-7479d6c54d-x2zvr
[root@complete ~]# curl  myapp-v1.shuyan.com/123/31233123/3213 
myapp-v1-7479d6c54d-x2zvr


根据新的 Ingress 规则，所有请求都将被重写到 /hostname.html。这意味着：

请求 https://myapp-v1.shuyan.com/ 将被重写到 /hostname.html。
请求 https://myapp-v1.shuyan.com/123 也将被重写到 /hostname.html。
请求 https://myapp-v1.shuyan.com/some/path 也将被重写到 /hostname.html。