Kubernetes Ingress路径重写

Question

我正在对Kubernetes上的一些服务运行Ingress，虽然服务正在重新定向到那些集群in (有点正确)，但我不知道如何正确解析那些基本路径之后的路径，例如，如果/路径中有Tomcat和路径/nginx上的Nginx，那么在/之后的任何Tomcat路径都不会解析，甚至/也不会解析任何Nginx路径。我已经在我的nginx.ingress.kubernetes.io/rewrite-target: /中设置了ingress.yaml

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: tomcat-ingress
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /
  namespace: kube-system
spec:
  rules:
  - http:
      paths:
      - path: /
        backend:
          serviceName: tomcat-deployment-service 
          servicePort: 8080
      - path: /nginx
        backend:
          serviceName: nginx-deployment-service 
          servicePort: 80

例如，如果Tomcat需要一个/main.css文件，浏览器将尝试获取/main.css，但这将返回default-backend。

此外，如果我试图访问Nginx服务器上的/nginx (试图访问/)，则Nginx表示没有找到/nginx (显然)。

2019/03/02 08:12:04 [error] 8#8: *343 open() "/usr/share/nginx/html/nginx" failed (2: No such file or directory), client: 10.128.0.7, server: localhost, request: "GET /nginx HTTP/1.1", host: "REDACTED_SERVER_IP"
10.128.0.7 - - [02/Mar/2019:08:12:04 +0000] "GET /nginx HTTP/1.1" 404 153 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:65.0) Gecko/20100101 Firefox/65.0" "REDACTED_CLIENT_IP, REDACTED_SERVER_IP"
10.40.1.1 - - [02/Mar/2019:08:12:05 +0000] "GET /nginx HTTP/1.1" 404 153 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:65.0) Gecko/20100101 Firefox/65.0" "REDACTED_CLIENT_IP, REDACTED_SERVER_IP"
2019/03/02 08:12:05 [error] 8#8: *344 open() "/usr/share/nginx/html/nginx" failed (2: No such file or directory), client: 10.40.1.1, server: localhost, request: "GET /nginx HTTP/1.1", host: "REDACTED_SERVER_IP"

在从服务中查看路径的起始部分之后，如何在指定的path ingress.yaml 解析之后创建路径？

即

1. 如果Tomcat是通过/tomcat路径进入的，我如何使/tomcat/main.css在Tomcat服务器上显示为/main.css (而不是解析为默认回退)？
2. 如果Nginx是进入/nginx的路径，我如何使/nginx在Nginx服务器上显示为/ (而不是以/nginx的形式出现)？

我以为这就是/rewrite-target应该做的。

我需要使用通配符还是什么的？

我的入口处如下：

Name:             tomcat-ingress
Namespace:        kube-system
Address:          REDACTED_SERVER_IP
Default backend:  default-http-backend:80 (10.40.0.6:8080)
Rules:
  Host  Path  Backends
  ----  ----  --------
  *         
        /        tomcat-deployment-service:8080 (10.40.2.15:8080)
        /nginx   nginx-dep-ser:80 (10.40.0.26:80,10.40.1.46:80)
Annotations:
  ingress.kubernetes.io/url-map:                     k8s-um-kube-system-tomcat-ingress--b0fc8aa23db1001d
  kubectl.kubernetes.io/last-applied-configuration:  {"apiVersion":"extensions/v1beta1","kind":"Ingress","metadata":{"annotations":{"nginx.ingress.kubernetes.io/rewrite-target":"/"},"name":"tomcat-ingress","namespace":"kube-system"},"spec":{"rules":[{"http":{"paths":[{"backend":{"serviceName":"tomcat-deployment-service","servicePort":8080},"path":"/"},{"backend":{"serviceName":"nginx-dep-ser","servicePort":80},"path":"/nginx"}]}}]}}

  nginx.ingress.kubernetes.io/rewrite-target:  /
  ingress.kubernetes.io/backends:              {"k8s-be-30985--b0fc8aa23db1001d":"HEALTHY","k8s-be-31229--b0fc8aa23db1001d":"HEALTHY","k8s-be-32736--b0fc8aa23db1001d":"HEALTHY"}
  ingress.kubernetes.io/forwarding-rule:       k8s-fw-kube-system-tomcat-ingress--b0fc8aa23db1001d
  ingress.kubernetes.io/target-proxy:          k8s-tp-kube-system-tomcat-ingress--b0fc8aa23db1001d
Events:
  Type    Reason  Age                From                      Message
  ----    ------  ----               ----                      -------
  Normal  CREATE  33m                nginx-ingress-controller  Ingress kube-system/tomcat-ingress
  Normal  ADD     33m                loadbalancer-controller   kube-system/tomcat-ingress
  Normal  UPDATE  3m (x65 over 33m)  nginx-ingress-controller  Ingress kube-system/tomcat-ingress
  Normal  CREATE  3m (x31 over 33m)  loadbalancer-controller   ip: REDACTED_SERVER_IP

Answer 1

我假设您有最近版本的入口控制器，并且根据文档

从0.22.0版本开始，使用注释nginx.ingress.kubernetes.io/rewrite-target的入口定义与以前的版本不向后兼容。在0.22.0及更高版本中，请求URI中任何需要传递到重写路径的子字符串都必须在捕获组中显式定义。

例如：

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /$1
  name: tomcat-ingress
  namespace: default 
spec:
  rules:
  - host: rewrite.bar.com
    http:
      paths:
      - backend:
          serviceName: tomcat-deployment-service
          servicePort: 8080
        path: /tomcat/?(.*)
      - backend:
          serviceName: nginx-deployment-service
          servicePort: 80
        path: /nginx/?(.*)

您的当前配置仅适用于最新版本的入口控制器，对于/和/nginx目的地非常有效。

另一件重要的事情是，应该在与它所引用的服务相同的名称空间中创建important对象。否则，ingress通常会返回503 Service Temporarily Unavailable错误。

而且它不允许引用serviceName中不同名称空间中的服务

DNS-1035标签必须由小写字母数字字符或“-”组成，以字母字符开头，以字母数字字符结尾(例如，“my-name”或“abc-123”，用于验证的正则表达式是“abc？”)。