rancher+kubernetes负载均衡根据路径路由服务

一、注意（最大的坑）

1、从0.22.0版开始，使用注释的入口定义nginx.ingress.kubernetes.io/rewrite-target与先前版本不向后兼容。在版本0.22.0及更高版本中，必须在捕获组中显式定义请求URI中需要传递到重写路径的任何子字符串。

2、捕获组保存在编号占位符，按时间顺序，形式$1，$2... $n。这些占位符可用作rewrite-target注释中的参数。

3、官方文档链接： https://kubernetes.github.io/ingress-nginx/examples/rewrite/

二、kubernetes Ingress规则配置

注意配置中的：$2 和 something(/|$)(.*)

apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /$2
  name: rewrite
  namespace: default
spec:
  rules:
  - host: rewrite.bar.com
    http:
      paths:
      - backend:
          serviceName: http-svc
          servicePort: 80
        path: /something(/|$)(.*)

三、Rancher Ingress规则配置

访问：http:/host/model01/，请求会被发送到web-server-01工作负载中

访问：http:/host/model02/，请求会被发送到web-server-02工作负载中

访问：http:/host/model03/，请求会被发送到web-server-03工作负载中

配置如下：

This example demonstrates how to use the Rewrite annotations

Prerequisites

You will need to make sure your Ingress targets exactly one Ingress controller by specifying the ingress.class annotation, and that you have an ingress controller running in your cluster.

Deployment

Rewriting can be controlled using the following annotations:

Name	Description	Values
nginx.ingress.kubernetes.io/rewrite-target	Target URI where the traffic must be redirected	string
nginx.ingress.kubernetes.io/ssl-redirect	Indicates if the location section is accessible SSL only (defaults to True when Ingress contains a Certificate)	bool
nginx.ingress.kubernetes.io/force-ssl-redirect	Forces the redirection to HTTPS even if the Ingress is not TLS Enabled	bool
nginx.ingress.kubernetes.io/app-root	Defines the Application Root that the Controller must redirect if it's in '/' context	string
nginx.ingress.kubernetes.io/use-regex	Indicates if the paths defined on an Ingress use regular expressions	bool

Examples

Rewrite Target

Attention

Starting in Version 0.22.0, ingress definitions using the annotation nginx.ingress.kubernetes.io/rewrite-target are not backwards compatible with previous versions. In Version 0.22.0 and beyond, any substrings within the request URI that need to be passed to the rewritten path must explicitly be defined in a capture group.

Note

Captured groups are saved in numbered placeholders, chronologically, in the form $1, $2 ... $n. These placeholders can be used as parameters in the rewrite-target annotation.

Create an Ingress rule with a rewrite annotation:

$ echo '
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /$2
  name: rewrite
  namespace: default
spec:
  rules:
  - host: rewrite.bar.com
    http:
      paths:
      - backend:
          serviceName: http-svc
          servicePort: 80
        path: /something(/|$)(.*)
' | kubectl create -f -

In this ingress definition, any characters captured by (.*) will be assigned to the placeholder $2, which is then used as a parameter in the rewrite-target annotation.

For example, the ingress definition above will result in the following rewrites:

• rewrite.bar.com/something rewrites to rewrite.bar.com/
• rewrite.bar.com/something/ rewrites to rewrite.bar.com/
• rewrite.bar.com/something/new rewrites to rewrite.bar.com/new

App Root¶

Create an Ingress rule with a app-root annotation:

$ echo "
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
  annotations:
    nginx.ingress.kubernetes.io/app-root: /app1
  name: approot
  namespace: default
spec:
  rules:
  - host: approot.bar.com
    http:
      paths:
      - backend:
          serviceName: http-svc
          servicePort: 80
        path: /
" | kubectl create -f -

Check the rewrite is working

$ curl -I -k http://approot.bar.com/
HTTP/1.1 302 Moved Temporarily
Server: nginx/1.11.10
Date: Mon, 13 Mar 2017 14:57:15 GMT
Content-Type: text/html
Content-Length: 162
Location: http://stickyingress.example.com/app1
Connection: keep-alive






https://kubernetes.github.io/ingress-nginx/examples/rewrite/