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十九 服务发布Ingress

2022-06-11  本文已影响0人  負笈在线

(一) Ingress Nginx Controller安装

首先安装Helm

# wget https://get.helm.sh/helm-v3.6.3-linux-amd64.tar.gz
# tar -zxvf helm-v3.0.0-linux-amd64.tar.gz
# mv linux-amd64/helm /usr/local/bin/helm

下载 Ingress Nginx Controller安装包

# helm repo add ingress-nginx https://kubernetes.github.io/ingress-nginx
# helm repo update
# helm pull ingress-nginx/ingress-nginx --version 4.0.1

更改对应的配置

# tar xf ingress-nginx-4.0.1.tgz
#cd ingress-nginx
#vim values.yaml

需要修改的位置

  1. Controller和admissionWebhook的镜像地址,需要将公网镜像同步至公司内网镜像仓库(和课程不一致的版本,需要自行同步gcr镜像,一样的版本可以直接用registry.cn-beijing.aliyuncs.com/dotbalo/kube-webhook-certgen:v1.0和registry.cn-beijing.aliyuncs.com/dotbalo/controller:v1.0.0)
  2. 镜像的digest值注释
  3. hostNetwork设置为true
  4. dnsPolicy设置为 ClusterFirstWithHostNet
  5. NodeSelector添加ingress: "true"部署至指定节点
  6. 类型更改为kind: DaemonSet
  7. 将ingress nginx设置为默认的ingressClass


  8. 部署ingress,给需要部署ingress的节点上打标签
# kubectl label node k8s-node02 ingress=true
# kubectl create ns ingress-nginx
# helm install ingress-nginx -n ingress-nginx .

(二) Ingress Nginx入门使用

创建一个用于学习Ingress的Namespace,之后所有的操作都在此Namespace进行:

# kubectl create ns study-ingress
namespace/study-ingress created

创建一个简单的Nginx模拟Web服务:

# kubectl create deploy nginx --image=registry.cn-beijing.aliyuncs.com/dotbalo/nginx:1.15.12 -n study-ingress

然后创建该Web容器的Service:

# kubectl expose deploy nginx --port 80 -n study-ingress

之后创建Ingress指向上面创建的Service:

# vim web-ingress.yaml 
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: nginx-ingress
  namespace: study-ingress
spec:
  ingressClassName: nginx # for k8s >= 1.22+
  rules:
  - host: nginx.test.com
    http:
      paths:
      - backend:
          service:
            name: nginx
            port:
              number: 80
        path: /
        pathType: ImplementationSpecific 

如果apiVersion是networking.k8s.io/v1beta1,对应的配置如下:

apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
  name: nginx-ingress
  namespace: study-ingress
spec:
  rules:
  - host: nginx.test.com
    http:
      paths:
      - backend:
          serviceName: nginx
          servicePort: 80
        path: /
        pathType: ImplementationSpecific

提示:本章内容均采用networking.k8s.io/v1版本创建Ingress资源,如果Kubernetes版本低于1.19,可以使用networking.k8s.io/v1beta1替代,配置可以参考上述的networking.k8s.io/v1beta1,只有backend配置不一样。

创建该Ingress:

# kubectl create -f web-ingress.yaml

将域名nginx.test.com即可访问Web服务器,如下图所示:


(三) Ingress Nginx域名重定向Redirect

在Nginx作为代理服务器时,Redirect可用于域名的重定向,比如访问old.com被重定向到new.com。Ingress可以更简单的实现Redirect功能,接下来用nginx.redirect.com作为旧域名,baidu.com作为新域名进行演示:

# vim redirect.yaml 
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    nginx.ingress.kubernetes.io/permanent-redirect: https://www.baidu.com
  name: nginx-redirect
  namespace: study-ingress
spec:
  rules:
  - host: nginx.redirect.com
    http:
      paths:
      - backend:
          service:
            name: nginx
            port:
              number: 80
        path: /
        pathType: ImplementationSpecific

使用curl访问域名nginx.redirect.com,可以看到301(请求被重定向的返回值):

# curl -I  nginx.redirect.com
HTTP/1.1 301 Moved Permanently
...
Location: https://www.baidu.com

(四) Ingress Nginx前后端分离Rewrite

创建一个应用模拟后端服务:

# kubectl create deploy backend-api --image=registry.cn-beijing.aliyuncs.com/dotbalo/nginx:backend-api -n study-ingress
deployment.apps/backend-api created

创建Service暴露该应用

# kubectl expose deploy backend-api --port 80 -n study-ingress

查看该Service的地址,并且通过/api-a访问测试:

# kubectl get svc -n study-ingress
NAME          TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)   AGE
backend-api   ClusterIP   192.168.60.190   <none>        80/TCP    5s
nginx         ClusterIP   192.168.170.24   <none>        80/TCP    3h27m
# curl 192.168.60.190/api-a
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.15.12</center>
</body>
</html>

直接访问根路径是可以的:

# curl 192.168.60.190
<h1> backend for ingress rewrite </h1>
<h2> **Path: /api-a** </h2>

通过Ingress Nginx的Rewrite功能,将/api-a重写为“/”,配置示例如下:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /$2
  name: backend-api
  namespace: study-ingress
spec:
  ingressClassName: nginx # for k8s >= 1.22+
  rules:
  - host: nginx.test.com
    http:
      paths:
      - backend:
          service:
            name: backend-api
            port:
              number: 80
        path: /api-a(/|$)(.*)
        pathType: ImplementationSpecific

再次访问nginx.test.com/api-a即可访问到后端服务:


(五) Ingress Nginx错误代码重定向

1.通过Helm进行更改

修改values.yaml如下图所示位置:



更新ConfigMap:

  config: 
    apiVersion: v1
    client_max_body_size: 20m
    custom-http-errors: "404,415,503"

更新Release:

# helm upgrade ingress-nginx -n ingress-nginx .

更新后Pod会自动重启,并且会创建一个defaultbackend:

# kubectl get po -n ingress-nginx
NAME READY STATUS RESTARTS AGE
ingress-nginx-controller-pdjvh 1/1 Running 0 95s
ingress-nginx-defaultbackend-79d64fb85f-kxlnc 1/1 Running 0         109s

更新完成以后访问一个不存在的页面,比如之前定义的nginx.test.com。 访问一个不存在的页面123,就会跳转到Error Server中的页面:

# curl nginx.test.com/123
default backend - 404

使用浏览器访问,会出现如下图所示的页面:


(六) Ingress Nginx SSL

生产环境对外的服务,一般需要配置https协议,使用Ingress也可以非常方便的添加https的证书。
由于我们是学习环境,并没有权威证书,所以需要使用OpenSSL生成一个测试证书。如果是生产环境,证书为在第三方公司购买的证书,无需自行生成:

# openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout tls.key -out tls.crt -subj "/CN=nginx.test.com"
Generating a 2048 bit RSA private key
.....+++
............................+++
writing new private key to 'tls.key'
-----
# kubectl create secret tls ca-secret --cert=tls.crt --key=tls.key  -n study-ingress
secret/ca-secret created

配置Ingress添加TLS配置:

# vim ingress-ssl.yaml 
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  creationTimestamp: null
  name: nginx-ingress
  namespace: study-ingress
  # annotations:
    # kubernetes.io/ingress.class: nginx
spec:
  ingressClassName: nginx # for k8s >= 1.22+
  rules:
  - host: nginx.test.com
    http:
      paths:
      - backend:
          service:
            name: nginx
            port:
              number: 80
        path: /
        pathType: ImplementationSpecific
  tls:
  - hosts:
    - nginx.test.com
    secretName: ca-secret

可以看到Ingress添加TLS配置也非常简单,只需要在spec下添加一个tls字段即可:

  1. hosts:证书所授权的域名列表
  2. secretName:证书的Secret名字
  3. ingressClassName: ingress class的名字,1.22+需要配置

接下来更新该Ingress即可:

# kubectl apply -f ingress-ssl.yaml
ingress.networking.k8s.io/nginx-ingress configured

使用curl进行测试,域名已经被重定向到https:

# curl http://nginx.test.com -I
HTTP/1.1 308 Permanent Redirect
...
Location: https://nginx.test.com

使用浏览器访问,会自动跳转到https,如下图所示:


(七) Ingress Nginx匹配请求头

首先部署移动端应用:

# kubectl create deploy phone --image=registry.cn-beijing.aliyuncs.com/dotbalo/nginx:phone -n study-ingress
# kubectl expose deploy phone --port 80 -n study-ingress

Ingress实例也可以通过kubectl create进行创建,只需要一条命令即可:

# kubectl create ingress phone --rule=m.test.com/*=phone:80 -n study-ingress

部署电脑端应用:

# kubectl create deploy laptop --image=registry.cn-beijing.aliyuncs.com/dotbalo/nginx:laptop -n study-ingress
deployment.apps/laptop created
# kubectl expose deploy laptop --port 80 -n study-ingress
service/laptop exposed
# kubectl get po -n study-ingress -l app=laptop
NAME                          READY   STATUS    RESTARTS   AGE
laptop-664b565969-hpxlh   1/1     Running   0          3m22s

之后创建电脑端的Ingress,注意Ingress annotations的 nginx.ingress.kubernetes.io/server-snippet配置。Snippet配置是专门用于一些复杂的Nginx配置,和Nginx配置通用。匹配移动端实例如下:

# vim laptop-ingress.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/server-snippet: |
      set $agentflag 0;
              if ($http_user_agent ~* "(Android|iPhone|Windows Phone|UC|Kindle)" ){
                set $agentflag 1;
              }
              if ( $agentflag = 1 ) {
                return 301 http://m.test.com;
              }
  name: laptop
  namespace: study-ingress
spec:
  ingressClassName: nginx # for k8s >= 1.22+
  rules:
  - host: test.com
    http:
      paths:
      - backend:
          service:
            name: laptop
            port:
              number: 80
        path: /
        pathType: ImplementationSpecific

首先通过浏览器访问test.com,可以看到页面是Laptop:



接下来使用浏览器的开发者工具将终端类型改为iPhone,或者直接用iPhone手机访问(线上业务一般配置的都有DNS,可以直接解析域名,测试环境可能需要自己单独配置),如下图所示:



刷新页面会自动跳转至m.test.com,如下图所示:

(八) Ingress Nginx基本认证

有些网站可能需要通过密码来访问,对于这类网站可以使用Nginx的basic-auth设置密码访问,具体方法如下,由于需要使用htpasswd工具,所以需要安装httpd:

# yum install httpd -y

使用htpasswd创建foo用户的密码:

# htpasswd -c auth foo
New password: 
Re-type new password: 
Adding password for user foo
# cat auth 
foo:$apr1$okma2fx9$hdTJ.KFmi4pY9T6a2MjeS1

基于之前创建的密码文件创建Secret:

# kubectl create secret generic basic-auth --from-file=auth -n study-ingress
secret/basic-auth created

创建包含密码认证的Ingress:

# vim ingress-with-auth.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
# kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/auth-realm: Please Input Your Username and Password
    nginx.ingress.kubernetes.io/auth-secret: basic-auth
    nginx.ingress.kubernetes.io/auth-type: basic
  name: ingress-with-auth
  namespace: study-ingress
spec:
ingressClassName: nginx # for k8s >= 1.22+
  rules:
  - host: auth.test.com
    http:
      paths:
      - backend:
          service:
            name: nginx
            port:
              number: 80
        path: /
        pathType: ImplementationSpecific 
  1. nginx.ingress.kubernetes.io/auth-type:认证类型,可以是basic和digest
  2. nginx.ingress.kubernetes.io/auth-secret:密码文件的Secret名称
  3. nginx.ingress.kubernetes.io/auth-realm:需要密码认证的消息提醒

创建该Ingress,并访问测试:



输入密码后即可进入到页面,在此不再演示。

(九) Ingress Nginx黑/白名单

1.黑名单

配置黑名单禁止某一个或某一段IP,需要在Nginx Ingress的ConfigMap中配置,比如将192.168.10.130(多个配置逗号分隔)添加至黑名单:

# vim values.yaml
config:
 block-cidrs: 192.168.10.130

滚动更新Nginx Ingress:

# helm upgrade ingress-nginx -n ingress-nginx .

使用192.168.10.130主机再次访问,发现该IP已经被禁止:

# curl auth.test.com -I
HTTP/1.1 403 Forbidden
...
Connection: keep-alive

2.白名单

白名单表示只允许某个IP可以访问,直接在yaml文件中配置即可(也可以通过ConfigMap配置),比如只允许192.168.10.128访问,只需要添加一个nginx.ingress.kubernetes.io/whitelist-source-range 注释即可:

# vim auth-whitelist.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    # kubernetes.io/ingress.class: nginx # K8s >= 1.22+ 使用ingressClassName替代
    nginx.ingress.kubernetes.io/auth-realm: Please Input Your Username and Password
    nginx.ingress.kubernetes.io/auth-secret: basic-auth
    nginx.ingress.kubernetes.io/auth-type: basic
    nginx.ingress.kubernetes.io/whitelist-source-range: 192.168.10.128
  name: ingress-with-auth
  namespace: study-ingress
spec:
  ingressClassName: nginx # for k8s >= 1.22+
  rules:
  - host: auth.test.com
    http:
      paths:
      - backend:
          service:
            name: nginx
            port:
              number: 80
        path: /
        pathType: ImplementationSpecific

更新该Ingress:

# kubectl apply -f test-auth.yaml
ingress.networking.k8s.io/ingress-with-auth configured

此时192.168.10.128主机是可以访问的:

# curl auth.test.com -I
HTTP/1.1 401 Unauthorized

其它IP访问被禁止:

# curl auth.test.com -I
HTTP/1.1 403 Forbidden

(十) Ingress Nginx速率限制

有时候可能需要限制速率以降低后端压力,或者限制单个IP每秒的访问速率防止攻击。此时可以使用Nginx的rate limit进行配置。

首先没有加速率限制,使用ab进行访问,Failed为0:

# ab -c 10 -n 100 http://auth.test.com/ | grep requests
Complete requests: 100
Failed requests: 0

添加速率限制,限制只能有一个连接,只需要添加nginx.ingress.kubernetes.io/limit-connections为1即可:

# vim auth-rate-limit.yaml 
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/auth-realm: Please Input Your Username and Password
    nginx.ingress.kubernetes.io/auth-secret: basic-auth
    nginx.ingress.kubernetes.io/auth-type: basic
    nginx.ingress.kubernetes.io/limit-connections: "1"
  name: ingress-with-auth
  namespace: study-ingress
spec:
  ingressClassName: nginx # for k8s >= 1.22+
  rules:
  - host: auth.test.com
    http:
      paths:
      - backend:
          service:
            name: nginx
            port:
              number: 80
        path: /
        pathType: ImplementationSpecific

再次使用ab测试,Failed为67:

[root@k8s-master01 5.10]# ab -c 10 -n 100 http://auth.test.com/ | grep requests:
Complete requests: 100
Failed requests: 67

还有很多其它方面的限制,常用的配置如下:

#限制每秒的连接,单个IP:
nginx.ingress.kubernetes.io/limit-rps
#限制每分钟的连接,单个IP:
nginx.ingress.kubernetes.io/limit-rpm
#限制客户端每秒传输的字节数,单位为K,需要开启proxy-buffering:
nginx.ingress.kubernetes.io/limit-rate
# 速率限制白名单
nginx.ingress.kubernetes.io/limit-whitelist

(十一) 使用Nginx实现灰度/金丝雀发布

1.创建v1版本

首先创建模拟Production(生产)环境的Namespace和服务:

# kubectl create ns production
namespace/production created
# kubectl create deploy canary-v1 --image=registry.cn-beijing.aliyuncs.com/dotbalo/canary:v1 -n production
# kubectl expose deploy canary-v1 --port 8080 -n production
# kubectl create ingress canary-v1 --rule=canary.com/*=canary-v1:8080 -n production

使用浏览器访问该服务,可以看到Canary v1的页面:


2.创建v2版本

接下来创建v2版本,充当灰度环境:

# kubectl create ns canary
namespace/canary created

创建v2版本的应用和Service:

# kubectl create deploy canary-v2 --image=registry.cn-beijing.aliyuncs.com/dotbalo/canary:v2 -n canary
# kubectl expose deploy canary-v2 --port 8080 -n canary

待程序启动完成后,通过Service访问该服务,会返回Canary v2:

# kubectl get svc -n canary
NAME        TYPE        CLUSTER-IP        EXTERNAL-IP   PORT(S)    AGE
canary-v2   ClusterIP   192.168.181.120   <none>        8080/TCP   89s
# curl 192.168.181.120:8080
<h1>Canary v2</h1>

接下来通过Ingress控制流量。

3.Canary版本切入部分流量

创建v2版本的Ingress时,需要添加两个注释,一个是nginx.ingress.kubernetes.io/canary,表明是灰度环境,nginx.ingress.kubernetes.io/canary-weight表明切多少流量到该环境,本示例为10%:

# vim canary-v2.yaml 
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    nginx.ingress.kubernetes.io/canary: "true"
    nginx.ingress.kubernetes.io/canary-weight: "10"
  name: canary-v2
  namespace: canary
spec:
  ingressClassName: nginx # for k8s >=1.22+
  rules:
  - host: canary.com
    http:
      paths:
      - backend:
          service:
            name: canary-v2
            port:
              number: 8080
        path: /
        pathType: ImplementationSpecific

此时通过nginx.ingress.kubernetes.io/canary-weight: "10"设置的权重是10,即v1:v2为9:1。

4.测试灰度发布

接下来使用Ruby脚本进行测试,此脚本会输出v1和v2的访问次数比值:

# vim  test-canary.rb 
counts = Hash.new(0)

100.times do
  output = `curl -s canary.com | grep 'Canary' | awk '{print $2}' | awk -F"<" '{print $1}'`
  counts[output.strip.split.last] += 1
end

puts counts

安装ruby并测试

# yum install ruby -y
# ruby test-canary.rb 
{"v1"=>90, "v2"=>10}
# ruby test-canary.rb 
{"v1"=>92, "v2"=>8}
# ruby test-canary.rb  
{"v1"=>91, "v2"=>9}

(十二) 环境清理

测试无误后,可以清理之前的学习数据:

# kubectl delete deploy,svc,ingress -n production --all
deployment.apps "canary-v1" deleted
service "canary-v1" deleted
ingress.networking.k8s.io "canary-v1" deleted
# kubectl delete deploy,svc,ingress -n canary --all
deployment.apps "canary-v2" deleted
service "canary-v2" deleted
ingress.networking.k8s.io "canary-v2" deleted
# kubectl delete deploy,svc,ingress -n study-ingress --all
deployment.apps "err-page" deleted
deployment.apps "laptop" deleted
deployment.apps "nginx" deleted
deployment.apps "phone" deleted
service "err-page" deleted
service "laptop" deleted
service "nginx" deleted
service "phone" deleted
ingress.networking.k8s.io "ingress-with-auth" deleted
ingress.networking.k8s.io "laptop" deleted
ingress.networking.k8s.io "nginx-ingress" deleted
ingress.networking.k8s.io "phone" deleted
# kubectl delete ns study-ingress production canary
namespace "study-ingress" deleted
namespace "production" deleted
namespace "canary" deleted
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