k8s学习: Ingress Nginx

官网仓库：ingress-nginx仓库

从以上仓库点击 Getting Started 就到了安装上文档
NGINX Ingress Controller 安装文档

官网下载下来的 deploy 文件中，ingress 都是 LoadBalance
所以，学习环境和测试环境最好先去配置为支持 LoadBalance 的

前车之鉴：
本人之前着急进行下去没改成 NodePort 方式，（否则 controller 会一直 Pending ）然后，各种端口转来转去的，非常混乱，所以，回头配置了 MetalLB 之后，重新走了一遍！

k8s学习: 使用 MetalLB 给测试环境配置LoadBalancer 服务

1、下载 deploy 文件，并替换被墙的 image

按照 kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v1.1.0/deploy/static/provider/cloud/deploy.yaml

这里最新版本时 v1.1.0 ，所以，先下载 deploy 文件

wget https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v1.0.5/deploy/static/provider/cloud/deploy.yaml --no-check-certificate

里面镜像被墙，所以，通过 docker search 之后，只好降级到 v1.0.5

wget https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v1.0.5/deploy/static/provider/cloud/deploy.yaml --no-check-certificate

替换 image

vim deploy.yaml

查找可以替换的 images，有以下 3 处，共 2 个 image 需要替换

docker search controller:v1.0.5

 NAME                                    DESCRIPTION                                     STARS     OFFICIAL   AUTOMATEDxyz349925756/ingress-nginx-controller   k8s.gcr.io/ingress-nginx/controller:v1.0.5      0                    v5cn/controller                         sync k8s.gcr.io/ingress-nginx/controller:v1.…   0

docker search kube-webhook-certgen

 ...lianyuxue1020/kube-webhook-certgen   new pull lianyuxue1020/kube-webhook-certgen:…   0   ...

分别替换以上找到的 image

332 行

 image: v5cn/controller:v1.0.5 # xyz349925756/ingress-nginx-controller:v1.0.5 # registry.aliyuncs.com/google_containers/ingress-nginx/controller:v1.0.5@sha256:55a1fcda5b7657c372515    fe402c3e39ad93aa59f6e4378e82acd99912fe6028d

614 行

  image: lianyuxue1020/kube-webhook-certgen:v1.1.1 # registry.aliyuncs.com/google_containers/ingress-nginx/kube-webhook-certgen:v1.1.1@sha256:64d8c73dca984af206adf9d6d7e46aa550362b1    d7a01f3a0a91b20cc6786866

664 行

  image: lianyuxue1020/kube-webhook-certgen:v1.1.1 # registry.aliyuncs.com/google_containers/ingress-nginx/kube-webhook-certgen:v1.1.1@sha256:64d8c73dca984af206adf9d6d7e46aa550362b1    d7a01f3a0a91b20cc67868660

另外增加了 node 节点地址作为 externalIPs
这个不是必须的！只是之前使用 NodePort 方式时留下的

这个在文档 Bare-metal considerations 的 one could edit the ingress-nginx Service and add the following field to the object spec 这里的 Example
暂时没有太明白用途

   externalIPs:# - 192.168.1.188- 192.168.1.185- 192.168.1.186-

kubectl apply -f deploy.yaml

确认 ingress-nginx-controller
kubectl get pods --namespace=ingress-nginx

 NAME                                        READY   STATUS      RESTARTS        AGEingress-nginx-admission-create--1-cb45t     0/1     Completed   0               4h13mingress-nginx-admission-patch--1-dbnm8      0/1     Completed   1               4h13mingress-nginx-controller-557c5d96d6-lrj85   1/1     Running     1 (4h12m ago)   4h13m

2、 local 测试

按照文档中 Local testing

创建一个简单的 httpd 网站和服务

kubectl create deployment demo --image=httpd --port=80

kubectl expose deployment demo
创建一个 ingress 资源

kubectl create ingress demo-localhost --class=nginx
–rule=demo.localdev.me/*=demo:80
端口转发：转发 ingress controller 的 80 端口，到localhost 的 8080 端口

kubectl port-forward --namespace=ingress-nginx service/ingress-nginx-controller 8080:80
查询 ingress
kubectl get ingress

NAME CLASS HOSTS ADDRESS PORTS AGE

demo-localhost nginx demo.localdev.me 192.168.1.185,192.168.1.186,192.168.1.241 80 4h14m
curl 验证

无需 localhost 模拟DNS 域名 demo.localdev.me，因为 kubectl port-forward 中按照 sevice 名称就可以找到 demo.localdev.me 对应的 Cluster 地址，并转发到 local 地址

curl http://demo.localdev.me:8080/ 和 curl 127.0.0.1:8080 是一样的

curl http://demo.localdev.me:8080/
```
 <html><body><h1>It works!</h1></body></html>
```

3、在线测试

按照文档中 Online testing
注意这里写着

It will be the EXTERNAL-IP field. If that field shows , this means that your Kubernetes cluster wasn’t able to provision the load balancer (generally, this is because it doesn’t support services of type LoadBalancer).

意思是如果环境不支持 LoadBalancer ，这个服务会一直 Pending

创建一个 ingress ， host 设置为 www.demo.io

kubectl create ingress demo --class=nginx
–rule=“www.demo.io/*=demo:80”

查询 ingress 资源，现在有 2 个 ingress 了

kubectl get ingress

 NAME             CLASS   HOSTS              ADDRESS                                     PORTS   AGEdemo             nginx   www.demo.io        192.168.1.185,192.168.1.186,192.168.1.241   80      4h11mdemo-localhost   nginx   demo.localdev.me   192.168.1.185,192.168.1.186,192.168.1.241   80      4h14m

local 模拟 DNS
模拟域名 www.demo.io 指向 ingress 的 ADDRESS （192.168.1.241），demo 服务地址是 ClusterIP ，不能给 Cluster 之外使用

vim /etc/hosts

 127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4::1         localhost localhost.localdomain localhost6 localhost6.localdomain6# 127.0.0.1 centos7-188192.168.1.189 centos7-189192.168.1.188 centos7-188192.168.1.186 centos7-186192.168.1.185 centos7-185# ingress192.168.1.185 www.demo.io192.168.1.186 www.demo.io192.168.1.241 www.demo.io192.168.1.186  www.demo1.io192.168.1.186  www.demo1.io192.168.1.241  www.demo1.io192.168.1.240  www.demo1.io

查询服务 IP
查询 ingress-nginx-controller 服务的 IP

kubectl get service ingress-nginx-controller --namespace=ingress-nginx

 NAME                       TYPE           CLUSTER-IP       EXTERNAL-IP                                 PORT(S)                      AGEingress-nginx-controller   LoadBalancer   10.106.206.189   192.168.1.241,192.168.1.185,192.168.1.186   80:32423/TCP,443:30832/TCP   4h23m

查询 demo 服务的 IP

kubectl get svc

 NAME         TYPE           CLUSTER-IP       EXTERNAL-IP     PORT(S)        AGEdemo         ClusterIP      10.109.183.133   <none>          80/TCP         4h33m...

curl 验证
因为 demo 服务的 IP 是 ClusterIP ，他没有EXTERNAL-IP ，所以
curl http://www.demo1.io/. 可以，但是 curl 192.168.1.241 不可以

curl http://www.demo.io/.
```
 <html><body><h1>It works!</h1></body></html>
```

4、测试之前 LoadBalancer 的 nginx 服务

前面 k8s学习: k8s学习: 使用 MetalLB 给测试环境配置LoadBalancer 服务的时候，创建过一个 nginx 例子，现在拿来测试一下

创建一个 ingress 资源： demo1，域名：www.demo1.io

kubectl create ingress demo1 --class=nginx --rule=“www.demo1.io/*=demo1:80”

现在有 3 个 ingress 资源了！

kubectl get ingress

 NAME             CLASS   HOSTS              ADDRESS                                     PORTS   AGEdemo             nginx   www.demo.io        192.168.1.185,192.168.1.186,192.168.1.241   80      4h11mdemo-localhost   nginx   demo.localdev.me   192.168.1.185,192.168.1.186,192.168.1.241   80      4h14mdemo1            nginx   www.demo1.io       192.168.1.185,192.168.1.186,192.168.1.241   80      3h50m

查询服务的 IP

kubectl get svc

 NAME         TYPE           CLUSTER-IP       EXTERNAL-IP     PORT(S)        AGEdemo         ClusterIP      10.109.183.133   <none>          80/TCP         4h33mdemo1        LoadBalancer   10.103.89.77     192.168.1.240   80:31590/TCP   4h51mkubernetes   ClusterIP      10.96.0.1        <none>          443/TCP        5h29m

修改 /etc/hosts ，加上 www.demo1.io 解析

curl 验证

因为 demo1 的 IP 是 LoadBalancer ，他拥有一个 EXTERNAL-IP
所以，curl http://www.demo1.io/. 和 curl 192.168.1.240 是一样的

curl 192.168.1.240
curl http://www.demo1.io/.

 <!DOCTYPE html><html><head><title>Welcome to nginx!</title><style>html { color-scheme: light dark; }body { width: 35em; margin: 0 auto;font-family: Tahoma, Verdana, Arial, sans-serif; }</style></head><body><h1>Welcome to nginx!</h1><p>If you see this page, the nginx web server is successfully installed andworking. Further configuration is required.</p><p>For online documentation and support please refer to<a href="http://nginx.org/">nginx.org</a>.<br/>Commercial support is available at<a href="http://nginx.com/">nginx.com</a>.</p><p><em>Thank you for using nginx.</em></p></body></html>

5、删除 deploy 中增加的 node 节点地址作为 externalIPs ，对比一下

kubectl get service ingress-nginx-controller --namespace=ingress-nginx

NAME                       TYPE           CLUSTER-IP      EXTERNAL-IP     PORT(S)                      AGE
ingress-nginx-controller   LoadBalancer   10.105.20.144   192.168.1.241   80:31782/TCP,443:30630/TCP   11s

kubectl get ingress

NAME             CLASS   HOSTS              ADDRESS         PORTS   AGE
demo             nginx   www.demo.io        192.168.1.241   80      5h11m
demo-localhost   nginx   demo.localdev.me   192.168.1.241   80      5h14m
demo1            nginx   www.demo1.io       192.168.1.241   80      4h50m

kubectl get svc

NAME         TYPE           CLUSTER-IP       EXTERNAL-IP     PORT(S)        AGE
demo         ClusterIP      10.109.183.133   <none>          80/TCP         5h16m
demo1        LoadBalancer   10.103.89.77     192.168.1.240   80:31590/TCP   5h34m
kubernetes   ClusterIP      10.96.0.1        <none>          443/TCP        6h12m

这样子比较纯粹！不会再 redirest 到 node 地址，只有 LoadBalancer 的虚拟 IP ！