K8s-Traefik Ingress Controller

Traefik Ingress Controller

Traefik 是一个为了让部署微服务更加便捷而诞生的现代 HTTP 反向代理、负载均衡工具。traefik 本身设计的就能够实时跟 kubernetes api 交互，感知后端 service，pod 等的变化，自动更新配置并重载。

traefik 是一个前端负载均衡器，对于微服务架构尤其是 kubernetes 等编排工具具有良好的支持；

同 nginx 等相比，traefik 能够自动感知后端容器变化，从而实现自动服务发现。

traefik 部署在 k8s 上分为 daemonset 和 deployment 两种方式，各有优缺点：

daemonset 能确定有哪些 Node 在运行 traefik，所以可以确定的知道后端 ip，但是不能方便的伸缩。
deployment 可以更方便的伸缩，但是不能确定有哪些 Node 在运行 traefik 所以不能确定的知道后端 ip。

一般部署两种不同类型的 traefik:

面向内部（internal）服务的 traefik，建议可以使用 deployment 的方式。
面向外部（external）服务的 traefik，建议可以使用 daemonset 的方式。
1
2

建议使用 traffic-type 标签

traffic-type: external
traffic-type: internal
1
2

traefik 相应地使用 labelSelector

traffic-type=internal
traffic-type=external
1
2

官方网址: https://docs.traefik.io/
下载源码：git clone https://github.com/containous/traefik.git
1
2

//部署 nginx-ingress-controller
1、获取配置文件

mkdir /opt/traefik
cd /opt/traefik
1
2

官方下载地址：

wget  https://raw.githubusercontent.com/containous/traefik/v1.7/examples/k8s/traefik-rbac.yaml
wget  https://raw.githubusercontent.com/containous/traefik/v1.7/examples/k8s/traefik-deployment.yaml
wget  https://raw.githubusercontent.com/containous/traefik/v1.7/examples/k8s/traefik-ds.yaml
wget  https://raw.githubusercontent.com/containous/traefik/v1.7/examples/k8s/ui.yaml
1
2
3
4

国内的 gitee：

wget  https://gitee.com/mirrors/traefik/raw/v1.7/examples/k8s/traefik-deployment.yaml
wget  https://gitee.com/mirrors/traefik/raw/v1.7/examples/k8s/traefik-rbac.yaml
wget  https://gitee.com/mirrors/traefik/raw/v1.7/examples/k8s/traefik-ds.yaml
wget  https://gitee.com/mirrors/traefik/raw/v1.7/examples/k8s/ui.yaml
1
2
3
4

2、依次执行
//启用RBAC

kubectl apply -f traefik-rbac.yaml
1

//部署 Traefik 到 Kubernetes 集群，为外部访问创建 NodePorts

kubectl apply -f traefik-deployment.yaml
1

//部署 Traefik Web UI

kubectl apply -f ui.yaml
1

//查看结果

kubectl get svc -o wide -n kube-system | grep traefik
traefik-ingress-service   NodePort    10.96.241.13   <none>        80:32383/TCP,8080:32133/TCP   103m   k8s-apptraefik-ingress-lb
traefik-web-ui            ClusterIP   10.96.67.119   <none>        80/TCP                        101m   k8s-apptraefik-ingress-lb
1
2
3

//访问 Traefik UI，浏览器访问 http://Nodeip:NodePort/dashboard/

http://192.168.80.14:32133/dashboard/
1

//Ingress HTTP 代理访问

cd /opt/ingress-nodeport
1

#创建 deployment、Service、Ingress Yaml 资源

vim ingress-nginx.yaml 
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-app
spec:
  replicas: 2
  selector:
    matchLabels:
      name: nginx
  template:
    metadata:
      labels:
        name: nginx
    spec:
      containers:
        - name: nginx
          image: nginx
          imagePullPolicy: IfNotPresent
          ports:
            - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: nginx-svc
spec:
  ports:
    - port: 80
      targetPort: 80
      protocol: TCP
  selector:
    name: nginx
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: nginx-test
spec:
  rules:
    - host: www.my.com
      http:
        paths:
        - path: /
          pathType: Prefix
          backend:
            service: 
              name: nginx-svc
              port:
                number: 80


kubectl apply -f ingress-nginx.yaml
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53

kubectl get svc,pods -o wide

NAME                 TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)   AGE   SELECTOR
service/kubernetes   ClusterIP   10.96.0.1      <none>        443/TCP   23d   <none>
service/nginx-svc    ClusterIP   10.96.89.181   <none>        80/TCP    88m   name=nginx

NAME                             READY   STATUS    RESTARTS   AGE   IP           NODE     NOMINATED NODE   READINESS GATES
pod/nginx-app-65d7b99f6b-nnw7q   1/1     Running   0          88m   10.244.2.4   node02   <none>           <none>
pod/nginx-app-65d7b99f6b-x47l8   1/1     Running   0          88m   10.244.1.5   node01   <none>           <none>
1
2
3
4
5
6
7
8
9

kubectl exec -it pod/nginx-app-65d7b99f6b-nnw7q bash
 # cd /usr/share/nginx/html/
 # echo 'this is web1' >> index.html 
1
2
3

kubectl exec -it pod/nginx-app-65d7b99f6b-x47l8 bash
 # cd /usr/share/nginx/html/
 # echo 'this is web2' >> index.html
1
2
3

#测试访问

curl 10.96.89.181
1

kubectl get svc -o wide -n kube-system | grep traefik
traefik-ingress-service   NodePort    10.96.241.13   <none>        80:32383/TCP,8080:32133/TCP   103m   k8s-apptraefik-ingress-lb
traefik-web-ui            ClusterIP   10.96.67.119   <none>        80/TCP                        101m   k8s-apptraefik-ingress-lb
1
2
3

#本地 host 添加域名解析

vim /etc/hosts
192.168.80.10 master
192.168.80.11 node01
192.168.80.12 node02
192.168.80.12 www.xiaoma.com www.my.com
1
2
3
4
5

#模拟外部访问

curl http://www.my.com:32383
1

#再刷新查看 Traefik UI 界面，会生成刚创建的集群信息

http://192.168.80.14:32133/dashboard/
1