k8s 的ingress+traefik原理细说
ingress 本质上就是一个nginx或者traefik 代理。 他将用户的请求该域名的请求转发到后端的service。
做LB 实际上是kubernets的Service。
部署原理
daemonset 方式部署 traffic或者nginx,让其监听在80端口和443端口，默认是随机端口，通过hostport可以指定端口
K8S 中必须 Create Role Based Access 蛋疼，
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: traefik-ingress-controller
rules:
- apiGroups:
- ""
resources:
- services
- endpoints
- secrets
verbs:
- get
- list
- watch
- apiGroups:
- extensions
resources:
- ingresses
verbs:
- get
- list
- watch
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: traefik-ingress-controller
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: traefik-ingress-controller
subjects:
- kind: ServiceAccount
name: traefik-ingress-controller
namespace: kube-system
daemonset 例子
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: traefik-ingress-controller
namespace: kube-system
---
kind: Deployment
apiVersion: extensions/v1beta1
metadata:
name: traefik-ingress-controller
namespace: kube-system
labels:
k8s-app: traefik-ingress-lb
spec:
replicas: 1
selector:
matchLabels:
k8s-app: traefik-ingress-lb
template:
metadata:
labels:
k8s-app: traefik-ingress-lb
name: traefik-ingress-lb
spec:
serviceAccountName: traefik-ingress-controller
terminationGracePeriodSeconds: 60
containers:
- image: traefik
name: traefik-ingress-lb
args:
- --web
- --kubernetes
---
kind: Service
apiVersion: v1
metadata:
name: traefik-ingress-service
namespace: kube-system
spec:
selector:
k8s-app: traefik-ingress-lb
ports:
- protocol: TCP
port: 80
name: web
- protocol: TCP
port: 8080
name: admin
type: NodePort
创建DaemonSet
Kubectl create -f ds.yaml
kubectl --namespace=kube-system get pods
NAME READY STATUS RESTARTS AGE
kube-addon-manager-minikubevm 1/1 Running 0 4h
kubernetes-dashboard-s8krj 1/1 Running 0 4h
traefik-ingress-controller-678226159-eqseo 1/1 Running 0 7m
构建UI
apiVersion: v1
kind: Service
metadata:
name: traefik-web-ui
namespace: kube-system
spec:
selector:
k8s-app: traefik-ingress-lb
ports:
- port: 80
targetPort: 8080
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: traefik-web-ui
namespace: kube-system
annotations:
kubernetes.io/ingress.class: traefik
spec:
rules:
- host: traefik-ui.minikube
http:
paths:
- backend:
serviceName: traefik-web-ui
servicePort: 80
转发规则
---
kind: Deployment
apiVersion: extensions/v1beta1
metadata:
name: stilton
labels:
app: cheese
cheese: stilton
spec:
replicas: 2
selector:
matchLabels:
app: cheese
task: stilton
template:
metadata:
labels:
app: cheese
task: stilton
version: v0.0.1
spec:
containers:
- name: cheese
image: errm/cheese:stilton
ports:
- containerPort: 80
---
kind: Deployment
apiVersion: extensions/v1beta1
metadata:
name: cheddar
labels:
app: cheese
cheese: cheddar
spec:
replicas: 2
selector:
matchLabels:
app: cheese
task: cheddar
template:
metadata:
labels:
app: cheese
task: cheddar
version: v0.0.1
spec:
containers:
- name: cheese
image: errm/cheese:cheddar
ports:
- containerPort: 80
---
kind: Deployment
apiVersion: extensions/v1beta1
metadata:
name: wensleydale
labels:
app: cheese
cheese: wensleydale
spec:
replicas: 2
selector:
matchLabels:
app: cheese
task: wensleydale
template:
metadata:
labels:
app: cheese
task: wensleydale
version: v0.0.1
spec:
containers:
- name: cheese
image: errm/cheese:wensleydale
ports:
- containerPort: 80
基于https
沿用上文 的Role Based Access(RBAC)
首先得厘清几个概念
-
Secret, 保存密钥文件， 我们这次把pem，key等文件通过这种方式传入pod 内
# 创建一个名为 ak-cert secret文件 kubectl create secret generic mjb-cert --from-file=/server.pem --from-file=server.key
-
ConfigMap,配置文件，创建一个配置文件,和secret一样， 通过volumes方式挂载到容器内
cat traefik.toml defaultEntryPoints = ["http","https"] [entryPoints] [entryPoints.http] address = ":80" [entryPoints.http.redirect] entryPoint = "https" [entryPoints.https] address = ":443" [entryPoints.https.tls] [[entryPoints.https.tls.certificates]] CertFile = "/mjb/server.pem" KeyFile = "/mjb/server.key"
-
挂载方法
#定义volumes volumes: - name: mjb secret: secretName: ak-cert - name: config configMap: name: traefik-conf containers: - image: traefik name: traefik-ingress-lb ## 挂载 volumeMounts: - mountPath: "/mjb" name: "mjb" - mountPath: "/config" name: "config" -
部署daemonset
[root@master https]# cat dae.yaml --- apiVersion: v1 kind: ServiceAccount metadata: name: traefik-ingress-controller namespace: kube-system --- kind: DaemonSet apiVersion: extensions/v1beta1 metadata: name: traefik-ingress-controller namespace: kube-system labels: k8s-app: traefik-ingress-lb spec: template: metadata: labels: k8s-app: traefik-ingress-lb name: traefik-ingress-lb spec: serviceAccountName: traefik-ingress-controller terminationGracePeriodSeconds: 60 volumes: - name: mjb secret: secretName: mjb-cert - name: config configMap: name: traefik-conf containers: - image: traefik name: traefik-ingress-lb volumeMounts: - mountPath: "/mjb" name: "mjb" - mountPath: "/config" name: "config" ports: - name: web containerPort: 80 hostPort: 80 - name: https containerPort: 443 hostPort: 443 - name: admin containerPort: 8580 args: - --web - --kubernetes - --web.address=:8580 - --configfile=/config/traefik.toml --- kind: Service apiVersion: v1 metadata: name: traefik namespace: kube-system spec: selector: k8s-app: traefik-ingress-lb ports: - protocol: TCP port: 80 name: http - protocol: TCP port: 443 name: https - protocol: TCP port: 8580 name: admin type: NodePort
-
部署基于https的UI
apiVersion: v1 kind: Service metadata: name: traefik-web-ui namespace: kube-system spec: selector: k8s-app: traefik-ingress-lb ports: - port: 80 targetPort: 8580 --- apiVersion: extensions/v1beta1 kind: Ingress metadata: name: traefik-web-ui namespace: kube-system annotations: kubernetes.io/ingress.class: traefik spec: tls: - secretName: traefik-cert rules: - host: ui.domain.com http: paths: - backend: serviceName: traefik-web-ui servicePort: 80访问测试 ui.domain.com, 对了上文的证书需自己准备，如果没有可以生成
openssl req -newkey rsa:2048 -nodes -keyout domain.com.key -x509 -days 365 -out domain.com.crt
