k8s ingress 控制器traefik
ingress 介绍
ingress 对外暴露集群http 和https 服务,之前k8s 是用iptables 的 ,不推荐,推荐用ipvs 模式。
ingress 是基于域名和url 路径把用户请求转发到指定service 资源的规则。
ingress 控制器能够将ingress 资源监听某套接字,然后根据ingress 规则匹配机制路由调度流量的组件。
ingress 实际上就个简化版的nginx + 一段go 脚本而已。
traefik 是 ingress 控制器的一种,还有nginx haproxy 也可以做 ingress 控制器。
traefik 介绍
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
traefik 部署
docker pull traefik:v1.7.2-alpine
准备资源配置清单:
yaml 文件参考:
https://github.com/containous/traefik/tree/v1.7/examples/k8s ,我用了daemonset 方式部署。
cd /data/k8s-yaml/traefik
cat > rbac.yaml <<EOF
apiVersion: v1
kind: ServiceAccount
metadata:
name: traefik-ingress-controller
namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
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
EOF
cat > ds.yaml<<EOF
apiVersion: extensions/v1beta1
kind: DaemonSet
metadata:
name: traefik-ingress
namespace: kube-system
labels:
k8s-app: traefik-ingress
spec:
template:
metadata:
labels:
k8s-app: traefik-ingress
name: traefik-ingress
spec:
serviceAccountName: traefik-ingress-controller
terminationGracePeriodSeconds: 60
containers:
- image: traefik:v1.7.2-alpine #刚拉取的镜像
name: traefik-ingress
ports:
- name: controller
containerPort: 80 #把容器的80 端口调度到node 81 端口,81就是ingress controller 端口。
hostPort: 81
- name: admin-web
containerPort: 8080
securityContext:
capabilities:
drop:
- ALL
add:
- NET_BIND_SERVICE
args:
- --api
- --kubernetes
- --logLevel=INFO
- --insecureskipverify=true
- --kubernetes.endpoint=https://10.4.7.10:7443
- --accesslog
- --accesslog.filepath=/var/log/traefik_access.log
- --traefiklog
- --traefiklog.filepath=/var/log/traefik.log
- --metrics.prometheus
EOF
cat >svc.yaml<<EOF
kind: Service
apiVersion: v1
metadata:
name: traefik-ingress-service
namespace: kube-system
spec:
selector:
k8s-app: traefik-ingress
ports:
- protocol: TCP
port: 80
name: controller
- protocol: TCP
port: 8080
name: admin-web
EOF
vim ingress.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: traefik-web-ui
namespace: kube-system
annotations:
kubernetes.io/ingress.class: traefik
spec:
rules:
- host: traefik.od.com
http:
paths:
- path: /
backend:
serviceName: traefik-ingress-service
servicePort: 8080
在7.21 上
kubectl apply -f http://k8s-yaml.od.com/traefik/rbac.yaml
kubectl apply -f http://k8s-yaml.od.com/traefik/ds.yaml
kubectl apply -f http://k8s-yaml.od.com/traefik/svc.yaml
kubectl apply -f http://k8s-yaml.od.com/traefik/ingress.yaml
kubectl get pods -n kube-system #检查
同时增加dns A 记录 traefik A 10.4.7.10
配置nginx 反向代理
在7.11 和7.12 上都要做
vim /etc/nginx/conf.d/od.com.conf upstream default_backend_traefik { server 10.4.7.21:81 max_fails=3 fail_timeout=10s; server 10.4.7.22:81 max_fails=3 fail_timeout=10s; } server { server_name *.od.com; #用泛域名匹配,这样新增了二级域名nginx配置不用加了 location / { proxy_pass http://default_backend_traefik; proxy_set_header Host $http_host; proxy_set_header x-forwarded-for $proxy_add_x_forwarded_for; } }
测试: 浏览器访问 http://traefik.od.com/dashboard/