kubernetes进阶（四）服务暴露-ingress控制器之traefik
上一章我们测试了在集群内部解析service名称，
下面我们测试在集群外部解析：
根本解析不到，因为我们外部用的dns是10.4.7.11，也就是我们的自建bind dns，这个DNS服务器上也没有响应的搜索域。
如何能让集群外部访问nginx-dp？
这里有两种服务暴露方式：修改工作模式，在kube-proxy中修改，并重启
1、使用nodeport方式，但是这种方式不能使用ipvs，只能使用iptables，iptables只能使用rr调度方式。原理相当于端口映射，将容器内的端口映射到宿主机上的某个端口。
2、使用ingress，但是只能工作在七层网络下，建议暴露http, https可以使用前端nginx来做证书方面的卸载 ---推荐使用
Ingress是基于域名和URL路径，将用户的请求转发至特定的service资源。
下面我们部署traefik：GITHUB官方地址 在hdss7-200上执行：
下载镜像：
# docker pull traefik:v1.7.2-alpine
# docker tag add5fac61ae5 harbor.od.com/public/traefik:v1.7.2
# docker push harbor.od.com/public/traefik:v1.7.
创建资源配置清单：
1.rbac.yaml
# cd /data/k8s-yaml/traefik/
# vi rbac.yaml
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
2.ds.yaml
# vi ds.yaml
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: harbor.od.com/public/traefik:v1.7.2 name: traefik-ingress ports: - name: controller containerPort: 80 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
3.svc.yaml
# vi svc.yaml
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
4.ingress.yaml
# vi 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
然后到node节点上创建资源：
# kubectl create -f http://k8s-yaml.od.com/traefik/rbac.yaml # kubectl create -f http://k8s-yaml.od.com/traefik/ds.yaml # kubectl create -f http://k8s-yaml.od.com/traefik/svc.yaml # kubectl create -f http://k8s-yaml.od.com/traefik/ingress.yaml
配置nginx解析：hdss7-11,hdss7-12
# vi /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; location / { proxy_pass http://default_backend_traefik; proxy_set_header Host $http_host; proxy_set_header x-forwarded-for $proxy_add_x_forwarded_for; } }
在hdss7-11上添加域名解析：在ingress.yaml中的host值：
# vi /var/named/od.com.zone
在最后加上traefik的域名解析：
$ORIGIN od.com. $TTL 600 ; 10 minutes @ IN SOA dns.od.com. dnsadmin.od.com. ( 2019061804 ; serial 10800 ; refresh (3 hours) 900 ; retry (15 minutes) 604800 ; expire (1 week) 86400 ; minimum (1 day) ) NS dns.od.com. $TTL 60 ; 1 minute dns A 10.4.7.11 harbor A 10.4.7.200 k8s-yaml A 10.4.7.200 traefik A 10.4.7.10
# systemctl restart named
然后我们就可以在集群外，通过浏览器访问这个域名了：
http://traefik.od.com #我们的宿主机的虚拟网卡指定了bind域名解析服务器
