image.png
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：
16、服务暴露 - 图2
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。

1、服务暴露之nodePort型Service

使用NodePort型Service只能使用iptables，需要修改kube-porxy.sh规则
vi /opt/kubernetes/server/bin/kube-proxy.sh
输入：
#!/bin/sh
./kube-proxy \
—cluster-cidr 172.7.0.0/16 \
—hostname-override hdss7-21.host.com \
—proxy-mode=iptables \
—ipvs-scheduler=rr \
—kubeconfig ./conf/kube-proxy.kubeconfig

注意iptables的调度方式只能是rr（时间片轮转）

ps aux | grep kube-proxy
杀死kube-proxy进程kill +进程Id 然后通过supervisor自动拉起更新

查看原有ipvs路由规则：ipvsadm -Ln
image.png

ipvsadn -D -t 192.168.0.1:443
ipvsadn -D -t 192.168.0.2:53
ipvsadn -D -t 192.168.0.2:9153
ipvsadn -D -t 192.168.13.234:80
ipvsadn -D -u 192.168.0.2:53
其中-D表示删除，-t表示tcp规则，-u表示udp规则

vi nginx-dp-svc.yaml
输入：
apiVersion: v1
kind: Service
metadata:
labels:
app: nginx-ds
name: nginx-ds
namespace: default
spec:
ports:
-port: 80
protocol: TCP
nodePort: 8000
selector:
app: nginx-ds
sessionAffinity: None
type: NodePort

2、服务暴露之ingress

下面我们部署traefik：GITHUB官方地址 在hdss7-200上执行：

1、下载镜像

cd /data/k8s-yaml/traefik/

docker pull traefik:v1.7.2-alpine
docker tag add5fac61ae5 harbor.jack.com/public/traefik:v1.7.2
docker push harbor.jack.com/public/traefik:v1.7.2

2、创建资源配置清单

cd /data/k8s-yaml/traefik/

vi rbac.yaml

输入：
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

vi ds.yaml

输入：
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.jack.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

vi svc.yaml

输入：
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

vi ingress.yaml

输入：
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: traefik-web-ui
namespace: kube-system
annotations:
kubernetes.io/ingress.class: traefik
spec:
rules:
- host: traefik.jack.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.jack.com/traefik/rbac.yaml
kubectl create -f http://k8s-yaml.jack.com/traefik/ds.yaml
kubectl create -f http://k8s-yaml.jack.com/traefik/svc.yaml
kubectl create -f http://k8s-yaml.jack.com/traefik/ingress.yaml

kubectl get pods -n kube-system
image.png

kubectl describe pods traefik-ingress-j796r
image.png

3、配置nginx解析：hdss7-11,hdss7-12

vi /etc/nginx/conf.d/jack.com.conf
输入：
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 *.jack.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;
}
}

执行：nginx -t
nginx -s reload

4、在hdss7-11上添加域名解析：在ingress.yaml中的host值

vi /var/named/jack.com.zone
输入：
$ORIGIN jack.com.
$TTL 600 ; 10 minutes
@ IN SOA dns.jack.com. dnsadmin.jack.com. (
2019061804 ; serial
10800 ; refresh (3 hours)
900 ; retry (15 minutes)
604800 ; expire (1 week)
86400 ; minimum (1 day)
)
NS dns.jack.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.jack.com #我们的宿主机的虚拟网卡指定了bind域名解析服务器