一、如何实现外界能访问
外界访问不了
1、启动svc
[root@k8s-master ~]# cat myweb-svc.yaml
apiVersion: v1
kind: Service
metadata:
name: nginx
spec:
type: NodePort
ports:
- port: 80
nodePort: 30001
selector:
app: myweb
[root@k8s-master ~]# kubectl create -f myweb-svc.yaml
service "nginx" created
2、查看svc状态
[root@k8s-master ~]# kubectl get all
NAME DESIRED CURRENT READY AGE
rc/myweb 3 3 3 19m NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
svc/kubernetes 10.254.0.1 <none> 443/TCP 22h
svc/nginx 10.254.205.175 <nodes> 80:30001/TCP 27s NAME READY STATUS RESTARTS AGE
po/myweb-7m76h 1/1 Running 0 18m
po/myweb-kzq8c 1/1 Running 0 18m
po/myweb-mnf7x 1/1 Running 0 18m
3、被外界访问原理图
二、为什么是30001？
1、修改为3000看看是否正常？
[root@k8s-master ~]# vim myweb-svc.yaml
更改端口为：3000
[root@k8s-master ~]# kubectl delete svc/nginx
service "nginx" deleted
[root@k8s-master ~]# kubectl create -f myweb-svc.yaml
The Service "nginx" is invalid: spec.ports[0].nodePort: Invalid value: 3000:
provided port is not in the valid range. The range of valid ports is 30000-32767
2、端口更改为30001
[root@k8s-master ~]# vim myweb-svc.yaml
更改端口为：30001
[root@k8s-master ~]# kubectl create -f myweb-svc.yaml
service "nginx" created
[root@k8s-master ~]# kubectl get all
NAME DESIRED CURRENT READY AGE
rc/myweb 3 3 3 25m NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
svc/kubernetes 10.254.0.1 <none> 443/TCP 22h
svc/nginx 10.254.145.15 <nodes> 80:30027/TCP 8s NAME READY STATUS RESTARTS AGE
po/myweb-7m76h 1/1 Running 0 24m
po/myweb-kzq8c 1/1 Running 0 24m
po/myweb-mnf7x 1/1 Running 0 25m
默认不填写，自动分配30000-32767内任意一端口
三、自动加载到负载均衡里面
1、修改svc副本数为1
[root@k8s-master ~]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE
myweb-7m76h 1/1 Running 0 26m 172.16.10.2 k8s-node1
myweb-kzq8c 1/1 Running 0 26m 172.16.48.4 k8s-node2
myweb-mnf7x 1/1 Running 0 26m 172.16.48.2 k8s-node2 [root@k8s-master ~]# kubectl edit rc myweb
replicas: 1
replicationcontroller "myweb" edited [root@k8s-master ~]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE
myweb-mnf7x 1/1 Running 0 28m 172.16.48.2 k8s-node2
[root@k8s-master ~]# kubectl describe svc nginx
Name: nginx
Namespace: default
Labels: <none>
Selector: app=myweb
Type: NodePort
IP: 10.254.145.15
Port: <unset> 80/TCP
NodePort: <unset> 30027/TCP
Endpoints: 172.16.48.2:80
Session Affinity: None
No events.
2、修改svc副本数为5
[root@k8s-master ~]# kubectl edit rc myweb
replicas: 5
replicationcontroller "myweb" edited
[root@k8s-master ~]# kubectl describe svc nginx
Name: nginx
Namespace: default
Labels: <none>
Selector: app=myweb
Type: NodePort
IP: 10.254.145.15
Port: <unset> 80/TCP
NodePort: <unset> 30027/TCP
Endpoints: 172.16.10.2:80,172.16.10.3:80,172.16.48.2:80 + 1 more...
Session Affinity: None
No events.
[root@k8s-master ~]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE
myweb-415zs 1/1 Running 0 9s 172.16.48.3 k8s-node2
myweb-7bw5f 1/1 Running 0 9s 172.16.10.3 k8s-node1
myweb-7kzh2 1/1 Running 0 9s 172.16.48.4 k8s-node2
myweb-j45xb 1/1 Running 0 9s 172.16.10.2 k8s-node1
myweb-mnf7x 1/1 Running 0 30m 172.16.48.2 k8s-node2
四、上网测试截图
1、node1 web截图
2、node2 web截图