前面的文章介绍了如何安装kubernetes集群,集群部署完毕之后就可以在上面部署服务了。服务部署完之后如何访问集群中的服务呢? 访问部署在kubernetes中的服务有两种情况,一种是在kubernetes集群内部访问,另一种是在集群外部访问服务。
Clusterip是集群内部的私有ip,在集群内部访问服务非常方便,直接通过service的Clusterip访问。如果安装了kube-dns可以使用serviceName的方式访问服务。
请看下面例子 创建一个nginx服务,名称是my-nginx
[root@vmnode1 ~]# cat my-nginx.yaml
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: my-nginx
spec:
replicas: 2
template:
metadata:
labels:
run: my-nginx
spec:
containers:
- name: my-nginx
image: nginx:1.7.9
ports:
- containerPort: 80
# 创建my-nginx
[root@vmnode1 ~]# kubectl create -f ./my-nginx.yaml
[root@vmnode1 ~]# kubectl expose deploy my-nginx
[root@vmnode1 ~]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.254.0.1 <none> 443/TCP 36d
my-nginx ClusterIP 10.254.180.15 <none> 80/TCP 6m
在集群中创建一个pod,通过ServiceName访问nginx服务
[root@vmnode1 ~]# kubectl run -it --image=radial/busyboxplus sh
##通过ServerName访问nginx
/ # curl http://my-nginx<!DOCTYPE html><html><head><title>Welcome to nginx!</title><style>
body { width: 35em; margin: 0 auto; font-family: Tahoma, Verdana, Arial, sans-serif; }</style></head><body><h1>Welcome to nginx!</h1><p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p><p>For online documentation and support please refer to<a href="http://nginx.org/">nginx.org</a>.<br/>Commercial support is available at<a href="http://nginx.com/">nginx.com</a>.</p><p><em>Thank you for using nginx.</em></p></body></html>
把service的port映射到每个节点内部指定port上,所有节点内部映射的port都一样。 看下面例子
#删除my-nginxkubectl delete svc/my-nginx
kubectl delete deploy/my-nginx123
修改my-nginx.yaml增加NodePort,在每个节点内部暴露30001端口
[root@vmnode1 ~]# cat my-nginx.yaml
apiVersion: extensions/v1beta1
kind: Deployment
metadata: name: my-nginx
spec:
replicas: 2
template:
metadata:
labels: run: my-nginx
spec:
containers:
- name: my-nginx
image: nginx:1.7.9
ports:
- containerPort: 80---apiVersion: v1
kind: Service
metadata: name: my-nginx
labels: run: my-nginx
spec:
type: NodePort
ports:
- port: 80
targetPort: 80
nodePort: 30001
selector: run: my-nginx
#创建my-nginx服务
kubectl create -f ./my-nginx.yaml
我的集群由四个几点构成 vmnode1 192.168.123.81 vmnode2 192.168.123.82 vmnode3 192.168.123.83 vmnode4 192.168.123.84
在集群之外,通过任何一个节点的ip+nodeport都可以访问集群中服务
[root@vmnode5 ~]# curl
[root@vmnode5 ~]# curl
[root@vmnode5 ~]# curl
[root@vmnode5 ~]# curl http://192.168.123.84:30001
使用NodeIp+Nodeport的方式实现,利用云平台提供的loadbalance服务,像aws、azure、openstack、gce都提供了loadbalance服务
这里不做介绍了
Ingress 使用开源的反向代理负载均衡器来实现对外暴漏服务,比如 Nginx、Apache、Haproxy等。Nginx Ingress 一般有三个组件组成:
下载地址 https://github.com/kubernetes/ingress-nginx/archive/nginx-0.11.0.tar.gz
ingress-nginx文件位于deploy目录下,各文件的作用:
修改with-rbac.yaml
apiVersion: extensions/v1beta1
kind: Daemonsetmetadata:
name: nginx-ingress-controller
namespace: ingress-nginx
spec:
selector:
matchLabels:
app: ingress-nginx
template:
metadata:
labels:
app: ingress-nginx
annotations:
prometheus.io/port: '10254'
prometheus.io/scrape: 'true'
spec:
serviceAccountName: nginx-ingress-serviceaccount
hostNetwork: true
containers:
- name: nginx-ingress-controller
image: quay.io/kubernetes-ingress-controller/nginx-ingress-controller:0.11.0
args:
- /nginx-ingress-controller
- --default-backend-service=$(POD_NAMESPACE)/default-http-backend
- --configmap=$(POD_NAMESPACE)/nginx-configuration
- --tcp-services-configmap=$(POD_NAMESPACE)/tcp-services
- --udp-services-configmap=$(POD_NAMESPACE)/udp-services
- --annotations-prefix=nginx.ingress.kubernetes.io
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
ports:
- name: http
containerPort: 80
- name: https
containerPort: 443
livenessProbe:
failureThreshold: 3
httpGet:
path: /healthz
port: 10254
scheme: HTTP
initialDelaySeconds: 10
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 1
readinessProbe:
failureThreshold: 3
httpGet:
path: /healthz
port: 10254
scheme: HTTP
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 1 nodeSelector:
custom/ingress-controller-ready: "true"
需要修改的地方:
为需要部署nginx-ingress-controller的节点设置lable
kubectl label nodes vmnode2 custom/ingress-controller-ready=true
kubectl label nodes vmnode3 custom/ingress-controller-ready=true
kubectl label nodes vmnode4 custom/ingress-controller-ready=true
加载yaml文件
kubectl create -f namespace.yaml
kubectl create -f default-backend.yaml
kubectl create -f configmap.yaml
kubectl create -f tcp-services-configmap.yaml
kubectl create -f udp-services-configmap.yaml
kubectl create -f rbac.yaml
kubectl create -f with-rbac.yaml
查看pod是否正常创建
##下载镜像可能会比较慢,等待一会所有pod都是Running状态,按Ctrl + c 退出
[root@vmnode1 deploy]# kubectl get pods --namespace=ingress-nginx --watch
NAME READY STATUS RESTARTS AGEdefault-
http-backend-6c59748b9b-hc8q9 1/1 Running 0 6m
nginx-ingress-controller-7fmlp 1/1 Running 1 13d
nginx-ingress-controller-j95fb 1/1 Running 1 13d
nginx-ingress-controller-ld2jw 1/1 Running 1 13d
测试ingress 创建一个apache的Service
[root@vmnode1 ~]# cat my-apache.yaml api
Version: extensions/v1beta1
kind: Deployment
metadata:
name: my-apache
spec:
replicas: 2
template:
metadata:
labels:
run: my-apache
spec:
containers:
- name: my-apache
image: httpd:2.4
ports:
- containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
name: my-apache
labels:
run: my-apache
spec:
type: NodePort
ports:
- port: 80
targetPort: 80
nodePort: 30002
selector:
run: my-apache
[root@vmnode1 ~]# kubectl create -f ./my-apache.yaml my-nginx
不用改,使用上面已经创建好的,如果没有自己创建一下
[root@vmnode1 ~]# cat my-nginx.yamlapi
Version: extensions/v1beta1
kind: Deployment
metadata:
name: my-nginx
spec:
replicas: 2
template:
metadata:
labels:
run: my-nginx
spec:
containers:
- name: my-nginx
image: nginx:1.7.9
ports:
- containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
name: my-nginx
labels:
run: my-nginx
spec:
type: NodePort
ports:
- port: 80
targetPort: 80
nodePort: 30001
selector:
run: my-nginx
现在集群中有两个服务,一个是my-apache,另一个是my-nginx
[root@vmnode1 ~]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.254.0.1 <none> 443/TCP 51d
my-apache NodePort 10.254.239.1 <none> 80:30002/TCP 8m
my-nginx NodePort 10.254.66.98 <none> 80:30001/TCP 14d
配置ingress转发文件
[root@vmnode1 ~]# vi test-ingress.yaml
apiVersion: extensions/v1beta1
kind: Ingressmetadata:
name: test-ingress
namespace: defaultspec:
rules:
- host: test.apache.ingress
http:
paths:
- path: /
backend:
serviceName: my-apache
servicePort: 80
- host: test.nginx.ingress
http:
paths:
- path: /
backend:
serviceName: my-nginx
servicePort: 80
host: 对应的域名 path: url上下文 backend:后向转发 到对应的 serviceName: servicePort:
[root@vmnode1 ~]# kubectl apply -f test-ingress.yaml
[root@vmnode1 ~]# kubectl get ingress
NAME HOSTS ADDRESS PORTS AGE
test-ingress test.apache.ingress,test.nginx.ingress 80 1m
本文 nginx-ingress-controller运行在vmnode2,vmnode3,vmnode4三个节点上。如果网络中有dns服务器,在dns中把这两个域名映射到nginx-ingress-controller运行的任意一个节点上,如果没有dns服务器只能修改host文件了。
备注: 正规的做法是在vmnode2,vmnode3,vmnode4这三个节点上安装keepalive,生成一个vip。在dns上把域名和vip做映射。
我这里直接在vmnode1节点上操作了。
##192.168.123.82,192.168.123.83,192.168.123.84 三个ip任选。
[root@vmnode1 ~]# echo '192.168.123.82 test.apache.ingress' >> /etc/hosts
[root@vmnode1 ~]# echo '192.168.123.83 test.nginx.ingress' >> /etc/hosts
测试test.nginx.ingress
[root@vmnode1 ~]# curl test.nginx.ingress
<!DOCTYPE html><html><head><title>Welcome to nginx!</title><style>
body { width: 35em; margin: 0 auto; font-family: Tahoma, Verdana, Arial, sans-serif; }</style></head><body><h1>Welcome to nginx!</h1><p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p><p>For online documentation and support please refer to<a href="http://nginx.org/">nginx.org</a>.<br/>Commercial support is available at<a href="http://nginx.com/">nginx.com</a>.</p><p><em>Thank you for using nginx.</em></p></body></html>
测试test.apache.ingress
[root@vmnode1 ~]# curl test.apache.ingress
<html><body><h1>It works!</h1></body></html>
如果不修改hosts文件可以通过下面的命令测试
##通过-H 指定模拟的域名
[root@vmnode1 ~]# curl -v http://192.168.123.83 -H 'host: test.apache.ingress'
[root@vmnode1 ~]# curl -v http://192.168.123.83 -H 'host: test.nginx.ingress'
https://jimmysong.io/kubernetes-handbook/practice/traefik-ingress-installation.html http://blog.csdn.net/hekanhyde/article/details/78672931 https://github.com/kubernetes/ingress-nginx/tree/master/deploy https://kubernetes.io/docs/concepts/services-networking/ingress/
本文转载自:https://blog.csdn.net/newcrane/article/details/79092577