794 lines
24 KiB
Markdown
794 lines
24 KiB
Markdown
# 概念以及原理
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Kubernetes`Service`定义了这样⼀种抽象：
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⼀个`Pod`的逻辑分组，⼀种可以访问它们的策略，通常称为微服务。这⼀组`Pod`能够被`Service`访问到，通常是通过`LabelSelector`
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<img src="Service/image-20240912140110844.png" alt="image-20240912140110844" style="zoom: 33%;" />
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Service在很多情况下只是一个概念，真正起作用的其实是kube-proxy服务进程，每个Node节点上都运行着一个kube-proxy服务进程。当创建Service的时候会通过api-server向etcd写入创建的service的信息，而kube-proxy会基于监听的机制发现这种Service的变动，然后**它会将最新的Service信息转换成对应的访问规则**。
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<img src="Service/image-20240912152844652.png" alt="image-20240912152844652" style="zoom:33%;" />
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# 工作模式
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kube-proxy目前支持三种工作模式:
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## userspace模式
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userspace模式下，kube-proxy会为每一个Service创建一个监听端口，发向Cluster IP的请求被Iptables规则重定向到kube-proxy监听的端口上，kube-proxy根据LB算法选择一个提供服务的Pod并和其建立链接，以将请求转发到Pod上。 该模式下，kube-proxy充当了一个四层负责均衡器的角色。由于kube-proxy运行在userspace中，在进行转发处理时会增加内核和用户空间之间的数据拷贝，虽然比较稳定，但是效率比较低。
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<img src="Service/image-20240912170627727.png" alt="image-20240912170627727" style="zoom:33%;" />
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## iptables模式
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iptables模式下，kube-proxy为service后端的每个Pod创建对应的iptables规则，直接将发向Cluster IP的请求重定向到一个Pod IP。该模式下kube-proxy不承担四层负责均衡器的角色，只负责创建iptables规则。该模式的优点是较userspace模式效率更高，但不能提供灵活的LB策略，当后端Pod不可用时也无法进行重试。
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<img src="Service/image-20240912170931956.png" alt="image-20240912170931956" style="zoom:33%;" />
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## ipvs模式
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ipvs模式和iptables类似，kube-proxy监控Pod的变化并创建相应的ipvs规则。ipvs相对iptables转发效率更高。除此以外，ipvs支持更多的LB算法。
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<img src="Service/image-20240912171043118.png" alt="image-20240912171043118" style="zoom:33%;" />
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```yaml
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# 创建三个pod
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apiVersion: apps/v1
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kind: Deployment
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metadata:
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labels:
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app: myapp-deploy
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name: myapp-deploy
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spec:
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replicas: 3
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selector:
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matchLabels:
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app: myapp-deploy
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template:
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metadata:
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labels:
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app: myapp-deploy
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spec:
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containers:
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- name: myapp
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image: aaronxudocker/myapp:v1.0
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resources:
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limits:
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memory: "128Mi"
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cpu: "500m"
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ports:
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- containerPort: 80
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```
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```bash
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# 启动一个负载均衡的service
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$ kubectl create svc clusterip myapp-deploy --tcp=80:80
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# 修改ipvs
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$ kubectl edit configmap kube-proxy -n kube-system
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mode: "ipvs"
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# 删除kube-proxy的pod
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$ kubectl delete pod -n kube-system -l k8s-app=kube-proxy
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pod "kube-proxy-ckwsj" deleted
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pod "kube-proxy-t729f" deleted
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pod "kube-proxy-z6dt8" deleted
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# 查看pod创建的状态
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$ kubectl get pod -n kube-system -l k8s-app=kube-proxy
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NAME READY STATUS RESTARTS AGE
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kube-proxy-948s5 1/1 Running 0 3s
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kube-proxy-ggpwj 1/1 Running 0 3s
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kube-proxy-v7lgs 1/1 Running 0 3s
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# 查看虚拟IP地址
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$ kubectl get svc
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
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myapp-deploy ClusterIP 10.9.86.78 <none> 80/TCP 6m54s
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# 查看ipvsadm的状态
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$ ipvsadm -Ln
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IP Virtual Server version 1.2.1 (size=4096)
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Prot LocalAddress:Port Scheduler Flags
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-> RemoteAddress:Port Forward Weight ActiveConn InActConn
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TCP 10.9.86.78:80 rr
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-> 10.244.140.106:80 Masq 1 0 0
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-> 10.244.196.141:80 Masq 1 0 0
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-> 10.244.196.142:80 Masq 1 0 0
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# 负载均衡的地址正好对应着pod的ip地址
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$ kubectl get pod -o wide
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NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS
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myapp-deploy-57bff895d5-b2hhk 1/1 Running 0 73s 10.244.196.142 node01 <none> <none>
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myapp-deploy-57bff895d5-fbln4 1/1 Running 0 73s 10.244.140.106 node02 <none> <none>
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myapp-deploy-57bff895d5-frnfd 1/1 Running 0 73s 10.244.196.141 node01 <none> <none>
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```
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# Service资源清单
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```yaml
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kind: Service # 资源类型
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apiVersion: v1 # 资源版本
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metadata: # 元数据
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name: service # 资源名称
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namespace: default # 命名空间
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spec: # 描述
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selector: # 标签选择器，用于确定当前service代理哪些pod
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app: nginx
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type: # Service类型，指定service的访问方式
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clusterIP: # 虚拟服务的ip地址
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sessionAffinity: # session亲和性，支持ClientIP、None两个选项
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sessionAffinityConfig:
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clientIP:
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timeoutSeconds: 120 # session的过期时间
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ports: # 端口信息
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- protocol: TCP
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port: 3017 # service端口
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targetPort: 5003 # pod端口
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nodePort: 31122 # 主机端口
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```
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可以使用如下命令得到基本的yaml格式的文件
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```bash
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$ kubectl create svc clusterip nginx --tcp=80:80 --dry-run=client -o yaml
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$ ipvsadm -lnc
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```
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`spec.type`可以选择的类型
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- ClusterIP：默认值，它是Kubernetes系统自动分配的虚拟IP，只能在集群内部访问
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- NodePort：将Service通过指定的Node上的端口暴露给外部，通过此方法，就可以在集群外部访问服务
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- LoadBalancer：使用外接负载均衡器完成到服务的负载分发，注意此模式需要外部云环境支持
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- ExternalName： 把集群外部的服务引入集群内部，直接使用
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# Service使用
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```yaml
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# 创建三个pod
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apiVersion: apps/v1
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kind: Deployment
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metadata:
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labels:
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app: myapp-deploy
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name: myapp-deploy
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spec:
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replicas: 3
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selector:
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matchLabels:
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app: myapp-deploy
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template:
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metadata:
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labels:
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app: myapp-deploy
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spec:
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containers:
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- name: myapp
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image: aaronxudocker/myapp:v1.0
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resources:
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limits:
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memory: "128Mi"
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cpu: "500m"
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ports:
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- containerPort: 80
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```
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测试三个pod
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```bash
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$ kubectl get pod -o wide
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NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
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myapp-deploy-57bff895d5-b2hhk 1/1 Running 0 30m 10.244.196.142 node01 <none> <none>
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myapp-deploy-57bff895d5-fbln4 1/1 Running 0 30m 10.244.140.106 node02 <none> <none>
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myapp-deploy-57bff895d5-frnfd 1/1 Running 0 30m 10.244.196.141 node01 <none> <none>
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# 查看一下访问情况
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$ curl 10.244.196.142/hostname.html
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myapp-deploy-57bff895d5-b2hhk
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$ curl 10.244.140.106/hostname.html
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myapp-deploy-57bff895d5-fbln4
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$ curl 10.244.196.141/hostname.html
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myapp-deploy-57bff895d5-frnfd
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```
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## ClusterIP类型的Service
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```yaml
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apiVersion: v1
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kind: Service
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metadata:
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name: service-clusterip
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spec:
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selector:
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app: myapp-deploy
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# clusterIP: 172.16.66.66 # service的ip地址，如果不写，默认会生成一个
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type: ClusterIP
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ports:
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- port: 80 # Service端口
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targetPort: 80 # pod端口
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```
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查看运行结果
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```bash
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$ kubectl get svc
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
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service-clusterip ClusterIP 10.13.125.29 <none> 80/TCP 22s
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$ kubectl describe svc service-clusterip
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Name: service-clusterip
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Namespace: default
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Labels: <none>
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Annotations: <none>
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Selector: app=myapp-deploy
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Type: ClusterIP
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IP Family Policy: SingleStack
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IP Families: IPv4
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IP: 10.13.125.29
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IPs: 10.13.125.29
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Port: <unset> 80/TCP
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TargetPort: 80/TCP
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Endpoints: 10.244.140.106:80,10.244.196.141:80,10.244.196.142:80
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Session Affinity: None
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Events: <none>
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$ ipvsadm -Ln
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IP Virtual Server version 1.2.1 (size=4096)
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Prot LocalAddress:Port Scheduler Flags
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-> RemoteAddress:Port Forward Weight ActiveConn InActConn
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TCP 10.13.125.29:80 rr
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-> 10.244.140.106:80 Masq 1 0 0
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-> 10.244.196.141:80 Masq 1 0 0
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-> 10.244.196.142:80 Masq 1 0 0
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$ while true;do curl 10.13.125.29/hostname.html; done
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myapp-deploy-57bff895d5-b2hhk
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myapp-deploy-57bff895d5-frnfd
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myapp-deploy-57bff895d5-fbln4
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myapp-deploy-57bff895d5-b2hhk
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myapp-deploy-57bff895d5-frnfd
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myapp-deploy-57bff895d5-fbln4
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```
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## Endpoint
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Endpoint是kubernetes中的一个资源对象，存储在etcd中，用来记录一个service对应的所有pod的访问地址，它是根据service配置文件中selector描述产生的。必须要满足就绪探测。
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一个Service由一组Pod组成，这些Pod通过Endpoints暴露出来，**Endpoints是实现实际服务的端点集合**。换句话说，service和pod之间的联系是通过endpoints实现的。
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<img src="Service/image-20240912172501813.png" alt="image-20240912172501813" style="zoom:33%;" />
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```bash
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$ kubectl get endpoints -o wide
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NAME ENDPOINTS AGE
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service-clusterip 10.244.140.106:80,10.244.196.141:80,10.244.196.142:80 6m27s
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```
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在deployment中添加一个就绪探测
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```yaml
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apiVersion: apps/v1
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kind: Deployment
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metadata:
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labels:
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app: myapp-deploy
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name: myapp-deploy
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spec:
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replicas: 3
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selector:
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matchLabels:
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app: myapp-deploy
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template:
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metadata:
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labels:
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app: myapp-deploy
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spec:
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containers:
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- name: myapp
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image: aaronxudocker/myapp:v1.0
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resources:
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limits:
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memory: "128Mi"
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cpu: "500m"
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readinessProbe:
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httpGet:
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port: 80
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path: /index1.html
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initialDelaySeconds: 1
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periodSeconds: 3
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ports:
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- containerPort: 80
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```
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在不满足就绪探测的情况下，是不会被endpoint采用的
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```bash
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$ kubectl get pod
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NAME READY STATUS RESTARTS AGE
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myapp-deploy-659f9975b8-2sntn 0/1 Running 0 40s
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myapp-deploy-659f9975b8-nd66b 0/1 Running 0 40s
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myapp-deploy-659f9975b8-p4j5k 0/1 Running 0 40s
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$ kubectl get endpoints
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NAME ENDPOINTS AGE
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service-clusterip 10s
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```
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满足了就绪探测和标签被匹配上的pod会被加入endpoint中
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```bash
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$ kubectl exec -it myapp-deploy-659f9975b8-2sntn -- /bin/bash
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root@myapp-deploy-659f9975b8-2sntn:/# echo "hello world" > /usr/share/nginx/html/index1.html
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$ kubectl get pod
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NAME READY STATUS RESTARTS AGE
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myapp-deploy-659f9975b8-2sntn 1/1 Running 0 3m4s
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myapp-deploy-659f9975b8-nd66b 0/1 Running 0 3m4s
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myapp-deploy-659f9975b8-p4j5k 0/1 Running 0 3m4s
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$ kubectl get endpoints
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NAME ENDPOINTS AGE
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service-clusterip 10.244.140.107:80 3m1s
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$ ipvsadm -L -n
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IP Virtual Server version 1.2.1 (size=4096)
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Prot LocalAddress:Port Scheduler Flags
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-> RemoteAddress:Port Forward Weight ActiveConn InActConn
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TCP 10.12.150.224:80 rr
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-> 10.244.140.107:80 Masq 1 0 0
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```
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**负载分发策略**
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对Service的访问被分发到了后端的Pod上去，目前kubernetes提供了两种负载分发策略：
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- 如果不定义，默认使用kube-proxy的策略，比如随机、轮询
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- 基于客户端地址的会话保持模式，即来自同一个客户端发起的所有请求都会转发到固定的一个Pod上
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此模式可以使在spec中添加`sessionAffinity: ClientIP`选项
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```bash
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$ kubectl edit svc service-clusterip
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sessionAffinity: ClientIP
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$ while true;do curl 10.13.125.29/hostname.html; done
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myapp-deploy-57bff895d5-fbln4
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myapp-deploy-57bff895d5-fbln4
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myapp-deploy-57bff895d5-fbln4
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myapp-deploy-57bff895d5-fbln4
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myapp-deploy-57bff895d5-fbln4
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myapp-deploy-57bff895d5-fbln4
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myapp-deploy-57bff895d5-fbln4
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myapp-deploy-57bff895d5-fbln4
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$ ipvsadm -Ln
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IP Virtual Server version 1.2.1 (size=4096)
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Prot LocalAddress:Port Scheduler Flags
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-> RemoteAddress:Port Forward Weight ActiveConn InActConn
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TCP 10.13.125.29:80 rr persistent 10800
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-> 10.244.140.106:80 Masq 1 0 155
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-> 10.244.196.141:80 Masq 1 0 0
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-> 10.244.196.142:80 Masq 1 0 0
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```
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## HeadLess类型的Service
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在某些场景中，开发人员可能不想使用Service提供的负载均衡功能，而希望自己来控制负载均衡策略，针对这种情况，kubernetes提供了HeadLiness Service，这类Service不会分配Cluster IP，如果想要访问service，只能通过service的域名进行查询。
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```yaml
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apiVersion: v1
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kind: Service
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metadata:
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name: service-headliness
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spec:
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selector:
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app: myapp-deploy
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clusterIP: None # 将clusterIP设置为None，即可创建headliness Service
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type: ClusterIP
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ports:
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- port: 80
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targetPort: 80
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```
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```bash
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$ kubectl get svc -o wide
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
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service-headliness ClusterIP None <none> 80/TCP 40s app=myapp-deploy
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$ kubectl describe svc service-headliness
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Name: service-headliness
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Namespace: default
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Labels: <none>
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Annotations: <none>
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Selector: app=myapp-deploy
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Type: ClusterIP
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IP Family Policy: SingleStack
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IP Families: IPv4
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IP: None
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IPs: None
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Port: <unset> 80/TCP
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TargetPort: 80/TCP
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Endpoints: 10.244.140.107:80
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Session Affinity: None
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Events: <none>
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$ kubectl exec -it myapp-deploy-659f9975b8-2sntn -- /bin/bash
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root@myapp-deploy-659f9975b8-2sntn:/# cat /etc/resolv.conf
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nameserver 10.0.0.10
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search default.svc.cluster.local svc.cluster.local cluster.local
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options ndots:5
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$ dig @10.0.0.10 service-headliness.default.svc.cluster.local
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;; ANSWER SECTION:
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service-headliness.default.svc.cluster.local. 30 IN A 10.244.140.107
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service-headliness.default.svc.cluster.local. 30 IN A 10.244.196.145
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service-headliness.default.svc.cluster.local. 30 IN A 10.244.196.144
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```
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## NodePort类型的Service
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|
||
在之前的样例中，创建的Service的ip地址只有集群内部才可以访问，如果希望将Service暴露给集群外部使用，那么就要使用到另外一种类型的Service，称为NodePort类型。NodePort的工作原理其实就是**将service的端口映射到Node的一个端口上**，然后就可以通过`NodeIp:NodePort`来访问service了。
|
||
|
||
<img src="Service/image-20240913143156247.png" alt="image-20240913143156247" style="zoom:33%;" />
|
||
|
||
```yaml
|
||
apiVersion: v1
|
||
kind: Service
|
||
metadata:
|
||
name: service-nodeport
|
||
spec:
|
||
selector:
|
||
app: myapp-deploy
|
||
type: NodePort # service类型
|
||
ports:
|
||
- port: 80
|
||
nodePort: 30002 # 指定绑定的node的端口(默认的取值范围是：30000-32767), 如果不指定，会默认分配
|
||
targetPort: 80
|
||
```
|
||
|
||
查看是否能够正常的访问
|
||
|
||
```bash
|
||
$ for i in {1..6};do curl 192.168.173.100:30002/hostname.html;done
|
||
myapp-deploy-659f9975b8-nd66b
|
||
myapp-deploy-659f9975b8-p4j5k
|
||
myapp-deploy-659f9975b8-2sntn
|
||
myapp-deploy-659f9975b8-nd66b
|
||
myapp-deploy-659f9975b8-p4j5k
|
||
myapp-deploy-659f9975b8-2sntn
|
||
```
|
||
|
||
## LoadBalancer类型的Service
|
||
|
||
LoadBalancer和NodePort很相似，目的都是向外部暴露一个端口，区别在于LoadBalancer会在集群的外部再来做一个负载均衡设备，而这个设备需要外部环境支持的，外部服务发送到这个设备上的请求，会被设备负载之后转发到集群中。
|
||
|
||
|
||
|
||
## ExternalName类型的Service
|
||
|
||
ExternalName类型的Service用于引入集群外部的服务，它通过`externalName`属性指定外部一个服务的地址，然后在集群内部访问此service就可以访问到外部的服务了。
|
||
|
||
<img src="Service/image-20240913160143805.png" alt="image-20240913160143805" style="zoom:33%;" />
|
||
|
||
```yaml
|
||
apiVersion: v1
|
||
kind: Service
|
||
metadata:
|
||
name: service-externalname
|
||
namespace: dev
|
||
spec:
|
||
type: ExternalName # service类型
|
||
externalName: www.baidu.com #改成ip地址也可以
|
||
```
|
||
|
||
```bash
|
||
$ kubectl get svc
|
||
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
|
||
service-externalname ExternalName <none> www.baidu.com <none> 7s
|
||
|
||
$ dig @10.0.0.10 service-externalname.default.svc.cluster.local
|
||
;; ANSWER SECTION:
|
||
service-externalname.default.svc.cluster.local. 30 IN CNAME www.baidu.com.
|
||
www.baidu.com. 30 IN CNAME www.a.shifen.com.
|
||
www.a.shifen.com. 30 IN A 180.101.50.242
|
||
www.a.shifen.com. 30 IN A 180.101.50.188
|
||
```
|
||
|
||
# Ingress介绍
|
||
|
||
在前面课程中已经提到，Service对集群之外暴露服务的主要方式有两种：NotePort和LoadBalancer，但是这两种方式，都有一定的缺点：
|
||
|
||
- NodePort方式的缺点是会占用很多集群机器的端口，那么当集群服务变多的时候，这个缺点就愈发明显
|
||
- LB方式的缺点是每个service需要一个LB，浪费、麻烦，并且需要kubernetes之外设备的支持
|
||
|
||
基于这种现状，kubernetes提供了Ingress资源对象，Ingress只需要一个NodePort或者一个LB就可以满足暴露多个Service的需求。工作机制大致如下图表示：
|
||
|
||
<img src="Service/image-20240913161756342.png" alt="image-20240913161756342" style="zoom:33%;" />
|
||
|
||
实际上，Ingress相当于一个7层的负载均衡器，是kubernetes对反向代理的一个抽象，它的工作原理类似于Nginx，可以理解成在**Ingress里建立诸多映射规则，Ingress Controller通过监听这些配置规则并转化成Nginx的反向代理配置 , 然后对外部提供服务**。在这里有两个核心概念：
|
||
|
||
- ingress：kubernetes中的一个对象，作用是定义请求如何转发到service的规则
|
||
- ingress controller：具体实现反向代理及负载均衡的程序，对ingress定义的规则进行解析，根据配置的规则来实现请求转发，实现方式有很多，比如Nginx, Contour, Haproxy等等
|
||
|
||
Ingress（以Nginx为例）的工作原理如下：
|
||
|
||
1. 用户编写Ingress规则，说明哪个域名对应kubernetes集群中的哪个Service
|
||
2. Ingress控制器动态感知Ingress服务规则的变化，然后生成一段对应的Nginx反向代理配置
|
||
3. Ingress控制器会将生成的Nginx配置写入到一个运行着的Nginx服务中，并动态更新
|
||
4. 到此为止，其实真正在工作的就是一个Nginx了，内部配置了用户定义的请求转发规则
|
||
|
||
<img src="Service/image-20240914142642245.png" alt="image-20240914142642245" style="zoom:33%;" />
|
||
|
||
## 安装helm
|
||
|
||
```bash
|
||
# 安装helm，helm在kubernetes中相当于yum，是可以在线去获取资源清单，快速部署服务
|
||
$ curl -fsSL -o get_helm.sh https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3
|
||
$ chmod 700 get_helm.sh
|
||
$ ./get_helm.sh
|
||
|
||
# 初始化,可以从 https://artifacthub.io/ 中选择一个可用的仓库地址
|
||
$ helm repo add bitnami https://charts.bitnami.com/bitnami
|
||
$ helm repo list
|
||
NAME URL
|
||
bitnami https://charts.bitnami.com/bitnami
|
||
|
||
# 常见操作
|
||
$ helm repo update # 更新chart列表
|
||
$ helm show chart bitnami/apache # 查看chart基本信息
|
||
$ helm install bitnami/apache --generate-name # 部署chart
|
||
$ helm list # 查看部署包，加上--all可以看到所有的
|
||
$ helm uninstall apache-1726297430 # 删除这个安装包所有的kubernetes资源
|
||
|
||
$ helm search hub wordpress # 在 helm hub(https://hub.helm.sh)上搜索helm chart
|
||
$ helm search repo wordpress # 在repo中搜索
|
||
```
|
||
|
||
## 安装Ingress-nginx
|
||
|
||
```bash
|
||
$ helm repo add ingress-nginx https://kubernetes.github.io/ingress-nginx
|
||
$ helm pull ingress-nginx/ingress-nginx
|
||
|
||
# 修改 values.yaml 文件
|
||
修改 hostNetwork 的值为 true
|
||
dnsPolicy的值改为: ClusterFirstWithHostNet
|
||
kind类型更改为：DaemonSet
|
||
ingressClassResource.default:true
|
||
|
||
# 关闭所有镜像的 digest
|
||
|
||
# 如果是本地的helm chart，使用这个命令安装
|
||
$ kubectl create ns ingress
|
||
$ helm install ingress-nginx -n ingress . -f values.yaml
|
||
$ kubectl get pod -n ingress
|
||
NAME READY STATUS RESTARTS AGE
|
||
ingress-nginx-controller-7c4x8 1/1 Running 0 12s
|
||
ingress-nginx-controller-bjk4s 1/1 Running 0 12s
|
||
```
|
||
|
||
## 实验测试
|
||
|
||
创建如下两个资源模型
|
||
|
||
|
||
|
||
```yaml
|
||
apiVersion: apps/v1
|
||
kind: Deployment
|
||
metadata:
|
||
name: nginx-deployment
|
||
spec:
|
||
replicas: 3
|
||
selector:
|
||
matchLabels:
|
||
app: nginx
|
||
template:
|
||
metadata:
|
||
labels:
|
||
app: nginx
|
||
spec:
|
||
containers:
|
||
- name: nginx
|
||
image: aaronxudocker/myapp:v1.0
|
||
ports:
|
||
- containerPort: 80
|
||
|
||
---
|
||
|
||
apiVersion: apps/v1
|
||
kind: Deployment
|
||
metadata:
|
||
name: tomcat-deployment
|
||
spec:
|
||
replicas: 3
|
||
selector:
|
||
matchLabels:
|
||
app: tomcat
|
||
template:
|
||
metadata:
|
||
labels:
|
||
app: tomcat
|
||
spec:
|
||
containers:
|
||
- name: tomcat
|
||
image: tomcat:8.5-jre10-slim
|
||
ports:
|
||
- containerPort: 8080
|
||
|
||
---
|
||
|
||
apiVersion: v1
|
||
kind: Service
|
||
metadata:
|
||
name: nginx-service
|
||
spec:
|
||
selector:
|
||
app: nginx
|
||
clusterIP: None
|
||
type: ClusterIP
|
||
ports:
|
||
- port: 80
|
||
targetPort: 80
|
||
|
||
---
|
||
|
||
apiVersion: v1
|
||
kind: Service
|
||
metadata:
|
||
name: tomcat-service
|
||
spec:
|
||
selector:
|
||
app: tomcat
|
||
clusterIP: None
|
||
type: ClusterIP
|
||
ports:
|
||
- port: 8080
|
||
targetPort: 8080
|
||
```
|
||
|
||
### Http代理
|
||
|
||
```yaml
|
||
apiVersion: networking.k8s.io/v1
|
||
kind: Ingress
|
||
metadata:
|
||
name: ingress-nginx
|
||
spec:
|
||
rules:
|
||
- host: nginx.iproute.cn
|
||
http:
|
||
paths:
|
||
- path: /
|
||
pathType: Prefix
|
||
backend:
|
||
service:
|
||
name: nginx-service
|
||
port:
|
||
number: 80
|
||
ingressClassName: nginx
|
||
---
|
||
|
||
apiVersion: networking.k8s.io/v1
|
||
kind: Ingress
|
||
metadata:
|
||
name: ingress-tomcat
|
||
spec:
|
||
rules:
|
||
- host: tomcat.iproute.cn
|
||
http:
|
||
paths:
|
||
- path: /
|
||
pathType: Prefix
|
||
backend:
|
||
service:
|
||
name: tomcat-service
|
||
port:
|
||
number: 8080
|
||
ingressClassName: nginx
|
||
```
|
||
|
||
查看运行状态
|
||
|
||
```bash
|
||
$ kubectl get ing
|
||
NAME CLASS HOSTS ADDRESS PORTS AGE
|
||
ingress-nginx nginx nginx.iproute.cn 80 7s
|
||
ingress-tomcat nginx tomcat.iproute.cn 80 7s
|
||
|
||
$ kubectl describe ing
|
||
|
||
Rules:
|
||
Host Path Backends
|
||
---- ---- --------
|
||
nginx.iproute.cn
|
||
/ nginx-service:80 (10.244.140.109:80,10.244.196.149:80,10.244.196.150:80)
|
||
|
||
Rules:
|
||
Host Path Backends
|
||
---- ---- --------
|
||
tomcat.iproute.cn
|
||
/ tomcat-service:8080 (10.244.140.110:8080,10.244.196.151:8080,10.244.196.153:8080)
|
||
```
|
||
|
||
访问测试
|
||
|
||
|
||
|
||
其中nginx多次访问主机名，可以看到负载均衡
|
||
|
||
|
||
|
||
## Https代理
|
||
|
||
创建证书
|
||
|
||
```bash
|
||
# 生成证书
|
||
$ openssl req -x509 -sha256 -nodes -days 365 -newkey rsa:2048 -keyout tls.key -out tls.crt -subj "/C=CN/ST=BJ/L=BJ/O=nginx/CN=iproute.cn"
|
||
|
||
# 创建密钥
|
||
$ kubectl create secret tls tls-secret --key tls.key --cert tls.crt
|
||
```
|
||
|
||
创建资源清单
|
||
|
||
```yaml
|
||
apiVersion: networking.k8s.io/v1
|
||
kind: Ingress
|
||
metadata:
|
||
name: https-nginx
|
||
spec:
|
||
tls:
|
||
- hosts:
|
||
- nginx.iproute.cn
|
||
secretName: tls-secret # 指定秘钥
|
||
rules:
|
||
- host: nginx.iproute.cn
|
||
http:
|
||
paths:
|
||
- path: /
|
||
pathType: Prefix
|
||
backend:
|
||
service:
|
||
name: nginx-service
|
||
port:
|
||
number: 80
|
||
ingressClassName: nginx
|
||
---
|
||
|
||
apiVersion: networking.k8s.io/v1
|
||
kind: Ingress
|
||
metadata:
|
||
name: tomcat-https
|
||
spec:
|
||
tls:
|
||
- hosts:
|
||
- tomcat.iproute.cn
|
||
secretName: tls-secret # 指定秘钥
|
||
rules:
|
||
- host: tomcat.iproute.cn
|
||
http:
|
||
paths:
|
||
- path: /
|
||
pathType: Prefix
|
||
backend:
|
||
service:
|
||
name: tomcat-service
|
||
port:
|
||
number: 8080
|
||
ingressClassName: nginx
|
||
```
|
||
|
||
访问测试
|
||
|
||
|
||
|
||
可以看到负载均衡
|
||
|
||
|