Serverless Kubernetes容器服務支援pod掛載彈性公網IP
阿新 • • 發佈：2019-01-07
近日，阿里雲Serverless Kubernetes服務推出pod掛載彈性公網IP功能，此功能使某些serverless容器應用的部署和服務訪問變得更加簡單和便利。
- 無需建立VPC NAT閘道器即可讓單個pod訪問公網
- 無需建立service也可讓單個pod暴露公網服務
- 可以更加靈活而且動態的繫結pod和eip
目前Serverless Kubernetes支援兩種方法掛載eip，支援自動分配eip，或者指定eip例項進行繫結。
方法一：自動分配彈性公網IP
通過指定Annonation "k8s.aliyun.com/enable-eip"為"true"，serverless kubernetes服務會自動為此pod分配一個eip，並且繫結到pod上。
示例：
#cat nginx-enable-eip-pod.yaml apiVersion: v1 kind: Pod metadata: name: nginx annotations: "k8s.aliyun.com/enable-eip": "true" spec: containers: - image: registry-vpc.cn-hangzhou.aliyuncs.com/jovi/nginx:alpine imagePullPolicy: Always name: nginx ports: - containerPort: 80 name: http protocol: TCP restartPolicy: OnFailure
建立pod：
#kubectl apply -f nginx-enable-eip-pod.yaml
pod "nginx" created
#kubectl get pod
nginx 1/1 Running 0 20s檢視pod的ip地址：
# kubectl describe pod Name: nginx Namespace: default Node: viking-c7d16b6c584544f65bfa4eba3a8b04d63/ Start Time: Mon, 07 Jan 2019 13:19:47 +0800 Labels: <none> Annotations: k8s.aliyun.com/allocated-eipAddress=47.96.67.132 k8s.aliyun.com/allocated-eipInstanceId=eip-bp1wtbt7vp18tgu5g7rb2 k8s.aliyun.com/enable-eip=true kubectl.kubernetes.io/last-applied-configuration={"apiVersion":"v1","kind":"Pod","metadata":{"annotations":{"k8s.aliyun.com/enable-eip":"true"},"name":"nginx","namespace":"default"},"spec":{"container... kubernetes.io/limit-ranger=LimitRanger plugin set: cpu, memory request for container nginx Status: Running IP: 10.1.89.103 Containers: nginx: Container ID: eci://779380281b08b325b4b7a1b66c4cb9e706985b25cde0c36345af93a308745b95 Image: registry-vpc.cn-hangzhou.aliyuncs.com/jovi/nginx:alpine Image ID: Port: 80/TCP State: Running Started: Mon, 07 Jan 2019 13:19:47 +0800 Ready: True Restart Count: 0 Requests: cpu: 1 memory: 2Gi Environment: <none> ... # kubectl describe pod|grep allocated-eipAddress Annotations: k8s.aliyun.com/allocated-eipAddress=47.96.67.132
我們可以看到在pod的Annotations中顯示了已分配的eip，通過此eip可直接訪問pod。
# curl 47.96.67.132
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
...因為此方式中eip為動態分配，其生命週期與pod相同，當pod被刪除時，動態分配的eip也會被一同刪除。
方法二：指定彈性公網IP例項id
首先使用者需要在eip控制檯購買彈性公網eip。
通過指定pod的Annonation "k8s.aliyun.com/eipInstanceId"為eip例項id，如下：
# cat nginx-eipid-pod.yaml
apiVersion: v1
kind: Pod
metadata:
name: nginx
annotations:
"k8s.aliyun.com/eipInstanceId": "eip-bp19trewkig3i9pnek99i"
spec:
containers:
- image: registry-vpc.cn-hangzhou.aliyuncs.com/jovi/nginx:alpine
imagePullPolicy: Always
name: nginx
ports:
- containerPort: 80
name: http
protocol: TCP
restartPolicy: OnFailure建立pod
# kubectl apply -f nginx-eipid-pod.yaml
pod "nginx" created
# kubectl get pod
NAME READY STATUS RESTARTS AGE
nginx 1/1 Running 0 20s通過eip訪問pod：
# curl 47.111.20.92
<!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>
...此種方式種當pod被刪除時，pod和eip解除繫結。pod重新建立時eip則會重新被繫結。
快速試用Serverless Kubernetes
歡迎登入容器服務控制檯，公測期間免費使用，https://cs.console.aliyun.com/#/k8s
如在使用中有任何問題，歡迎掃碼加入Serverless K8s釘釘群進行討論