767 lines
21 KiB
Markdown
767 lines
21 KiB
Markdown
# Pod生命周期
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init容器与普通的容器非常像，除了如下两点：
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- init容器总是运行到成功完成为止
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- 每个init容器都必须在下一个init容器启动之前成功完成
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如果Pod的Init容器失败，Kubernetes会不断地重启该Pod，直到Init容器成功为止。然而，如果Pod对应的restartPolicy为Never，它不会重新启动
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## 检测initC的阻塞性
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```yaml
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apiVersion: v1
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kind: Pod
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metadata:
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name: initc-1
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labels:
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name: initc
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spec:
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containers:
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- name: myapp-container
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image: centos:7
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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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command: ['sh', '-c', 'echo The app is running && sleep 10']
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initContainers:
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- name: init-myservice
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image: aaronxudocker/tools:busybox
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command: ['sh', '-c', 'until nslookup myservice; do echo waiting for myservice; sleep 2; done;']
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- name: init-mydb
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image: aaronxudocker/tools:busybox
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command: ['sh', '-c', 'until nslookup mydb; do echo waiting for mydb; sleep 2; done;']
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```
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```bash
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# 查看日志，看到不停的在尝试
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$ kubectl logs initc-1 -c init-myservice
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# 创建svc资源，会通过CoreDNS自动将myservice解析成功，详解看后面的service部分
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$ kubectl create svc clusterip myservice --tcp=80:80
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```
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如果initc执行失败了，那么就会重新执行所有的initc
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```yaml
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apiVersion: v1
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kind: Pod
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metadata:
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name: initc-2
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labels:
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name: initc
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spec:
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containers:
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- name: myapp-container
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image: centos:7
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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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command: ['sh', '-c', 'echo The app is running && sleep 10']
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initContainers:
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- name: init-myservice
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image: aaronxudocker/tools:busybox
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command: ['sh', '-c', 'until nslookup myservice; do echo waiting for myservice; sleep 2; done;']
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- name: randexit
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image: aaronxudocker/tools:randexitv1
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args: ['--exitcode=1']
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```
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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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initc-1 0/1 Init:1/2 0 16m
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initc-2 0/1 Init:Error 5 (97s ago) 3m42s
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$ kubectl logs initc-2 -c randexit
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休眠 4 秒，返回码为 1！
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```
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如果我们让initc的返回码直接为0，那么就可以看到pod正常启动
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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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initc-1 0/1 Init:1/2 0 19m
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initc-2 1/1 Running 1 (7s ago) 72s
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```
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- InitC与应用容器具备不同的镜像，可以把一些危险的工具放置在initC中，进行使用
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- initC多个之间是线性启动的，所以可以做一些延迟性的操作
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- initC无法定义readinessProbe，其它以外同应用容器定义无异
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# Pod探针
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探针是由kubelet对容器执行的定期诊断。要执行诊断，kubelet调用由容器实现的Handler。有三种类型的处理程序：
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- ExecAction：在容器内执行指定命令。如果命令退出时返回码为0则认为诊断成功
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- TCPSocketAction：对指定端口上的容器的IP地址进行TCP检查。如果端口打开，则诊断被认为是成功的
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- HTTPGetAction：对指定的端口和路径上的容器的IP地址执行HTTPGet请求。如果响应的状态码⼤于等于200且小于400，则诊断被认为是成功的
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每次探测都将获得以下三种结果之一：
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- 成功：容器通过了诊断。
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- 失败：容器未通过诊断。
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- 未知：诊断失败，因此不会采取任何行动
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## 探针的分类
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- startupProbe：开始探针，开始检测吗？
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- livenessProbe：存活探针，还活着吗？
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- readinessProbe：就绪探针，准备提供服务了吗？
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### readinessProbe就绪探针
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介绍：k8s通过添加就绪探针，解决尤其是在扩容时保证提供给用户的服务都是可用的。
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> 选项说明
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> - initialDelaySeconds：容器启动后要等待多少秒后就探针开始工作，单位“秒”，默认是0秒，最小值是0
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> - periodSeconds：执行探测的时间间隔（单位是秒），默认为10s，单位“秒”，最小值是1
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> - timeoutSeconds：探针执行检测请求后，等待响应的超时时间，默认为1s，单位“秒”，最小值是1
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> - successThreshold：探针检测失败后认为成功的最小连接成功次数，默认值为1。必须为1才能激活和启动。最小值为1。
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> - failureThreshold：探测失败的重试次数，重试一定次数后将认为失败，默认值为3，最小值为1。
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#### 就绪探针实验
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- 基于 HTTP GET 方式
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```yaml
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apiVersion: v1
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kind: Pod
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metadata:
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name: readiness-httpget-pod
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labels:
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name: myapp
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spec:
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containers:
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- name: readiness-httpget-container
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image: nginx:latest
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imagePullPolicy: IfNotPresent
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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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resources:
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limits:
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memory: "128Mi"
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cpu: "500m"
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```
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```bash
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# 当前处于没有就绪的状态
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$ kubectl get pod
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NAME READY STATUS RESTARTS AGE
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readiness-httpget-pod 0/1 Running 0 4m16s
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# 创建一个index1.html
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$ kubectl exec -it readiness-httpget-pod -c readiness-httpget-container -- /bin/bash
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root@readiness-httpget-pod:/# echo "hehe" > /usr/share/nginx/html/index1.html
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# 查看就已经处于就绪的状态了
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$ kubectl get pod
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NAME READY STATUS RESTARTS AGE
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readiness-httpget-pod 1/1 Running 0 5m40s
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# 在运行过程中，就绪探测一直存在，如果不满足条件，会回到未就绪的情况
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```
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- 基于 EXEC 方式
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```yaml
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apiVersion: v1
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kind: Pod
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metadata:
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name: readiness-exec-pod
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labels:
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name: myapp
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spec:
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containers:
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- name: readiness-exec-container
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image: aaronxudocker/tools:busybox
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imagePullPolicy: IfNotPresent
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command: ["/bin/sh", "-c", "touch /tmp/live ; sleep 60; rm -rf /tmp/live; sleep 3600"]
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readinessProbe:
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exec:
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command: ["test", "-e", "/tmp/live"]
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initialDelaySeconds: 1
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periodSeconds: 3
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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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```
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```bash
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# 可以看到在60秒后就变成非就绪状态了
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$ kubectl get pod -w
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NAME READY STATUS RESTARTS AGE
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readiness-exec-pod 1/1 Running 0 7s
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readiness-exec-pod 0/1 Running 0 69s
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```
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基于TCP Check方式
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```yaml
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apiVersion: v1
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kind: Pod
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metadata:
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name: readiness-tcp-pod
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labels:
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name: myapp
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spec:
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containers:
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- name: readiness-tcp-container
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image: nginx:latest
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imagePullPolicy: IfNotPresent
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readinessProbe:
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tcpSocket:
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port: 80
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initialDelaySeconds: 1
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periodSeconds: 3
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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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```
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#### 就绪探针流量测试
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<img src="Pod生命周期/image-20240906140721572.png" alt="image-20240906140721572" style="zoom: 25%;" />
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在匹配可用pod的时候，标签必须匹配，状态必须是就绪状态。
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```yaml
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# pod-1.yaml
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apiVersion: v1
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kind: Pod
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metadata:
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name: pod-1
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labels:
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app: myapp
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spec:
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containers:
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- name: myapp-1
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image: nginx:latest
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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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# pod-2.yaml
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apiVersion: v1
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kind: Pod
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metadata:
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name: pod-2
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labels:
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app: myapp
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version: v1
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spec:
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containers:
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- name: myapp-1
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image: nginx:latest
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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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# 确认状态已经就绪
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$ kubectl get pod --show-labels
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NAME READY STATUS RESTARTS AGE LABELS
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pod-1 1/1 Running 0 2m31s app=myapp
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pod-2 1/1 Running 0 32s app=myapp,version=v1
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```
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创建service资源
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```bash
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# 注意myapp就是标签为app=myapp的pod
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# 此处不需要理解，后面会细讲，只是用来验证就绪探针对流量的影响
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# 此处的作用是形成多个pod的负载均衡
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$ kubectl create svc clusterip myapp --tcp=80:80
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service/myapp created
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$ kubectl get svc
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
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kubernetes ClusterIP 10.0.0.1 <none> 443/TCP 46h
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myapp ClusterIP 10.8.74.201 <none> 80/TCP 6s
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```
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将两个pod中的主页文件修改一下，用来作为区分
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```bash
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# 如果pod中只有一个main容器，那么在exec的时候就不需要指定容器
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$ kubectl exec -it pod-1 -- /bin/bash
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root@pod-1:/# echo pod-1 > /usr/share/nginx/html/index.html
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$ kubectl exec -it pod-2 -- /bin/bash
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root@pod-2:/# echo pod-2 > /usr/share/nginx/html/index.html
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```
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验证负载均衡的状态
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```bash
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$ curl 10.8.74.201
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pod-2
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$ curl 10.8.74.201
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pod-1
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$ curl 10.8.74.201
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pod-2
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```
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创建一个label为 `app: test` 的pod，看下是否能被匹配
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```yaml
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# 3.yaml
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apiVersion: v1
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kind: Pod
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metadata:
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name: pod-3
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labels:
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app: test
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version: v1
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spec:
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containers:
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- name: myapp-1
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image: nginx:latest
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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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```
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查看pod状态，修改 `pod-3` 的网页内容
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```bash
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$ kubectl get pod --show-labels
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NAME READY STATUS RESTARTS AGE LABELS
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pod-1 1/1 Running 0 11m app=myapp
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pod-2 1/1 Running 0 9m57s app=myapp,version=v1
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pod-3 1/1 Running 0 51s app=test,version=v1
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$ kubectl exec -it pod-3 -- /bin/bash
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root@pod-3:/# echo pod-3 > /usr/share/nginx/html/index.html
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```
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验证负载均衡的状态,发现 `pod-3` 并不能被匹配上
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```bash
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$ curl 10.8.74.201
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pod-1
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$ curl 10.8.74.201
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pod-2
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$ curl 10.8.74.201
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pod-1
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$ curl 10.8.74.201
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pod-2
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$ curl 10.8.74.201
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pod-2
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$ curl 10.8.74.201
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pod-1
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```
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创建一个不满足就绪条件的 `pod-4`
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```yaml
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apiVersion: v1
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kind: Pod
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metadata:
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name: pod-4
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labels:
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app: myapp
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version: v1
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spec:
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containers:
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- name: myapp-1
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image: nginx:latest
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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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resources:
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limits:
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memory: "128Mi"
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cpu: "500m"
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```
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修改主页内容
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```bash
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$ kubectl exec -it pod-4 -- /bin/bash
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root@pod-4:/# echo pod-4 > /usr/share/nginx/html/index.html
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```
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查看状态是未就绪的
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```bash
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$ kubectl get pod --show-labels
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NAME READY STATUS RESTARTS AGE LABELS
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pod-1 1/1 Running 0 17m app=myapp
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pod-2 1/1 Running 0 15m app=myapp,version=v1
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pod-3 1/1 Running 0 6m49s app=test,version=v1
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pod-4 0/1 Running 0 41s app=myapp,version=v1
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```
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验证负载均衡
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```bash
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$ curl 10.8.74.201
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pod-1
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$ curl 10.8.74.201
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pod-2
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$ curl 10.8.74.201
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pod-1
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$ curl 10.8.74.201
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pod-2
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$ curl 10.8.74.201
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pod-2
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$ curl 10.8.74.201
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pod-1
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```
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满足 `pod-4` 的就绪条件
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```bash
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$ kubectl exec -it pod-4 -- /bin/bash
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root@pod-4:/# touch /usr/share/nginx/html/index1.html
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```
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再次验证负载均衡
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```bash
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$ curl 10.8.74.201
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pod-1
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$ curl 10.8.74.201
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pod-2
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$ curl 10.8.74.201
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pod-4
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```
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|
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### livenessProbe存活探针
|
||
|
||
介绍：k8s通过添加存活探针，解决虽然活着但是已经死了的问题。
|
||
|
||
> 选项说明
|
||
> - initialDelaySeconds：容器启动后要等待多少秒后就探针开始工作，单位“秒”，默认是0秒，最小值是0
|
||
> - periodSeconds：执行探测的时间间隔（单位是秒），默认为10s，单位“秒”，最小值是1
|
||
> - timeoutSeconds：探针执行检测请求后，等待响应的超时时间，默认为1s，单位“秒”，最小值是1
|
||
> - successThreshold：探针检测失败后认为成功的最小连接成功次数，默认值为1。必须为1才能激活和启动。最小值为1。
|
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> - failureThreshold：探测失败的重试次数，重试一定次数后将认为失败，默认值为3，最小值为1。
|
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|
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#### 存活探针实验
|
||
|
||
- 基于 Exec 方式
|
||
|
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```yaml
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apiVersion: v1
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kind: Pod
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metadata:
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name: liveness-exec-pod
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spec:
|
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containers:
|
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- name: liveness-exec-container
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image: aaronxudocker/tools:busybox
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imagePullPolicy: IfNotPresent
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command: ["/bin/sh", "-c", "touch /tmp/live; sleep 60; rm -rf /tmp/live; sleep 3600"]
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livenessProbe:
|
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exec:
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command: ["test", "-e", "/tmp/live"]
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initialDelaySeconds: 1
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periodSeconds: 3
|
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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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```
|
||
|
||
一段时间以后，可以看到发生重启的事件
|
||
|
||
```bash
|
||
$ kubectl get pod -w
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NAME READY STATUS RESTARTS AGE
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liveness-exec-pod 1/1 Running 0 11s
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liveness-exec-pod 1/1 Running 1 (1s ago) 101s
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liveness-exec-pod 1/1 Running 2 (1s ago) 3m20s
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```
|
||
|
||
- 基于 HTTP Get 方式
|
||
|
||
```yaml
|
||
apiVersion: v1
|
||
kind: Pod
|
||
metadata:
|
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name: liveness-httpget-pod
|
||
spec:
|
||
containers:
|
||
- name: liveness-httpget-container
|
||
image: nginx:latest
|
||
imagePullPolicy: IfNotPresent
|
||
livenessProbe:
|
||
httpGet:
|
||
port: 80
|
||
path: /index.html
|
||
initialDelaySeconds: 1
|
||
periodSeconds: 3
|
||
timeoutSeconds: 3
|
||
resources:
|
||
limits:
|
||
memory: "128Mi"
|
||
cpu: "500m"
|
||
```
|
||
|
||
删除 `index.html` 文件，使其不满足存活探测条件
|
||
|
||
```bash
|
||
# 在删除index.html之后，可以看到命令行退出了
|
||
$ kubectl exec -it liveness-httpget-pod -- /bin/bash
|
||
root@liveness-httpget-pod:/# rm -f /usr/share/nginx/html/index.html
|
||
root@liveness-httpget-pod:/# command terminated with exit code 137
|
||
```
|
||
|
||
重新查看pod状态，可以看到重启了
|
||
|
||
```bash
|
||
$ kubectl get pod
|
||
NAME READY STATUS RESTARTS AGE
|
||
liveness-httpget-pod 1/1 Running 1 (48s ago) 2m39s
|
||
```
|
||
|
||
在运行此pod的节点上查看docker的名字，容器名字是 `集群名-pod名-容器名-hash-重启次数(初始是0)`
|
||
|
||
```bash
|
||
$ docker ps -a |grep liveness-exec-container
|
||
18c5ba02d684 39286ab8a5e1 "/docker-entrypoint.…" About a minute ago Up About a minute k8s_liveness-exec-container_liveness-httpget-pod_default_aa36504e-23a9-48d1-988c-4de0398c474f_1
|
||
54b3a04bd6b0 39286ab8a5e1 "/docker-entrypoint.…" 3 minutes ago Exited (0) About a minute ago k8s_liveness-exec-container_liveness-httpget-pod_default_aa36504e-23a9-48d1-988c-4de0398c474f_0
|
||
```
|
||
|
||
- 基于 TCP Check 方式
|
||
|
||
```yaml
|
||
apiVersion: v1
|
||
kind: Pod
|
||
metadata:
|
||
name: liveness-tcp-pod
|
||
spec:
|
||
containers:
|
||
- name: liveness-tcp-container
|
||
image: nginx:latest
|
||
imagePullPolicy: IfNotPresent
|
||
livenessProbe:
|
||
tcpSocket:
|
||
port: 80
|
||
initialDelaySeconds: 1
|
||
periodSeconds: 3
|
||
timeoutSeconds: 3
|
||
resources:
|
||
limits:
|
||
memory: "128Mi"
|
||
cpu: "500m"
|
||
```
|
||
|
||
### startupProbe启动探针
|
||
|
||
介绍：k8s在1.16版本后增加startupProbe探针，主要解决在复杂的程序中readinessProbe、livenessProbe探针无法更好的判断程序是否启动、是否存活。
|
||
|
||
> 选项说明
|
||
> - initialDelaySeconds：容器启动后要等待多少秒后就探针开始工作，单位“秒”，默认是0秒，最小值是0
|
||
> - periodSeconds：执行探测的时间间隔（单位是秒），默认为10s，单位“秒”，最小值是1
|
||
> - timeoutSeconds：探针执行检测请求后，等待响应的超时时间，默认为1s，单位“秒”，最小值是1
|
||
> - successThreshold：探针检测失败后认为成功的最小连接成功次数，默认值为1。必须为1才能激活和启动。最小值为1。
|
||
> - failureThreshold：探测失败的重试次数，重试一定次数后将认为失败，默认值为3，最小值为1。
|
||
|
||
#### 启动探针实验
|
||
|
||
```yaml
|
||
apiVersion: v1
|
||
kind: Pod
|
||
metadata:
|
||
name: startupprobe-1
|
||
spec:
|
||
containers:
|
||
- name: startupprobe
|
||
image: nginx:latest
|
||
imagePullPolicy: IfNotPresent
|
||
readinessProbe:
|
||
httpGet:
|
||
port: 80
|
||
path: /index2.html
|
||
initialDelaySeconds: 1
|
||
periodSeconds: 3
|
||
startupProbe:
|
||
httpGet:
|
||
path: /index1.html
|
||
port: 80
|
||
periodSeconds: 10
|
||
failureThreshold: 30
|
||
resources:
|
||
limits:
|
||
memory: "128Mi"
|
||
cpu: "500m"
|
||
|
||
# 应用程序将会有最多 5 分钟 failureThreshold * periodSeconds（30 * 10 = 300s）的时间来完成其启动过程。如果到超时都没有启动完成，就会重启。
|
||
```
|
||
|
||
创建 `index1.html` 文件
|
||
|
||
```bash
|
||
$ kubectl exec -it pod/startupprobe-1 -- /bin/bash
|
||
root@startupprobe-1:/# touch /usr/share/nginx/index1.html
|
||
|
||
# 查看依旧是未就绪的状态
|
||
$ kubectl get pod
|
||
NAME READY STATUS RESTARTS AGE
|
||
startupprobe-1 0/1 Running 0 42s
|
||
|
||
# 创建index2.html文件
|
||
$ kubectl exec -it pod/startupprobe-1 -- /bin/bash
|
||
root@startupprobe-1:/# touch /usr/share/nginx/index2.html
|
||
|
||
# 查看状态
|
||
$ kubectl get pod
|
||
NAME READY STATUS RESTARTS AGE
|
||
startupprobe-1 1/1 Running 0 43s
|
||
```
|
||
|
||
此时删掉启动探测的 `index1.html` 会怎样？
|
||
|
||
# Pod钩子
|
||
|
||
Podhook（钩子）是由Kubernetes管理的kubelet发起的，当容器中的进程启动前或者容器中的进程终止之前运行，这是包含在容器的⽣命周期之中。可以同时为Pod中的所有容器都配置hook
|
||
|
||
Hook的类型包括两种：
|
||
- exec：执行一段命令
|
||
- HTTP：发送HTTP请求
|
||
|
||
在k8s中，理想的状态是pod优雅释放，但是并不是每一个Pod都会这么顺利
|
||
- Pod卡死，处理不了优雅退出的命令或者操作
|
||
- 优雅退出的逻辑有BUG，陷入死循环
|
||
- 代码问题，导致执行的命令没有效果
|
||
|
||
对于以上问题，k8s的Pod终止流程中还有一个"最多可以容忍的时间"，即graceperiod(在pod.spec.terminationGracePeriodSeconds字段定义)，这个值默认是30秒，当我们执行kubectl delete的时候也可以通过--grace-period参数显示指定一个优雅退出时间来覆盖Pod中的配置，如果我们配置的grace period超过时间之后，k8s就只能选择强制kill Pod。
|
||
|
||
值得注意的是，这与preStopHook和SIGTERM信号并行发⽣。k8s不会等待preStopHook完成。你的应用程序应在terminationGracePeriod之前退出。
|
||
|
||
## Pod钩子实验
|
||
|
||
- 基于 exec 方式
|
||
|
||
```yaml
|
||
apiVersion: v1
|
||
kind: Pod
|
||
metadata:
|
||
name: hook-exec-pod
|
||
spec:
|
||
containers:
|
||
- name: hook-exec-container
|
||
image: nginx:latest
|
||
imagePullPolicy: IfNotPresent
|
||
lifecycle:
|
||
postStart:
|
||
exec:
|
||
command: ["/bin/sh", "-c", "echo postStart > /usr/share/message"]
|
||
preStop:
|
||
exec:
|
||
command: ["/bin/sh", "-c", "echo preStart > /usr/share/message"]
|
||
resources:
|
||
limits:
|
||
memory: "128Mi"
|
||
cpu: "500m"
|
||
```
|
||
|
||
在这个pod的内部，写一个循环查看此文件的shell命令
|
||
|
||
```bash
|
||
$ kubectl exec -it pod/hook-exec-pod -- /bin/bash
|
||
root@hook-exec-pod:/# while true;
|
||
> do
|
||
> cat /usr/share/message
|
||
> done
|
||
|
||
# 删除此pod就能看到结束的钩子信息了
|
||
```
|
||
|
||
- 基于 HTTP Get 方式
|
||
|
||
```bash
|
||
# 开启一个测试 webserver
|
||
$ docker run -it --rm -p 1234:80 nginx:latest
|
||
```
|
||
|
||
启动一个pod，然后再删除，查看nginx容器日志，可以看到记录了这两次的http请求
|
||
|
||
```yaml
|
||
2024/09/06 07:35:23 [error] 29#29: *1 open() "/usr/share/nginx/html/poststarthook.html" failed (2: No such file or directory), client: 192.168.173.101, server: localhost, request: "GET /poststarthook.html HTTP/1.1", host: "192.168.173.100:1234"
|
||
192.168.173.101 - - [06/Sep/2024:07:35:23 +0000] "GET /poststarthook.html HTTP/1.1" 404 153 "-" "kube-lifecycle/1.29" "-"
|
||
2024/09/06 07:35:45 [error] 29#29: *1 open() "/usr/share/nginx/html/prestophook.html" failed (2: No such file or directory), client: 192.168.173.101, server: localhost, request: "GET /prestophook.html HTTP/1.1", host: "192.168.173.100:1234"
|
||
192.168.173.101 - - [06/Sep/2024:07:35:45 +0000] "GET /prestophook.html HTTP/1.1" 404 153 "-" "kube-lifecycle/1.29" "-"
|
||
```
|
||
|
||
# 总结
|
||
|
||
Pod⽣命周期中的initC、startupProbe、livenessProbe、readinessProbe、hook都是可以并且存在的，可以选择全部、部分或者完全不用。
|
||
|
||
```yaml
|
||
apiVersion: v1
|
||
kind: Pod
|
||
metadata:
|
||
name: lifecycle-pod
|
||
labels:
|
||
app: lifecycle-pod
|
||
spec:
|
||
containers:
|
||
- name: busybox-container
|
||
image: aaronxudocker/tools:busybox
|
||
command: ["/bin/sh","-c","touch /tmp/live ; sleep 600; rm -rf /tmp/live; sleep 3600"]
|
||
livenessProbe:
|
||
exec:
|
||
command: ["test","-e","/tmp/live"]
|
||
initialDelaySeconds: 1
|
||
periodSeconds: 3
|
||
lifecycle:
|
||
postStart:
|
||
httpGet:
|
||
host: 192.168.173.100
|
||
path: poststarthook.html
|
||
port: 1234
|
||
preStop:
|
||
httpGet:
|
||
host: 192.168.173.100
|
||
path: prestophook.html
|
||
port: 1234
|
||
resources:
|
||
limits:
|
||
memory: "128Mi"
|
||
cpu: "500m"
|
||
- name: myapp-container
|
||
image: nginx:latest
|
||
livenessProbe:
|
||
httpGet:
|
||
port: 80
|
||
path: /index.html
|
||
initialDelaySeconds: 1
|
||
periodSeconds: 3
|
||
timeoutSeconds: 3
|
||
readinessProbe:
|
||
httpGet:
|
||
port: 80
|
||
path: /index1.html
|
||
initialDelaySeconds: 1
|
||
periodSeconds: 3
|
||
initContainers:
|
||
- name: init-myservice
|
||
image: aaronxudocker/tools:busybox
|
||
command: ['sh', '-c', 'until nslookup myservice; do echo waiting for myservice; sleep 2; done;']
|
||
- name: init-mydb
|
||
image: aaronxudocker/tools:busybox
|
||
command: ['sh', '-c', 'until nslookup mydb; do echo waiting for mydb; sleep 2; done;']
|
||
```
|
||
|
||
# 调度Pod
|
||
|
||
|
||
|