Kubernetes学习（三）

三 探针

readiness举例说明,就绪检测

read.yaml

apiVersion: v1
kind: Pod
metadata:
name: readiness-httpget-pod
namespace: default
spec:
containers:
- name: readiness-httpget-container
image: wangyanglinux/myapp:v1
imagePullPolicy: IfNotPresent
readinessProbe:
httpGet:
port: 80
path: /index1.html
initialDelaySeconds: 1
periodSeconds: 3

这个时候pod的状态是Running但是并没有ready，即该pod对外不可用

liveness举例说明，存活检测

live.yaml

#60s自动重启的POD。当liveness检测不通过的时候kubectl会杀死容器导致POD重启（根据定义的重启机制确定）
apiVersion: v1
kind: Pod
metadata:
name: liveness-exec-pod
namespace: default
spec:
containers:
- name: liveness-exec-container
image: busybox
imagePullPolicy: IfNotPresent
command: ['/bin/sh','-c','touch /tmp/live ; sleep 60; rm -f /tmp/live; sleep 3600']
livenessProbe:
exec:
command: ['test','-e','/tmp/live']
initialDelaySeconds: 1
periodSeconds: 3

live-tcp.yaml

apiVersion: v1
kind: Pod
metadata:
name: probe-tcp
spec:
containers:
- name: nginx
image: wangyanglinux/myapp:v1
imagePullPolicy: IfNotPresent
livenessProbe:
initialDelaySeconds: 5 #5s以后开始检测
timeoutSeconds: 1
tcpSocket:
port: 8080
periodSeconds: 3

live-http.yaml

apiVersion: v1
kind: Pod
metadata:
name: liveness-httpget-pod
namespace: default
spec:
containers:
- name: liveness-httpget-container
image: wangyanglinux/myapp:v1
imagePullPolicy: IfNotPresent
ports:
- name: http
containerPort: 80
livenessProbe:
httpGet:
port: http
path: /index.html
initialDelaySeconds: 1
periodSeconds: 3
timeoutSeconds: 10

readiness与liveness一起使用

apiVersion: v1
kind: Pod
metadata:
name: liveness-httpget-pod
namespace: default
spec:
containers:
- name: liveness-httpget-container
image: wangyanglinux/myapp:v1
imagePullPolicy: IfNotPresent
ports:
- name: http
containerPort: 80
readinessProbe:
httpGet:
port: 80
path: /index1.html
initialDelaySeconds: 1
periodSeconds: 3
livenessProbe:
httpGet:
port: http
path: /index.html
initialDelaySeconds: 1
periodSeconds: 3
timeoutSeconds: 10

此时pod的容器中没有index1.html文件，所以状态是running但是不是ready状态，如图

 

 

进入容器创建文件index1.html文件后pod的状态