pod生命周期-重启策略
容器探测器一旦出现异常k8s就会对容器所在的pod进行重启，其中pod的重启策略有三种分别是
always：容器失效便自动重启该容器（默认）
onfailure：容器终止运行且退出码不为0时重启
never：不论状态如何都不重启该容器
重启策略适用于pod对象中的所有容器，首次需要重启的容器，将在其需要时立即进行重启，随后再次需要重启的操作将由kubelet延迟一段时间进行，反复重启的操作延迟以10s,20s,40s,80s,160s,300s。300s是最大时长
下面看一下实验
pod-restartpolicy.yaml
apiVersion: v1
kind: Pod
metadata:
name: pod-restartpolicy
namespace: dev
spec:
containers:
- name: nginx
image: nginx:1.17.1
ports:
- name: nginx-port
containerPort: 80
livenessProbe:
httpGet:
scheme: HTTP
port: 80
path: /hello
restartPolicy: Never # 设置重启策略为Never# 创建Pod
[qq@k8s-master01 ~]# kubectl create -f pod-restartpolicy.yaml
pod/pod-restartpolicy created
# 查看Pod详情，发现nginx容器失败
[qq@k8s-master01 ~]# kubectl describe pods pod-restartpolicy -n dev
......
Warning Unhealthy 15s (x3 over 35s) kubelet, node1 Liveness probe failed: HTTP probe failed with statuscode: 404
Normal Killing 15s kubelet, node1 Container nginx failed liveness probe
# 多等一会，再观察pod的重启次数，发现一直是0，并未重启
[qq@k8s-master01 ~]# kubectl get pods pod-restartpolicy -n dev
NAME READY STATUS RESTARTS AGE
pod-restartpolicy 0/1 Running 0 5min42s