k8s - 4 - 技术栈

Pod 生命周期

init容器

root@master \~\]# **vim web1.yaml** > --- > > kind: Pod > > apiVersion: v1 > > metadata: > > name: web1 > > spec: > > **initContainers: # 定义初始化任务** > > **- name: task1 # 如果初始化任务失败，主容器不会启动** > > **image: myos:latest # 初始化可以使用不同的镜像** > > **command: \[sh\] # 任务，一般用脚本实现** > > **args: # 任务** > > **- -c # 任务** > > **- \| # 任务** > > **ID=${RANDOM} # 任务** > > **echo "${ID}" # 任务** > > **sleep 3 # 任务** > > **exit $((ID%2)) # 状态 0 成功，其他失败，如果失败会重新执行初始化** > > containers: > > - name: web > > image: myos:httpd \[root@master \~\]# **kubectl replace --force -f web1.yaml** > pod "web1" deleted > > pod/web1 replaced # 如果初始化任务失败就重复执行，直到成功为止 \[root@master \~\]#**kubectl get pods -w** > NAME READY STATUS RESTARTS AGE > > web1 0/1 Init:0/1 0 1s > > web1 0/1 Init:Error 0 6s > > web1 0/1 Init:0/1 1 (1s ago) 7s > > web1 0/1 PodInitializing 0 12s > > web1 1/1 Running 0 13s * **初始化失败** \[root@master \~\]# **vim web1.yaml** > --- > > kind: Pod > > apiVersion: v1 > > metadata: > > name: web1 > > spec: > > **restartPolicy: Never # 任务失败不重启** > > initContainers: > > - name: task1 > > image: myos:latest > > command: \[sh

args:

-c

|

ID=${RANDOM}

echo "${ID}"

sleep 3

exit $((ID%2))

containers:

name: web

image: myos:httpd

root@master \~\]# **kubectl replace --force -f web1.yaml** > pod "web1" deleted > > pod/web1 replaced # 初始化任务失败，main 容器不会运行 \[root@master \~\]#**kubectl get pods -w** > NAME READY STATUS RESTARTS AGE > > web1 0/1 Init:0/1 0 1s > > web1 0/1 Init:Error 0 5s * **多任务初始化** \[root@master \~\]# vim web1.yaml > --- > > kind: Pod > > apiVersion: v1 > > metadata: > > name: web1 > > spec: > > restartPolicy: Always > > initContainers: > > - name: task1 # 任务一 > > image: myos:latest > > command: \[sh

args:

-c

|

ID=${RANDOM}

echo "${ID}"

sleep 3

exit $((ID%2))

name: task2 # 任务二，多个任务顺序执行

image: myos:8.5

command: [sh]

args:

-c

|

ID=${RANDOM}

echo "${ID}"

sleep 3

exit $((ID%2))

containers:

name: web

image: myos:httpd