文章目录
-
-
- 控制器含义解释
- pod的标签与注释
- ReplicaController
- ReplicaSet
- Deployments
- DaemonSet
- Job
- Cronjob
-
控制器含义解释
空调遥控器知道吧
ReplicationController: ReplicationController确保在任何时候都运行指定数量的pod副本。换句话说，一个ReplicationController确保一个pod或一组同类的pod总是处于可用状态。
ReplicaSet: ReplicaSet的目的是维护在任何给定时间运行的一组稳定的pod副本。因此，它通常用于保证指定数量的相同pod的可用性。
Deployments: 部署针对Pods和ReplicaSets提供了宣告式的更新。
StatefulSets: StatefulSet常用于管理有状态的应用。
DaemonSet: 它是确保所有的节点或一些节点都运行一个Pod的复本。
pod的标签与注释
标签就是名字的意思
kubectl run httpd \
--image=httpd:2.4 \
--replicas=1 \
--labels="ver=2,env=prod"
查看标签
kubectl get deployment --show-labels
kubectl label deployments httpd "canary=true"
kubectl get deployment -L canary
移除
kubectl get deployment -L canary
显示标签 kubectl get pods --show-labels
选择标签为某个值
kubectl get pod --selector="ver=2"
标签是抓取pod的唯一依据
ReplicaController
管理它自己管理的pod数量保持一致
[root@k8s-01 chapter04]# cat web-rc.yaml
apiVersion: v1
kind: ReplicationController
metadata:
name: web
spec:
replicas: 3
selector:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx
ports:
- containerPort: 80
[root@k8s-01 chapter04]# kubectl create -f web-rc.yaml
replicationcontroller/web created
[root@k8s-01 chapter04]# kubectl get pod
NAME READY STATUS RESTARTS AGE
httpd 1/1 Running 0 22m
httpd-1 1/1 Running 0 21m
nginx-97499b967-jzxwg 1/1 Running 0 14h
web-5bq9k 0/1 ContainerCreating 0 4s
web-rvbmm 0/1 ContainerCreating 0 4s
web-x6wxd 0/1 ContainerCreating 0 4s
[root@k8s-01 chapter04]# kubectl get rc
NAME DESIRED CURRENT READY AGE
web 3 3 0 14s
[root@k8s-01 chapter04]# kubectl get replicationController
NAME DESIRED CURRENT READY AGE
web 3 3 1 27s
如果删除一个pod ，会自己新增一个pod
kubectl delete pod/web-x6wxd
新增一个标签看看
[root@k8s-01 chapter04]# kubectl get pod --show-labels
NAME READY STATUS RESTARTS AGE LABELS
nginx-97499b967-jzxwg 1/1 Running 0 14h app=nginx,pod-template-hash=97499b967
web-rftd7 1/1 Running 0 4m16s app=nginx
web-rvbmm 1/1 Running 0 7m35s app=nginx
web-x6wxd 1/1 Running 0 7m35s app=nginx
[root@k8s-01 chapter04]# kubectl label pod web-rftd7 type=special
pod/web-rftd7 labeled
[root@k8s-01 chapter04]# kubectl get pod --show-labels
NAME READY STATUS RESTARTS AGE LABELS
nginx-97499b967-jzxwg 1/1 Running 0 14h app=nginx,pod-template-hash=97499b967
web-rftd7 1/1 Running 0 5m20s app=nginx,type=special
web-rvbmm 1/1 Running 0 8m39s app=nginx
web-x6wxd 1/1 Running 0 8m39s app=nginx
覆盖过去
kubectl label pod web-rftd7 app=nginx1 --overwrite
添加pod的标签
# kubectl label pod web-z8stj type=special
更改pod的标签
# kubectl label pod web-z8stj app=foo --overwrite
再次列出pod
# kubectl get pods –L app
修改rc的数量为2个
[root@k8s-01 chapter04]# kubectl get rc
NAME DESIRED CURRENT READY AGE
web 3 3 3 17m
[root@k8s-01 chapter04]# kubectl edit rc web
replicationcontroller/web edited
[root@k8s-01 chapter04]# kubectl get rc
NAME DESIRED CURRENT READY AGE
web 2 2 2 18m
修改里面的数量为2 个
水平扩缩容
[root@k8s-01 chapter04]# kubectl scale rc web --replicas=6
replicationcontroller/web scaled
[root@k8s-01 chapter04]# kubectl get pod
NAME READY STATUS RESTARTS AGE
nginx-97499b967-jzxwg 1/1 Running 0 14h
web-fhg2l 0/1 ContainerCreating 0 4s
web-nsxsh 0/1 ContainerCreating 0 4s
web-pcwkz 0/1 ContainerCreating 0 4s
web-rvbmm 1/1 Running 0 19m
web-vj48d 0/1 ContainerCreating 0 4s
web-x6wxd 1/1 Running 0 19m
kubectl delete rc web ,删除rc
RC (ReplicaController) 通过标签来控制pod的，改变pod的标签，pod会进行变化
ReplicaSet
针对rc而言，选择更加灵活
kubectl describe rs
[root@k8s-01 chapter04]# cat web-replicaset.yaml
apiVersion: apps/v1
kind: ReplicaSet
metadata:
name: web
spec:
replicas: 3
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx
生产环境用rs多些
Deployments
Deployment为Pods和ReplicaSets提供声明式的更新。
在部署中描述一个期望的状态，部署控制器以某个控制的速率改变实际的状态到期望的状态
控制更新的节奏和速率
[root@k8s-01 chapter04]# cat nginx-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: nginx
spec:
replicas: 3
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
ports:
- containerPort: 80
创建
# kubectl apply –f nginx-deployment.yaml
查看部署
# kubectl get deployment
查看部署的状态
# kubectl rollout status deployment.v1.apps/nginx-deployment
查看通过部署创建的rs
# kubectl get rs
查看pod自动产生的labels
# kubectl get pods –show-labels
更新nginx:1.7.9为nginx:1.9.1
# kubectl –record deployment.apps/nginx-deployment set image deployment.v1.apps/nginx-deployment nginx=nginx:1.9.1
或者：
# kubectl set image deployment/nginx-deployment nginx=nginx:1.9.1 –record
或者：
# kubectl edit deployment.v1.apps/nginx-deployment
查看更新的状态
# kubectl rollout status deployment.v1.apps/nginx-deployment
通过以下命令查看部署
# kubectl get deployment
查看部署的rs
# kubectl get rs
查看新的pods
# kubectl get pods
查看部署的详情
# kubectl describe deployments
回滚部署
更新一个不存在的镜像
# kubectl set image deployment.v1.apps/nginx-deployment nginx=nginx:1.91 –record=true
通过以下命令查看更新卡住了
# kubectl rollout status deployment.v1.apps/nginx-deployment
查看部署的rs
# kubectl get rs
查看部署的pods
# kubectl get pods
查看部署的描述信息
# kubectl describe deployment
查看部署的版本
# kubectl rollout history deployment.v1.apps/nginx-deployment
查看每个版本的详情
# kubectl rollout history deployment.v1.apps/nginx-deployment –revision=2
回退到先前的版本
# kubectl rollout undo deployment.v1.apps/nginx-deployment
回退到特定的版本
# kubectl rollout undo deployment.v1.apps/nginx-deployment --to-revision=2
检查回退是否成功
# kubectl get deployment nginx-deployment
部署的扩容
扩容副本数量为10
# kubectl scale deployment.v1.apps/nginx-deployment --replicas=10
如果启用了水平的pod自动扩容可以执行如下：
# kubectl autoscale deployment.v1.apps/nginx-deployment --min=10 --max=15 --cpu-percent=80
扩容的比例和刻度
确保部署的10个复本处于运行
# kubectl get deploy
更新一个不存在的镜像，并查看结果
# kubectl set image deployment.v1.apps/nginx-deployment nginx=nginx:sometag
# kubectl get rs
更新复本的数量为15个，再次查看结果,然后删除本次部署
# kubectl scale deployment.v1.apps/nginx-deployment --replicas=15
# kubectl get deployment
# kubectl get rs
# kubectl delete deploy nginx-deployment
暂停和继续部署
创建部署
# kubectl create –f nginx-deployment.yaml
暂停更新
# kubectl rollout pause deployment.v1.apps/nginx-deployment
更新镜像
# kubectl set image deployment.v1.apps/nginx-deployment nginx=nginx:1.9.1
查看是否有新的更新开始
# kubectl rollout history deployment.v1.apps/nginx-deployment
恢复部署
# kubectl rollout resume deployment.v1.apps/nginx-deployment
DaemonSet
使用DaemonSet在每个节点上运行一个pod
DaemonSet确保创建尽可能多的pod,并将每个pod部署到自己的节点上。
使用DaemonSet仅在特定的节点上运行Pods
这可以通过在pod模板中指定node-selector属性来完成的，它是DaemonSet定义的一部分
[root@k8s-01 chapter04]# cat ssd-monitor-daemonset.yaml
apiVersion: apps/v1
kind: DaemonSet
metadata:
name: ssd-monitor
spec:
selector:
matchLabels:
app: ssd-monitor
template:
metadata:
labels:
app: ssd-monitor
spec:
nodeSelector:
disk: ssd
containers:
- name: main
image: luksa/ssd-monitor
[root@k8s-01 chapter04]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-97499b967-jzxwg 1/1 Running 0 16h 10.244.1.2 k8s-02
打标签
kubectl label node k8s-02 disk=ssd
kubectl get ds
kubectl get pods
打完标签后指哪打哪
Job
这种是运行一次，直到完成
在Job完成后，它并不会删除Pod，允许我们可以查看它的日志
在Job中运行多个Pod实例
Job可以配置为创建多个Pod实例，依并行或有序的方式运行它们。
按顺序来运行Job
如果需要一个job运行多次，可以将completions设置为希望job的Pod运行多次。
配置请参考文件：multi-completion-batch-job.yaml
以并行的方式运行job pods.
如果让job并行运行多个pods，可以使用parallelism指定并运行pod的数量。
配置请参考文件：multi-completion-batch-job2.yaml
限制Job pod的完成时间
通过设置activedeadlinesecond属性
[root@k8s-01 chapter04]# cat multi-completion-batch-job.yaml
apiVersion: batch/v1
kind: Job
metadata:
name: multi-completion-batch-job
spec:
completions: 5
template:
metadata:
labels:
app: batch-job
spec:
restartPolicy: OnFailure
containers:
- name: main
image: luksa/batch-job
[root@k8s-01 chapter04]# cat multi-completion-batch-job2.yaml
apiVersion: batch/v1
kind: Job
metadata:
name: multi-completion-batch-job2
spec:
completions: 5
parallelism: 2
template:
metadata:
labels:
app: batch-job
spec:
restartPolicy: OnFailure
containers:
- name: main
image: luksa/batch-job
Cronjob
这个是定时计划任务，周期性的
[root@k8s-01 chapter04]# cat batch-job-every-fifteen-minutes.yaml
apiVersion: batch/v1beta1
# API group的版本是v1beat1,这里不要写错
kind: CronJob
metadata:
name: batch-job-every-fifteen-minutes
spec:
# 该任务将会在每小时的0，15，30，45分运行
schedule: "0,15,30,45 * * * *"
jobTemplate:
spec:
template:
metadata:
labels:
app: periodic-batch-job-every-fifteen-minutes
spec:
restartPolicy: OnFailure
containers:
- name: main
image: luksa/batch-job
[root@k8s-01 chapter04]# cat cronjob.yaml
apiVersion: batch/v1beta1
kind: CronJob
metadata:
name: hello
spec:
schedule: "*/1 * * * *"
jobTemplate:
spec:
template:
spec:
containers:
- name: hello
image: busybox
args:
- /bin/sh
- -c
- date; echo Hello from the kubernetes cluster
restartPolicy: OnFailure
使用以下命令获取它的状态
# kubectl get cronjob hello
也可以通过以下命令获取它的状态
# kubectl get jobs --watch
可以通过以下命令查看上次调度的时间
# kubectl get conrjob hello
删除cronjob
# kubectl delete cronjob hello
参考文档
https://edu.csdn.net/course/detail/27762?spm=1003.2449.3001.8295.2
