1、基础知识
一个 Deployment 控制器为 Pods 和 ReplicaSets 提供声明式的更新能力。
你负责描述 Deployment 中的 目标状态，而 Deployment 控制器以受控速率更改实际状态， 使其变为期望状态。你可以定义 Deployment 以创建新的 ReplicaSet，或删除现有 Deployment， 并通过新的 Deployment 收养其资源。
注意：不要管理 Deployment 所拥有的 ReplicaSet 。
以下是 Deployments 的典型用例：
- 创建 Deployment 以将 ReplicaSet 上线。 ReplicaSet 在后台创建 Pods。 检查 ReplicaSet 的上线状态，查看其是否成功。
- 通过更新 Deployment 的 PodTemplateSpec，声明 Pod 的新状态 。 新的 ReplicaSet 会被创建，Deployment 以受控速率将 Pod 从旧 ReplicaSet 迁移到新 ReplicaSet。 每个新的 ReplicaSet 都会更新 Deployment 的修订版本。
- 如果 Deployment 的当前状态不稳定，回滚到较早的 Deployment 版本。 每次回滚都会更新 Deployment 的修订版本。
- 扩大 Deployment 规模以承担更多负载。
- 暂停 Deployment 以应用对 PodTemplateSpec 所作的多项修改， 然后恢复其执行以启动新的上线版本。
- 使用 Deployment 状态 来判定上线过程是否出现停滞。
- 清理较旧的不再需要的 ReplicaSet 。
2、命令行运行一个Deployment
[root@clientvm ~]# kubectl create deployment -hUsage:kubectl create deployment NAME --image=image -- [COMMAND] [args...] [options]Examples:# Create a deployment named my-dep that runs the busybox image.kubectl create deployment my-dep --image=busybox# Create a deployment with commandkubectl create deployment my-dep --image=busybox -- date# Create a deployment named my-dep that runs the nginx image with 3 replicas.kubectl create deployment my-dep --image=nginx --replicas=3# Create a deployment named my-dep that runs the busybox image and expose port 5701.kubectl create deployment my-dep --image=busybox --port=5701
Example：
## 创建[root@clientvm ~]# kubectl create deployment testdep --image=nginx -n mytestdeployment.apps/testdep created## 查看[root@clientvm k8s]# kubectl get deployments.apps -n mytestNAME READY UP-TO-DATE AVAILABLE AGEtestdep 1/1 1 1 44s[root@clientvm k8s]# kubectl get pod -n mytestNAME READY STATUS RESTARTS AGEtestdep-64c98ff7d7-9ph5j 1/1 Running 0 50s## 扩展[root@clientvm ~]# kubectl get deployments.apps -n mytestNAME READY UP-TO-DATE AVAILABLE AGEtestdep 2/2 2 2 4m6s[root@clientvm ~]# kubectl get pod -n mytestNAME READY STATUS RESTARTS AGEtestdep-64c98ff7d7-6drmb 1/1 Running 0 64stestdep-64c98ff7d7-9ph5j 1/1 Running 0 4m9s
3、创建Deployment
3.1 生成配置文件
[root@clientvm ~]# kubectl -n mytest create deployment dep-from-file --image=nginx --dry-run=client -o yaml >dep-from-file.yaml
3.2 根据需要修改配置
[root@clientvm ~]# vim dep-from-file.yaml[root@clientvm ~]#[root@clientvm ~]# cat dep-from-file.yamlapiVersion: apps/v1kind: Deploymentmetadata:labels:app: dep-from-filename: dep-from-filenamespace: mytestspec:replicas: 2selector:matchLabels:app: dep-from-filetemplate:metadata:creationTimestamp: nulllabels:app: dep-from-filespec:containers:- image: nginxname: nginximagePullPolicy: IfNotPresent
3.3 创建Deployment
[root@clientvm ~]# kubectl apply -f dep-from-file.yaml
deployment.apps/dep-from-file created
[root@clientvm ~]# kubectl get deployments.apps -n mytest
NAME READY UP-TO-DATE AVAILABLE AGE
dep-from-file 2/2 2 2 15s
testdep 2/2 2 2 12m
3.4 查看RS
[root@clientvm ~]# kubectl get rs -n mytest
NAME DESIRED CURRENT READY AGE
dep-from-file-7b78bc4877 2 2 2 72s
testdep-64c98ff7d7 2 2 2 13m
3.5 弹性伸缩
## 修改配置文件，修改replicas为4
[root@clientvm ~]# vim dep-from-file.yaml
[root@clientvm ~]# cat dep-from-file.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
app: dep-from-file
name: dep-from-file
namespace: mytest
spec:
replicas: 4
selector:
......
## 应用修改
[root@clientvm ~]# kubectl apply -f dep-from-file.yaml
deployment.apps/dep-from-file configured
## 查看
[root@clientvm ~]# kubectl get deployments.apps -n mytest
NAME READY UP-TO-DATE AVAILABLE AGE
dep-from-file 4/4 4 4 3m41s
3.6 滚动更新
[root@clientvm ~]# kubectl set image -h
Update existing container image(s) of resources.
Usage:
kubectl set image (-f FILENAME | TYPE NAME) CONTAINER_NAME_1=CONTAINER_IMAGE_1 ... CONTAINER_NAME_N=CONTAINER_IMAGE_N
[options]
Examples:
# Set a deployment's nginx container image to 'nginx:1.9.1', and its busybox container image to 'busybox'.
kubectl set image deployment/nginx busybox=busybox nginx=nginx:1.9.1
# Update all deployments' and rc's nginx container's image to 'nginx:1.9.1'
kubectl set image deployments,rc nginx=nginx:1.9.1 --all
# Update image of all containers of daemonset abc to 'nginx:1.9.1'
kubectl set image daemonset abc *=nginx:1.9.1
# Print result (in yaml format) of updating nginx container image from local file, without hitting the server
kubectl set image -f path/to/file.yaml nginx=nginx:1.9.1 --local -o yaml
Example 1：
[root@clientvm ~]# kubectl get deployments.apps -n mytest
NAME READY UP-TO-DATE AVAILABLE AGE
dep-from-file 4/4 4 4 2m32s
testdep 2/2 2 2 24m
[root@clientvm ~]#
[root@clientvm ~]# kubectl set image deployment dep-from-file nginx=nginx:1.9.1 -n mytest
deployment.apps/dep-from-file image updated
## 查看
[root@clientvm ~]# kubectl rollout status deployment dep-from-file -n mytest
deployment "dep-from-file" successfully rolled out
[root@clientvm ~]# kubectl rollout status deployment dep-from-file -n mytest
deployment "dep-from-file" successfully rolled out
[root@clientvm ~]# kubectl describe deployments.apps -n mytest dep-from-file
Name: dep-from-file
Namespace: mytest
......
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal ScalingReplicaSet 39m deployment-controller Scaled up replica set dep-from-file-7b78bc4877 to 4
Normal ScalingReplicaSet 34m deployment-controller Scaled up replica set dep-from-file-7dfb96d9dd to 1
Normal ScalingReplicaSet 34m deployment-controller Scaled down replica set dep-from-file-7b78bc4877 to 3
Normal ScalingReplicaSet 34m deployment-controller Scaled up replica set dep-from-file-7dfb96d9dd to 2
Normal ScalingReplicaSet 12m deployment-controller Scaled down replica set dep-from-file-7b78bc4877 to 2
Normal ScalingReplicaSet 12m deployment-controller Scaled up replica set dep-from-file-7dfb96d9dd to 3
Normal ScalingReplicaSet 11m deployment-controller Scaled down replica set dep-from-file-7b78bc4877 to 1
Normal ScalingReplicaSet 11m deployment-controller Scaled up replica set dep-from-file-7dfb96d9dd to 4
Normal ScalingReplicaSet 11m deployment-controller Scaled down replica set dep-from-file-7b78bc4877 to 0
Example 2：
[root@clientvm ~]# kubectl set image deployment dep-from-file nginx=nginx:1.8.1 -n mytest --record
deployment.apps/dep-from-file image updated
[root@master ~]# kubectl get pod -n mytest
NAME READY STATUS RESTARTS AGE
dep-from-file-7478c844bc-6x8d4 0/1 ContainerCreating 0 2m
dep-from-file-7478c844bc-bf2rw 1/1 Running 0 66s
dep-from-file-7478c844bc-krjj4 1/1 Running 0 2m
dep-from-file-7478c844bc-tvsv4 0/1 ContainerCreating 0 64s
dep-from-file-7dfb96d9dd-9hzls 1/1 Running 0 39m
[root@clientvm ~]# kubectl rollout status deployment dep-from-file -n mytest
Waiting for deployment "dep-from-file" rollout to finish: 2 out of 4 new replicas have been updated...
Waiting for deployment "dep-from-file" rollout to finish: 2 out of 4 new replicas have been updated...
Waiting for deployment "dep-from-file" rollout to finish: 2 out of 4 new replicas have been updated...
Waiting for deployment "dep-from-file" rollout to finish: 3 out of 4 new replicas have been updated...
Waiting for deployment "dep-from-file" rollout to finish: 3 out of 4 new replicas have been updated...
Waiting for deployment "dep-from-file" rollout to finish: 3 out of 4 new replicas have been updated...
Waiting for deployment "dep-from-file" rollout to finish: 1 old replicas are pending termination...
Waiting for deployment "dep-from-file" rollout to finish: 1 old replicas are pending termination...
Waiting for deployment "dep-from-file" rollout to finish: 1 old replicas are pending termination...
Waiting for deployment "dep-from-file" rollout to finish: 3 of 4 updated replicas are available...
deployment "dep-from-file" successfully rolled out
## 查看历史记录
[root@clientvm ~]# kubectl rollout history deployment -n mytest dep-from-file
deployment.apps/dep-from-file
REVISION CHANGE-CAUSE
1 <none>
2 <none>
3 kubectl set image deployment dep-from-file nginx=nginx:1.8.1 --namespace=mytest --record=true
## 查看历史记录详细信息
[root@clientvm ~]# kubectl rollout history deployment -n mytest dep-from-file --revision=3
## 回滚版本
[root@clientvm ~]# kubectl rollout undo deployment dep-from-file -n mytest --to-revision=2
deployment.apps/dep-from-file rolled back
[root@clientvm ~]# kubectl rollout status deployment dep-from-file -n mytest
deployment "dep-from-file" successfully rolled out
##验证Pod nginx版本
[root@clientvm ~]# kubectl edit pod dep-from-file-7dfb96d9dd-5hghh -n mytest
......
spec:
containers:
- image: nginx:1.9.1
imagePullPolicy: IfNotPresent
......
3.7 升级策略
[root@clientvm ~]# kubectl explain deployment.spec.strategy.rollingUpdate
KIND: Deployment
VERSION: apps/v1
RESOURCE: rollingUpdate <Object>
DESCRIPTION:
Rolling update config params. Present only if DeploymentStrategyType =
RollingUpdate.
Spec to control the desired behavior of rolling update.
FIELDS:
maxSurge <string>
The maximum number of pods that can be scheduled above the desired number
of pods. Value can be an absolute number (ex: 5) or a percentage of desired
pods (ex: 10%). This can not be 0 if MaxUnavailable is 0. Absolute number
is calculated from percentage by rounding up. Defaults to 25%. Example:
when this is set to 30%, the new ReplicaSet can be scaled up immediately
when the rolling update starts, such that the total number of old and new
pods do not exceed 130% of desired pods. Once old pods have been killed,
new ReplicaSet can be scaled up further, ensuring that total number of pods
running at any time during the update is at most 130% of desired pods.
maxUnavailable <string>
The maximum number of pods that can be unavailable during the update. Value
can be an absolute number (ex: 5) or a percentage of desired pods (ex:
10%). Absolute number is calculated from percentage by rounding down. This
can not be 0 if MaxSurge is 0. Defaults to 25%. Example: when this is set
to 30%, the old ReplicaSet can be scaled down to 70% of desired pods
immediately when the rolling update starts. Once new pods are ready, old
ReplicaSet can be scaled down further, followed by scaling up the new
ReplicaSet, ensuring that the total number of pods available at all times
during the update is at least 70% of desired pods.
- MaxUnavailable：滚动过程中最多有多少个 Pod 不可用；
- MaxSurge：滚动过程中最多存在多少个 Pod 超过预期 replicas 数量。
3.8 其他操作
[root@clientvm ~]# kubectl rollout -h
Manage the rollout of a resource.
Available Commands:
history View rollout history
pause Mark the provided resource as paused
restart Restart a resource
resume Resume a paused resource
status Show the status of the rollout
undo Undo a previous rollout
3.9 删除Deployment
[root@clientvm ~]# kubectl delete -f dep-from-file.yaml
deployment.apps "dep-from-file" deleted
[root@clientvm ~]# kubectl get deployments.apps -n mytest
NAME READY UP-TO-DATE AVAILABLE AGE
testdep 2/2 2 2 129m
若有收获，就点个赞吧
0 人点赞
