K8S之资源控制器RC、RS、Deployment详解
1. （Controller）-Deployment
1.1. 介绍
kubernetes中内建了很多controller（控制器），这些相当于一个状态机，用来控制pod的具体状态和行为。
Controller，在集群上管理和运行容器的对象。
- 确保预期的Pod副本数量
- 无状态应用部署
- 有状态应用部署
- 确保所有的node运行同一个pod
- 一次性任务和定时任务
部分控制器类型如下：
- ReplicationController 和 ReplicaSet
- Deployment
- DaemonSet
- StatefulSet
- Job/CronJob
- HorizontalPodAutoscaler
1. 简介
Pod控制器有很多种，最初的是使用 ReplicationController，即副本控制器，用于控制pod数量。随着版本升级，出现了ReplicaSet，跟ReplicationController没有本质的不同，只是名字不一样，并且ReplicaSet支持集合式的selector。ReplicaSet的核心管理对象有三种：用户期望的副本数、标签选择器、pod模板。
ReplicaSet一般不会直接使用，而是采用Deployment，Deployment是用来管理Replicaset，ReplicaSet来管理Pod。Deployment为ReplicaSet 提供了一个声明式定义(declarative)方法，用来替代以前的 ReplicationController 来方便的管理应用，比ReplicaSet的功能更加强大，且包含了ReplicaSet的功能。Deployment支持以下功能：
- 定义Deployment来创建Pod和ReplicaSet
- 滚动升级和回滚应用
- 扩容和缩容
- 暂停部署功能和手动部署
2. 部署方式
- 蓝绿发布
如图，假设副本数是5，目标是从v1升级到v2。先部署5个v2版本的业务机器，再将SLB的流量全部切换到v2上。如果出现异常，可以快速切换到v1版本。但是实际上用的不多，因为需要消耗大量的额外机器资源。
- 滚动发布
滚动发布是逐台(批次)升级，需要占用的额外资源少。比如先升级一台，再升级一台，直到全部升级完毕。也可以每次升级10%数量的机器，逐批次升级。
- 灰度发布(金丝雀发布)
灰度发布也叫金丝雀发布，起源是，矿井工人发现，金丝雀对瓦斯气体很敏感，矿工会在下井之前，先放一只金丝雀到井中，如果金丝雀不叫了，就代表瓦斯浓度高。
灰度发布会先升级一台灰度机器，将版本升级为v2，此时先经过测试验证，确认没有问题后。从LB引入少量流量进入灰度机器，运行一段时间后，再将其它机器升级为v2版本，引入全部流量。
3. Deployment升级方案
Deployment的升级方案默认是滚动升级，支持升级暂停，支持指定最大超过预期pod数量，支持指定最小低于预期pod数量。可以实现上述三种部署方案(以目标预期pod数量5个，v1版本升级到v2版本为案例)：
- 蓝绿发布场景实现方案：新创建5个v2版本pod，等待5个v2版本Pod就绪后，下掉5个v1版本pod。
- 灰度发布场景实现案例：新创建的第一个pod最为灰度pod，此时暂定升级，等待灰度成功后再升级v1版本Pod
- 滚动发布：通过控制超出预期pod数量和低于预期Pod数量来控制滚动发布的节奏。
如下图，预期pod数量5个，滚动升级，最大超出副本数为2个，最大低于期望值2个的升级方式：
1.2. 模板
apiVersion: apps/v1
kind: Deployment
metadata
name <string> # 在一个名称空间不能重复
namespace <string> # 指定名称空间，默认defalut
labels <map[string]string> # 标签
annotations <map[string]string> # 注释
apiVersion: apps/v1
kind: Deployment
metadata
name <string> # 在一个名称空间不能重复
namespace <string> # 指定名称空间，默认defalut
labels <map[string]string> # 标签
annotations <map[string]string> # 注释
spec
replicas <integer> # 期望副本数，默认值1
selector <Object> # 标签选择器
matchExpressions <[]Object> # 标签选择器的一种形式,多个条件使用AND连接
key <string> -required- # 标签中的Key
operator <string> -required- # 操作符，支持 In, NotIn, Exists, DoesNotExist
values <[]string> # value的数组集合，当操作符为In或NotIn时不能为空
matchLabels <map[string]string> # 使用key/value的格式做筛选
strategy <Object> # pod更新策略，即如何替换已有的pod
type <string> # 更新类型，支持 Recreate, RollingUpdate。默认RollingUpdate
rollingUpdate <Object> # 滚动更新策略，仅在type为RollingUpdate时使用
maxSurge <string> # 最大浪涌pod数，即滚动更新时最多可多于出期望值几个pod。支持数字和百分比格式
maxUnavailable <string> # 最大缺失Pod数，即滚动更新时最多可少于期望值出几个pod。支持数字和百分比格式
revisionHistoryLimit <integer> # 历史版本记录数，默认为最大值(2^32)
template <Object> -required- # Pod模板，和Pod管理器yaml几乎格式一致
metadata <Object> # Pod的metadata
spec <Object> # Pod的spec
1.3 Pod和Controller关系
- Pod是通过Controller实现应用的运维，比如伸缩，滚动升级等。
- Pod和Controller之间通过label标签建立关系
Deployment 控制器为 Pods和 ReplicaSets提供描述性的更新方式。用来替代以前的ReplicationController以方便管理应用。
典型的应用场景包括：
-
定义Deployment来创建Pod和ReplicaSet
-
滚动升级和回滚应用
-
扩容和缩容，管理Pod和ReplicaSet（副本数量）
-
暂停和继续Deployment
-
部署无状态应用（Web，微服务，nginx等）
2.1 yaml文件字段说明
[外链图片转存失败,源站可能有防盗链机制,建议将图片保存下来直接上传(img-KfX30Wxu-1607492356983)(…\img\yaml2.png)]
2.2 Deployment控制器应用部署
# 1.生成yaml文件到Web.yaml，导出yaml文件
kubectl create deployment web --image=nginx --dry-run -o yaml > web.yaml
部署：
# 2.使用yaml部署应用
kubectl apply -f web.yaml
# 3.查看
kubectl get pods
# 4.对外发布（暴露对外端口号）-----先生成yaml文件
kubectl expose deployment web --port=80 --type=NodePort --target-port=80 --name=web1 -o yaml >
web1.yaml
# 5. 使用yaml方式发布
kubectl apply -f web1.yaml
# 6、查看已经发布的应用
kubectl get pods,svc
2.3 ReplicaSet示例
yaml文件
[root@k8s-master controller]# pwd
/root/k8s_practice/controller
[root@k8s-master controller]# cat ReplicaSet-01.yaml
apiVersion: apps/v1
kind: ReplicaSet
metadata:
name: frontend
spec:
replicas: 3
selector:
matchLabels:
tier: frontend
template:
metadata:
labels:
tier: frontend
spec:
containers:
- name: nginx
image: registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17
imagePullPolicy: IfNotPresent
ports:
- name: httpd
containerPort: 80
创建ReplicaSet，并查看rs状态与详情
[root@k8s-master controller]# kubectl apply -f ReplicaSet-01.yaml
replicaset.apps/frontend created
[root@k8s-master controller]# kubectl get rs -o wide # 查看状态
NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR
frontend 3 3 3 2m12s nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17 tier=frontend
[root@k8s-master controller]#
[root@k8s-master controller]# kubectl describe rs frontend # 查看详情
Name: frontend
Namespace: default
Selector: tier=frontend
Labels: <none>
Annotations: kubectl.kubernetes.io/last-applied-configuration:
{"apiVersion":"apps/v1","kind":"ReplicaSet","metadata":{"annotations":{},"name":"frontend","namespace":"default"},"spec":{"replicas":3,"se...
Replicas: 3 current / 3 desired
Pods Status: 3 Running / 0 Waiting / 0 Succeeded / 0 Failed
Pod Template:
Labels: tier=frontend
Containers:
nginx:
Image: registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17
Port: 80/TCP
Host Port: 0/TCP
Environment: <none>
Mounts: <none>
Volumes: <none>
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal SuccessfulCreate 10m replicaset-controller Created pod: frontend-kltwp
Normal SuccessfulCreate 10m replicaset-controller Created pod: frontend-76dbn
Normal SuccessfulCreate 10m replicaset-controller Created pod: frontend-jk8td
查看pod状态信息
[root@k8s-master controller]# kubectl get pod -o wide --show-labels
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES LABELS
frontend-76dbn 1/1 Running 0 5m15s 10.244.4.31 k8s-node01 <none> <none> tier=frontend
frontend-jk8td 1/1 Running 0 5m15s 10.244.2.35 k8s-node02 <none> <none> tier=frontend
frontend-kltwp 1/1 Running 0 5m15s 10.244.2.34 k8s-node02 <none> <none> tier=frontend
删除一个pod，然后再次查看
[root@k8s-master controller]# kubectl delete pod frontend-kltwp
pod "frontend-kltwp" deleted
[root@k8s-master controller]#
[root@k8s-master controller]# kubectl get pod -o wide --show-labels # 可见重新创建了一个pod
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES LABELS
frontend-76dbn 1/1 Running 0 7m27s 10.244.4.31 k8s-node01 <none> <none> tier=frontend
frontend-jk8td 1/1 Running 0 7m27s 10.244.2.35 k8s-node02 <none> <none> tier=frontend
frontend-mf79k 1/1 Running 0 16s 10.244.4.32 k8s-node01 <none> <none> tier=frontend
由上可见，rs又新建了一个pod，保证了pod数总是为3.
2.4 Deployment示例
创建 Deployment
yaml文件
[root@k8s-master controller]# pwd
/root/k8s_practice/controller
[root@k8s-master controller]# cat nginx-deployment-1.17.1.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: nginx
spec:
replicas: 3
# 重点关注该字段
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.1
ports:
- containerPort: 80
[root@k8s-master controller]#
[root@k8s-master controller]# cat nginx-deployment-1.17.5.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: nginx
spec:
replicas: 3
# 重点关注该字段
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5
ports:
- containerPort: 80
selector 字段定义 Deployment 如何查找要管理的 Pods。 在这种情况下，会选择在 template（Pod）模板中定义的标签labels（app: nginx）。但更复杂的选择规则是可能的，只要 template （Pod） 模板本身满足规则。
刚启动时状态说明
启动deployment，并查看状态
[root@k8s-master controller]# kubectl apply -f nginx-deployment-1.17.1.yaml --record
deployment.apps/nginx-deployment created
[root@k8s-master controller]#
[root@k8s-master controller]# kubectl get deployment -o wide
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
nginx-deployment 2/3 3 2 10s nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.1 app=nginx
# --record 参数可以记录命令，通过 kubectl rollout history deployment/nginx-deployment 可查询
参数说明：
- NAME：列出集群中 Deployments 的名称
- READY：已就绪副本数/期望副本数
- UP-TO-DATE：显示已更新和正在更新中的副本数
- AVAILABLE：显示应用程序可供用户使用的副本数
- AGE：显示运行的时间
查看ReplicaSet状态
[root@k8s-master controller]# kubectl get rs -o wide
NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR
nginx-deployment-76b9d6bcf5 3 3 2 17s nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.1 app=nginx,pod-template-hash=76b9d6bcf5
参数说明：
- NAME：列出集群中 ReplicaSet的名称
- DESIRED：期望副本数
- CURRENT：当前副本数
- READY：已就绪副本数
- AGE：运行时间
查看pod状态
[root@k8s-master controller]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-deployment-76b9d6bcf5-ngpg5 1/1 Running 0 26s 10.244.2.43 k8s-node02 <none> <none>
nginx-deployment-76b9d6bcf5-rw827 1/1 Running 0 26s 10.244.2.44 k8s-node02 <none> <none>
nginx-deployment-76b9d6bcf5-ttf4j 0/1 ContainerCreating 0 26s <none> k8s-node01 <none> <none>
过一会儿状态说明
[root@k8s-master controller]# kubectl get deployment -o wide --show-labels
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR LABELS
nginx-deployment 3/3 3 3 23m nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.1 app=nginx app=nginx
[root@k8s-master controller]#
[root@k8s-master controller]# kubectl get rs -o wide --show-labels
NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR LABELS
nginx-deployment-76b9d6bcf5 3 3 3 23m nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.1 app=nginx,pod-template-hash=76b9d6bcf5 app=nginx,pod-template-hash=76b9d6bcf5
[root@k8s-master controller]#
[root@k8s-master controller]# kubectl get pod -o wide --show-labels
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES LABELS
nginx-deployment-76b9d6bcf5-ngpg5 1/1 Running 0 23m 10.244.2.43 k8s-node02 <none> <none> app=nginx,pod-template-hash=76b9d6bcf5
nginx-deployment-76b9d6bcf5-rw827 1/1 Running 0 23m 10.244.2.44 k8s-node02 <none> <none> app=nginx,pod-template-hash=76b9d6bcf5
nginx-deployment-76b9d6bcf5-ttf4j 1/1 Running 0 23m 10.244.4.37 k8s-node01 <none> <none> app=nginx,pod-template-hash=76b9d6bcf5
重点说明
1、ReplicaSet 的名称始终被格式化为[DEPLOYMENT-NAME]-[RANDOM-STRING]。随机字符串是随机生成，并使用 pod-template-hash 作为选择器和标签。
2、Deployment 控制器将 pod-template-hash 标签添加到 Deployment 创建或使用的每个 ReplicaSet 。此标签可确保 Deployment 的子 ReplicaSets 不重叠。因此不可修改。
3、注意Deployment、ReplicaSet和Pod三者的名称关系
2.5 更新 Deployment
Deployment 可确保在更新时仅关闭一定数量的 Pods。默认情况下，它确保至少 75%所需 Pods 运行（25%最大不可用）。
Deployment 更新过程中还确保仅创建一定数量的 Pods 且高于期望的 Pods 数。默认情况下，它可确保最多增加 25% 期望 Pods 数（25%最大增量）。
备注：实际操作中如果更新Deployment，那么最好通过yaml文件更新，这样回滚到任何版本都非常便捷，而且更容易追述；而不是通过命令行。
如下Deployment示例，由于只有3个副本。因此更新时不会先删除旧的pod，而是先新建一个pod。新pod运行时，才会删除对应老的pod。一切的前提都是为了满足上述的条件。
需求：更新 nginx Pods，从当前的1.17.1版本改为1.17.5版本。
# 方式一
kubectl edit deployment/nginx-deployment # 然后修改 image 镜像信息 【不推荐】
# 上述方法不会记录命令，通过kubectl rollout history deployment/nginx-deployment 无法查询
# 方式二如下【可使用】：
kubectl set image deployment/nginx-deployment nginx=registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5 --record
# 方式三如下【推荐★★★★★】
kubectl apply -f nginx-deployment-1.17.5.yaml --record
# --record 参数可以记录命令，通过 kubectl rollout history deployment/nginx-deployment 可查询
要查看更新状态
[root@k8s-master controller]# kubectl rollout status deployment/nginx-deployment
# 如没有更新完成，则显示更新过程直到更新成功
Waiting for deployment "nginx-deployment" rollout to finish: 1 out of 3 new replicas have been updated...
Waiting for deployment "nginx-deployment" rollout to finish: 1 out of 3 new replicas have been updated...
Waiting for deployment "nginx-deployment" rollout to finish: 2 out of 3 new replicas have been updated...
Waiting for deployment "nginx-deployment" rollout to finish: 2 out of 3 new replicas have been updated...
Waiting for deployment "nginx-deployment" rollout to finish: 2 out of 3 new replicas have been updated...
Waiting for deployment "nginx-deployment" rollout to finish: 1 old replicas are pending termination...
Waiting for deployment "nginx-deployment" rollout to finish: 1 old replicas are pending termination...
deployment "nginx-deployment" successfully rolled out
# 如已更新完毕，直接显示更新成功
deployment "nginx-deployment" successfully rolled out
更新中的Deployment、ReplicaSet、Pod信息
[root@k8s-master controller]# kubectl get deployment -o wide --show-labels
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR LABELS
nginx-deployment 3/3 1 3 12m nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5 app=nginx app=nginx
[root@k8s-master controller]#
[root@k8s-master controller]# kubectl get rs -o wide --show-labels
NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR LABELS
nginx-deployment-56d78686f5 1 1 0 23s nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5 app=nginx,pod-template-hash=56d78686f5 app=nginx,pod-template-hash=56d78686f5
nginx-deployment-76b9d6bcf5 3 3 3 12m nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.1 app=nginx,pod-template-hash=76b9d6bcf5 app=nginx,pod-template-hash=76b9d6bcf5
[root@k8s-master controller]#
[root@k8s-master controller]# kubectl get pod -o wide --show-labels
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES LABELS
nginx-deployment-56d78686f5-4kn4c 0/1 ContainerCreating 0 30s <none> k8s-node02 <none> <none> app=nginx,pod-template-hash=56d78686f5
nginx-deployment-76b9d6bcf5-7lcr9 1/1 Running 0 12m 10.244.4.41 k8s-node01 <none> <none> app=nginx,pod-template-hash=76b9d6bcf5
nginx-deployment-76b9d6bcf5-jbb5h 1/1 Running 0 12m 10.244.2.48 k8s-node02 <none> <none> app=nginx,pod-template-hash=76b9d6bcf5
nginx-deployment-76b9d6bcf5-rt4m7 1/1 Running 0 12m 10.244.4.42 k8s-node01 <none> <none> app=nginx,pod-template-hash=76b9d6bcf5
更新成功后的Deployment、ReplicaSet、Pod信息
[root@k8s-master controller]# kubectl get deployment -o wide --show-labels
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR LABELS
nginx-deployment 3/3 3 3 15m nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5 app=nginx app=nginx
[root@k8s-master controller]#
[root@k8s-master controller]# kubectl get rs -o wide --show-labels
NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR LABELS
nginx-deployment-56d78686f5 3 3 3 3m23s nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5 app=nginx,pod-template-hash=56d78686f5 app=nginx,pod-template-hash=56d78686f5
nginx-deployment-76b9d6bcf5 0 0 0 15m nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.1 app=nginx,pod-template-hash=76b9d6bcf5 app=nginx,pod-template-hash=76b9d6bcf5
[root@k8s-master controller]#
[root@k8s-master controller]# kubectl get pod -o wide --show-labels
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES LABELS
nginx-deployment-56d78686f5-4kn4c 1/1 Running 0 3m25s 10.244.2.49 k8s-node02 <none> <none> app=nginx,pod-template-hash=56d78686f5
nginx-deployment-56d78686f5-khsnm 1/1 Running 0 100s 10.244.2.50 k8s-node02 <none> <none> app=nginx,pod-template-hash=56d78686f5
nginx-deployment-56d78686f5-t24qw 1/1 Running 0 2m44s 10.244.4.43 k8s-node01 <none> <none> app=nginx,pod-template-hash=56d78686f5
通过查询Deployment详情，知晓pod替换过程
[root@k8s-master controller]# kubectl describe deploy nginx-deployment
Name: nginx-deployment
Namespace: default
CreationTimestamp: Thu, 28 May 2020 00:04:09 +0800
Labels: app=nginx
Annotations: deployment.kubernetes.io/revision: 2
kubectl.kubernetes.io/last-applied-configuration:
{"apiVersion":"apps/v1","kind":"Deployment","metadata":{"annotations":{"kubernetes.io/change-cause":"kubectl apply --filename=nginx-deploy...
kubernetes.io/change-cause:
kubectl set image deployment/nginx-deployment nginx=registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5 --record=true
Selector: app=nginx
Replicas: 3 desired | 3 updated | 3 total | 3 available | 0 unavailable
StrategyType: RollingUpdate
MinReadySeconds: 0
RollingUpdateStrategy: 25% max unavailable, 25% max surge
Pod Template:
Labels: app=nginx
Containers:
nginx:
Image: registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5
Port: 80/TCP
Host Port: 0/TCP
Environment: <none>
Mounts: <none>
Volumes: <none>
Conditions:
Type Status Reason
---- ------ ------
Available True MinimumReplicasAvailable
Progressing True NewReplicaSetAvailable
OldReplicaSets: <none>
NewReplicaSet: nginx-deployment-56d78686f5 (3/3 replicas created)
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal ScalingReplicaSet 93s deployment-controller Scaled up replica set nginx-deployment-76b9d6bcf5 to 3
Normal ScalingReplicaSet 38s deployment-controller Scaled up replica set nginx-deployment-56d78686f5 to 1
Normal ScalingReplicaSet 37s deployment-controller Scaled down replica set nginx-deployment-76b9d6bcf5 to 2
Normal ScalingReplicaSet 37s deployment-controller Scaled up replica set nginx-deployment-56d78686f5 to 2
Normal ScalingReplicaSet 35s deployment-controller Scaled down replica set nginx-deployment-76b9d6bcf5 to 1
Normal ScalingReplicaSet 35s deployment-controller Scaled up replica set nginx-deployment-56d78686f5 to 3
Normal ScalingReplicaSet 34s deployment-controller Scaled down replica set nginx-deployment-76b9d6bcf5 to 0
2.6 多 Deployment 动态更新
当 Deployment 正在展开进行更新时，Deployment 会为每个更新创建一个新的 ReplicaSet 并开始向上扩展，之前的 ReplicaSet 会被添加到旧 ReplicaSets 队列并开始向下扩展。
例如，假设创建一个 Deployment 以创建 nginx:1.7.9 的 5 个副本，然后更新 Deployment 以创建 5 个 nginx:1.9.1 的副本，而此时只有 3 个nginx:1.7.9 的副本已创建。在这种情况下， Deployment 会立即开始杀死3个 nginx:1.7.9 Pods，并开始创建 nginx:1.9.1 Pods。它不等待 nginx:1.7.9 的 5 个副本完成后再更新为nginx:1.9.1。
回滚 Deployment
yaml文件方式
针对应用的每个镜像版本，都有对应deploy的yaml文件。不管是升级还是回滚都已轻松应对。如下
nginx-deployment-1.15.6.yaml
nginx-deployment-1.17.yaml
nginx-deployment-1.17.1.yaml
nginx-deployment-1.17.5.yaml
yaml文件中的信息，参考上文即可。
命令行方式
问题产生
假设在更新 Deployment 时犯了一个拼写错误，将镜像名称命名为了 nginx:1.1710 而不是 nginx:1.17.10
[root@k8s-master controller]# kubectl set image deployment/nginx-deployment nginx=registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.1710 --record
deployment.apps/nginx-deployment image updated
查看Deployment、ReplicaSet、Pod信息
[root@k8s-master controller]# kubectl get deploy -o wide --show-labels
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR LABELS
nginx-deployment 3/3 1 3 14m nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.1710 app=nginx app=nginx
[root@k8s-master controller]#
[root@k8s-master controller]# kubectl get rs -o wide --show-labels
NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR LABELS
nginx-deployment-55c7bdfb86 3 3 3 9m19s nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17 app=nginx,pod-template-hash=55c7bdfb86 app=nginx,pod-template-hash=55c7bdfb86
nginx-deployment-56d78686f5 0 0 0 12m nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5 app=nginx,pod-template-hash=56d78686f5 app=nginx,pod-template-hash=56d78686f5
nginx-deployment-76b9d6bcf5 0 0 0 13m nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.1 app=nginx,pod-template-hash=76b9d6bcf5 app=nginx,pod-template-hash=76b9d6bcf5
nginx-deployment-844d7bbb7f 1 1 0 64s nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.1710 app=nginx,pod-template-hash=844d7bbb7f app=nginx,pod-template-hash=844d7bbb7f
[root@k8s-master controller]#
[root@k8s-master controller]# kubectl get pod -o wide --show-labels
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES LABELS
nginx-deployment-55c7bdfb86-bwzk9 1/1 Running 0 10m 10.244.4.49 k8s-node01 <none> <none> app=nginx,pod-template-hash=55c7bdfb86
nginx-deployment-55c7bdfb86-cmvzg 1/1 Running 0 10m 10.244.2.55 k8s-node02 <none> <none> app=nginx,pod-template-hash=55c7bdfb86
nginx-deployment-55c7bdfb86-kjrrw 1/1 Running 0 10m 10.244.2.56 k8s-node02 <none> <none> app=nginx,pod-template-hash=55c7bdfb86
nginx-deployment-844d7bbb7f-pctwr 0/1 ImagePullBackOff 0 2m3s 10.244.4.51 k8s-node01 <none> <none> app=nginx,pod-template-hash=844d7bbb7f
需求：回滚到以前稳定的 Deployment 版本。
操作步骤如下：
检查 Deployment 修改历史
[root@k8s-master controller]# kubectl rollout history deployment/nginx-deployment
deployment.apps/nginx-deployment
REVISION CHANGE-CAUSE
1 kubectl apply --filename=nginx-deployment.yaml --record=true
2 kubectl set image deployment/nginx-deployment nginx=registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5 --record=true
3 kubectl set image deployment/nginx-deployment nginx=registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17 --record=true
4 kubectl set image deployment/nginx-deployment nginx=registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.1710 --record=true
查看修改历史的详细信息，运行
[root@k8s-master controller]# kubectl rollout history deployment/nginx-deployment --revision=3
deployment.apps/nginx-deployment with revision #3
Pod Template:
Labels: app=nginx
pod-template-hash=55c7bdfb86
Annotations: kubernetes.io/change-cause:
kubectl set image deployment/nginx-deployment nginx=registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17 --record=true
Containers:
nginx:
Image: registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17
Port: 80/TCP
Host Port: 0/TCP
Environment: <none>
Mounts: <none>
Volumes: <none>
回滚到上一次修改（即版本 3）或指定版本
现在已决定撤消当前更新并回滚到以前的版本
# 回滚到上一版本
[root@k8s-master controller]# kubectl rollout undo deployment/nginx-deployment
deployment.apps/nginx-deployment rolled back
# 回滚到指定历史版本
[root@k8s-master controller]# kubectl rollout undo deployment/nginx-deployment --to-revision=2
deployment.apps/nginx-deployment rolled back
检查回滚是否成功、 Deployment 是否正在运行
[root@k8s-master controller]# kubectl get deploy -o wide --show-labels
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR LABELS
nginx-deployment 3/3 3 3 17h nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5 app=nginx app=nginx
获取 Deployment 描述信息
[root@k8s-master controller]# kubectl describe deployment
Name: nginx-deployment
Namespace: default
CreationTimestamp: Thu, 28 May 2020 00:04:09 +0800
Labels: app=nginx
Annotations: deployment.kubernetes.io/revision: 7
kubectl.kubernetes.io/last-applied-configuration:
{"apiVersion":"apps/v1","kind":"Deployment","metadata":{"annotations":{"kubernetes.io/change-cause":"kubectl apply --filename=nginx-deploy...
kubernetes.io/change-cause:
kubectl set image deployment/nginx-deployment nginx=registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5 --record=true
Selector: app=nginx
Replicas: 3 desired | 3 updated | 3 total | 3 available | 0 unavailable
StrategyType: RollingUpdate
MinReadySeconds: 0
RollingUpdateStrategy: 25% max unavailable, 25% max surge
Pod Template:
Labels: app=nginx
Containers:
nginx:
Image: registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5
Port: 80/TCP
Host Port: 0/TCP
Environment: <none>
Mounts: <none>
Volumes: <none>
Conditions:
Type Status Reason
---- ------ ------
Available True MinimumReplicasAvailable
Progressing True NewReplicaSetAvailable
OldReplicaSets: <none>
NewReplicaSet: nginx-deployment-56d78686f5 (3/3 replicas created)
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
………………
Normal ScalingReplicaSet 107s deployment-controller Scaled up replica set nginx-deployment-56d78686f5 to 1
Normal ScalingReplicaSet 104s deployment-controller Scaled down replica set nginx-deployment-55c7bdfb86 to 2
Normal ScalingReplicaSet 104s deployment-controller Scaled up replica set nginx-deployment-56d78686f5 to 2
Normal ScalingReplicaSet 103s deployment-controller Scaled down replica set nginx-deployment-55c7bdfb86 to 1
Normal ScalingReplicaSet 103s deployment-controller Scaled up replica set nginx-deployment-56d78686f5 to 3
Normal ScalingReplicaSet 102s deployment-controller Scaled down replica set nginx-deployment-55c7bdfb86 to 0
2.7 扩容/缩容Deployment
操作过程如下
[root@k8s-master controller]# kubectl scale deployment/nginx-deployment --replicas=10
deployment.apps/nginx-deployment scaled
[root@k8s-master controller]# kubectl get deploy -o wide --show-labels
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR LABELS
nginx-deployment 10/10 10 10 17h nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5 app=nginx app=nginx
[root@k8s-master controller]#
[root@k8s-master controller]# kubectl get rs -o wide --show-labels
NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR LABELS
nginx-deployment-55c7bdfb86 0 0 0 17h nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17 app=nginx,pod-template-hash=55c7bdfb86 app=nginx,pod-template-hash=55c7bdfb86
nginx-deployment-56d78686f5 10 10 10 17h nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.5 app=nginx,pod-template-hash=56d78686f5 app=nginx,pod-template-hash=56d78686f5
nginx-deployment-76b9d6bcf5 0 0 0 17h nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.17.1 app=nginx,pod-template-hash=76b9d6bcf5 app=nginx,pod-template-hash=76b9d6bcf5
nginx-deployment-844d7bbb7f 0 0 0 17h nginx registry.cn-beijing.aliyuncs.com/google_registry/nginx:1.1710 app=nginx,pod-template-hash=844d7bbb7f app=nginx,pod-template-hash=844d7bbb7f
[root@k8s-master controller]#
[root@k8s-master controller]# kubectl get pod -o wide --show-labels
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES LABELS
nginx-deployment-56d78686f5-4v5mj 1/1 Running 0 44s 10.244.2.64 k8s-node02 <none> <none> app=nginx,pod-template-hash=56d78686f5
nginx-deployment-56d78686f5-8m7mx 1/1 Running 0 44s 10.244.4.60 k8s-node01 <none> <none> app=nginx,pod-template-hash=56d78686f5
nginx-deployment-56d78686f5-c7wlb 1/1 Running 0 44s 10.244.4.59 k8s-node01 <none> <none> app=nginx,pod-template-hash=56d78686f5
nginx-deployment-56d78686f5-jg5lt 1/1 Running 0 44s 10.244.2.63 k8s-node02 <none> <none> app=nginx,pod-template-hash=56d78686f5
nginx-deployment-56d78686f5-jj58d 1/1 Running 0 11m 10.244.4.56 k8s-node01 <none> <none> app=nginx,pod-template-hash=56d78686f5
nginx-deployment-56d78686f5-k2kts 1/1 Running 0 11m 10.244.4.57 k8s-node01 <none> <none> app=nginx,pod-template-hash=56d78686f5
nginx-deployment-56d78686f5-qltkv 1/1 Running 0 44s 10.244.2.61 k8s-node02 <none> <none> app=nginx,pod-template-hash=56d78686f5
nginx-deployment-56d78686f5-r7vmm 1/1 Running 0 11m 10.244.2.60 k8s-node02 <none> <none> app=nginx,pod-template-hash=56d78686f5
nginx-deployment-56d78686f5-rxlpm 1/1 Running 0 44s 10.244.2.62 k8s-node02 <none> <none> app=nginx,pod-template-hash=56d78686f5
nginx-deployment-56d78686f5-vlzrf 1/1 Running 0 44s 10.244.4.58 k8s-node01 <none> <none> app=nginx,pod-template-hash=56d78686f5
2.8 清理策略Policy
可以在 Deployment 中设置 .spec.revisionHistoryLimit，以指定保留多少该 Deployment 的 ReplicaSets数量。其余的将在后台进行垃圾回收。默认情况下，是10。
注意：此字段设置为 0 将导致清理 Deployment 的所有历史记录，因此 Deployment 将无法通过命令行回滚。
3、 升级回滚# 应用升级
kubectl set image deployment web nginx=nginx:1.15
# 查看升级状态
kubectl rollout status deployment web
# 查看升级的历史版本
kubectl rollout history deployment web
# 回滚，还原到上一个版本
kubectl rollout undo deployment web
# 回滚到指定的版本
kubectl rollout undo deployment web --to-version=2
# 弹性伸缩
kubectl scale deployment web --replicas=10
1. 创建deployment
[root@hdss7-200 deployment]# vim /data/k8s-yaml/base_resource/deployment/nginx-v1.12.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deploy
namespace: app
spec:
replicas: 5
selector:
matchLabels:
app: nginx
release: stable
tier: slb
partition: website
strategy:
rollingUpdate:
maxSurge: 1
maxUnavailable: 0
template:
metadata:
labels:
app: nginx
release: stable
tier: slb
partition: website
version: v1.12
spec:
containers:
- name: nginx-pod
image: harbor.od.com/public/nginx:v1.12
lifecycle:
postStart:
exec:
command:
- /bin/bash
- -c
- "echo 'health check ok!' > /usr/share/nginx/html/health.html"
readinessProbe:
initialDelaySeconds: 5
httpGet:
port: 80
path: /health.html
livenessProbe:
initialDelaySeconds: 10
periodSeconds: 5
httpGet:
port: 80
path: /health.html
[root@hdss7-21 ~]# kubectl apply -f http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.12.yaml --record
[root@hdss7-21 ~]# kubectl get pods -n app -l partition=website # 查看
NAME READY STATUS RESTARTS AGE
nginx-deploy-5597c8b45-425ms 1/1 Running 0 5m12s
nginx-deploy-5597c8b45-5p2rz 1/1 Running 0 9m34s
nginx-deploy-5597c8b45-dw7hd 1/1 Running 0 9m34s
nginx-deploy-5597c8b45-fg82k 1/1 Running 0 5m12s
nginx-deploy-5597c8b45-sfxmg 1/1 Running 0 9m34s
[root@hdss7-21 ~]# kubectl get rs -n app -l partition=website -o wide
NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR
nginx-deploy-5597c8b45 8 8 8 10m nginx-pod harbor.od.com/public/nginx:v1.12 app=nginx,partition=website,pod-template-hash=5597c8b45,release=stable,tier=slb
[root@hdss7-21 ~]# kubectl get deployment -n app -o wide
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
nginx-deploy 8/8 8 8 11m nginx-pod harbor.od.com/public/nginx:v1.12 app=nginx,partition=website,release=stable,tier=slb
2. 模拟蓝绿发布
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deploy
namespace: app
spec:
replicas: 5
selector:
matchLabels:
app: nginx
release: stable
tier: slb
partition: website
strategy:
rollingUpdate:
# 最大浪涌数量为5
maxSurge: 5
maxUnavailable: 0
template:
metadata:
labels:
app: nginx
release: stable
tier: slb
partition: website
# 修改版本信息，用于查看当前版本
version: v1.13
spec:
containers:
- name: nginx-pod
# 修改镜像
image: harbor.od.com/public/nginx:v1.13
lifecycle:
postStart:
exec:
command:
- /bin/bash
- -c
- "echo 'health check ok!' > /usr/share/nginx/html/health.html"
readinessProbe:
initialDelaySeconds: 5
httpGet:
port: 80
path: /health.html
livenessProbe:
initialDelaySeconds: 10
periodSeconds: 5
httpGet:
port: 80
path: /health.html
[root@hdss7-21 ~]# kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.13.yaml --record=true
[root@hdss7-21 ~]# kubectl rollout history deployment nginx-deploy -n app
REVISION CHANGE-CAUSE
1 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.12.yaml --record=true
2 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.13.yaml --record=true
[root@hdss7-21 ~]# kubectl get rs -n app -l tier=slb -L version # 多个ReplicaSet对应不同版本
NAME DESIRED CURRENT READY AGE VERSION
nginx-deploy-5597c8b45 0 0 0 10m v1.12
nginx-deploy-6bd88df699 5 5 5 9m31s v1.13
# 升级过程中的状态变化:
[root@hdss7-21 ~]# kubectl rollout status deployment nginx-deploy -n app
Waiting for deployment "nginx-deploy" rollout to finish: 5 old replicas are pending termination...
Waiting for deployment "nginx-deploy" rollout to finish: 5 old replicas are pending termination...
Waiting for deployment "nginx-deploy" rollout to finish: 5 old replicas are pending termination...
Waiting for deployment "nginx-deploy" rollout to finish: 4 old replicas are pending termination...
Waiting for deployment "nginx-deploy" rollout to finish: 4 old replicas are pending termination...
Waiting for deployment "nginx-deploy" rollout to finish: 4 old replicas are pending termination...
Waiting for deployment "nginx-deploy" rollout to finish: 3 old replicas are pending termination...
Waiting for deployment "nginx-deploy" rollout to finish: 3 old replicas are pending termination...
Waiting for deployment "nginx-deploy" rollout to finish: 3 old replicas are pending termination...
Waiting for deployment "nginx-deploy" rollout to finish: 2 old replicas are pending termination...
Waiting for deployment "nginx-deploy" rollout to finish: 2 old replicas are pending termination...
Waiting for deployment "nginx-deploy" rollout to finish: 2 old replicas are pending termination...
Waiting for deployment "nginx-deploy" rollout to finish: 1 old replicas are pending termination...
Waiting for deployment "nginx-deploy" rollout to finish: 1 old replicas are pending termination...
deployment "nginx-deploy" successfully rolled out
[root@hdss7-21 ~]# kubectl get pod -n app -l partition=website -L version -w
NAME READY STATUS RESTARTS AGE VERSION
nginx-deploy-5597c8b45-t5plt 1/1 Running 0 19s v1.12
nginx-deploy-5597c8b45-tcq69 1/1 Running 0 19s v1.12
nginx-deploy-5597c8b45-vdjxg 1/1 Running 0 19s v1.12
nginx-deploy-5597c8b45-vqn9x 1/1 Running 0 19s v1.12
nginx-deploy-5597c8b45-zl6qr 1/1 Running 0 19s v1.12
---- 立刻创建5个新版本pod，Pending调度中
nginx-deploy-6bd88df699-242fr 0/1 Pending 0 0s v1.13
nginx-deploy-6bd88df699-242fr 0/1 Pending 0 0s v1.13
nginx-deploy-6bd88df699-8pmdg 0/1 Pending 0 0s v1.13
nginx-deploy-6bd88df699-4kj8z 0/1 Pending 0 0s v1.13
nginx-deploy-6bd88df699-n7x6n 0/1 Pending 0 0s v1.13
nginx-deploy-6bd88df699-8pmdg 0/1 Pending 0 0s v1.13
nginx-deploy-6bd88df699-4kj8z 0/1 Pending 0 0s v1.13
nginx-deploy-6bd88df699-8j85n 0/1 Pending 0 0s v1.13
nginx-deploy-6bd88df699-n7x6n 0/1 Pending 0 0s v1.13
nginx-deploy-6bd88df699-8j85n 0/1 Pending 0 0s v1.13
---- 创建pod中
nginx-deploy-6bd88df699-242fr 0/1 ContainerCreating 0 0s v1.13
nginx-deploy-6bd88df699-8pmdg 0/1 ContainerCreating 0 0s v1.13
nginx-deploy-6bd88df699-4kj8z 0/1 ContainerCreating 0 0s v1.13
nginx-deploy-6bd88df699-n7x6n 0/1 ContainerCreating 0 0s v1.13
nginx-deploy-6bd88df699-8j85n 0/1 ContainerCreating 0 0s v1.13
---- 启动pod
nginx-deploy-6bd88df699-242fr 0/1 Running 0 1s v1.13
nginx-deploy-6bd88df699-8j85n 0/1 Running 0 1s v1.13
nginx-deploy-6bd88df699-4kj8z 0/1 Running 0 1s v1.13
nginx-deploy-6bd88df699-n7x6n 0/1 Running 0 1s v1.13
nginx-deploy-6bd88df699-8pmdg 0/1 Running 0 1s v1.13
---- Pod逐个就绪，且替换旧版本的pod
nginx-deploy-6bd88df699-242fr 1/1 Running 0 6s v1.13
nginx-deploy-5597c8b45-t5plt 1/1 Terminating 0 50s v1.12
nginx-deploy-6bd88df699-8j85n 1/1 Running 0 7s v1.13
nginx-deploy-5597c8b45-vdjxg 1/1 Terminating 0 51s v1.12
nginx-deploy-5597c8b45-t5plt 0/1 Terminating 0 51s v1.12
nginx-deploy-5597c8b45-t5plt 0/1 Terminating 0 51s v1.12
nginx-deploy-6bd88df699-4kj8z 1/1 Running 0 7s v1.13
nginx-deploy-5597c8b45-zl6qr 1/1 Terminating 0 51s v1.12
nginx-deploy-5597c8b45-vdjxg 0/1 Terminating 0 52s v1.12
nginx-deploy-5597c8b45-vdjxg 0/1 Terminating 0 52s v1.12
nginx-deploy-5597c8b45-zl6qr 0/1 Terminating 0 53s v1.12
nginx-deploy-5597c8b45-t5plt 0/1 Terminating 0 54s v1.12
nginx-deploy-5597c8b45-t5plt 0/1 Terminating 0 54s v1.12
nginx-deploy-5597c8b45-zl6qr 0/1 Terminating 0 56s v1.12
nginx-deploy-5597c8b45-zl6qr 0/1 Terminating 0 56s v1.12
nginx-deploy-6bd88df699-n7x6n 1/1 Running 0 13s v1.13
nginx-deploy-5597c8b45-tcq69 1/1 Terminating 0 57s v1.12
nginx-deploy-5597c8b45-tcq69 0/1 Terminating 0 58s v1.12
nginx-deploy-5597c8b45-tcq69 0/1 Terminating 0 59s v1.12
nginx-deploy-6bd88df699-8pmdg 1/1 Running 0 15s v1.13
nginx-deploy-5597c8b45-vqn9x 1/1 Terminating 0 59s v1.12
nginx-deploy-5597c8b45-vqn9x 0/1 Terminating 0 60s v1.12
nginx-deploy-5597c8b45-vqn9x 0/1 Terminating 0 61s v1.12
nginx-deploy-5597c8b45-vqn9x 0/1 Terminating 0 61s v1.12
nginx-deploy-5597c8b45-vdjxg 0/1 Terminating 0 64s v1.12
nginx-deploy-5597c8b45-vdjxg 0/1 Terminating 0 64s v1.12
nginx-deploy-5597c8b45-tcq69 0/1 Terminating 0 64s v1.12
nginx-deploy-5597c8b45-tcq69 0/1 Terminating 0 64s v1.12
3. 滚动发布
通过定义 maxsurge 和 maxUnavailable 来实现滚动升级的速度，滚动升级中，可以使用 kubectl rollout pause 来实现暂停。
[root@hdss7-200 deployment]# vim /data/k8s-yaml/base_resource/deployment/nginx-v1.14.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deploy
namespace: app
spec:
replicas: 5
selector:
matchLabels:
app: nginx
release: stable
tier: slb
partition: website
strategy:
rollingUpdate:
# 以下两项，控制升级速度
maxSurge: 1
maxUnavailable: 0
template:
metadata:
labels:
app: nginx
release: stable
tier: slb
partition: website
# 修改版本
version: v1.14
spec:
containers:
- name: nginx-pod
# 修改镜像版本
image: harbor.od.com/public/nginx:v1.14
lifecycle:
postStart:
exec:
command:
- /bin/bash
- -c
- "echo 'health check ok!' > /usr/share/nginx/html/health.html"
readinessProbe:
initialDelaySeconds: 5
httpGet:
port: 80
path: /health.html
livenessProbe:
initialDelaySeconds: 10
periodSeconds: 5
httpGet:
port: 80
path: /health.html
[root@hdss7-21 ~]# kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.14.yaml --record=true
[root@hdss7-21 ~]# kubectl get rs -n app -l tier=slb -L version # replicaset 数量增加
NAME DESIRED CURRENT READY AGE VERSION
nginx-deploy-5597c8b45 0 0 0 155m v1.12
nginx-deploy-6bd88df699 0 0 0 154m v1.13
nginx-deploy-7c5976dcd9 5 5 5 83s v1.14
[root@hdss7-21 ~]# kubectl rollout history deployment nginx-deploy -n app # 升级记录
REVISION CHANGE-CAUSE
1 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.12.yaml --record=true
2 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.13.yaml --record=true
3 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.14.yaml --record=true
[root@hdss7-21 ~]# kubectl get pod -n app -l partition=website -L version -w # 逐个滚动升级
NAME READY STATUS RESTARTS AGE VERSION
nginx-deploy-6bd88df699-242fr 1/1 Running 0 152m v1.13
nginx-deploy-6bd88df699-4kj8z 1/1 Running 0 152m v1.13
nginx-deploy-6bd88df699-8j85n 1/1 Running 0 152m v1.13
nginx-deploy-6bd88df699-8pmdg 1/1 Running 0 152m v1.13
nginx-deploy-6bd88df699-n7x6n 1/1 Running 0 152m v1.13
nginx-deploy-7c5976dcd9-ttlqx 0/1 Pending 0 0s v1.14
nginx-deploy-7c5976dcd9-ttlqx 0/1 Pending 0 0s v1.14
nginx-deploy-7c5976dcd9-ttlqx 0/1 ContainerCreating 0 0s v1.14
nginx-deploy-7c5976dcd9-ttlqx 0/1 Running 0 1s v1.14
nginx-deploy-7c5976dcd9-ttlqx 1/1 Running 0 9s v1.14
nginx-deploy-6bd88df699-8pmdg 1/1 Terminating 0 153m v1.13
......
4. 模拟灰度(金丝雀)发布
灰度发布在不同场景中实现方式不同，如果当前灰度机器仅对测试开放，可以定义一个新的deployment来配合service来实现。如果需要切入一部分随机真实用户的流量，可以将生产机器中一台机器作为灰度机器，通过灰度后再升级其它的机器。
# nginx-v1.15.yaml 与 nginx-v1.14.yaml 一致，仅仅修改了镜像文件
[root@hdss7-21 ~]# kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.15.yaml --record=true && kubectl rollout pause deployment nginx-deploy -n app
[root@hdss7-21 ~]# kubectl rollout history deployment nginx-deploy -n app
REVISION CHANGE-CAUSE
1 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.12.yaml --record=true
2 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.13.yaml --record=true
3 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.14.yaml --record=true
4 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.15.yaml --record=true
[root@hdss7-21 ~]# kubectl get rs -n app -l tier=slb -L version # 存在两个ReplicaSet对外提供服务
NAME DESIRED CURRENT READY AGE VERSION
nginx-deploy-5597c8b45 0 0 0 177m v1.12
nginx-deploy-6695fd9655 1 1 1 2m22s v1.15
nginx-deploy-6bd88df699 0 0 0 176m v1.13
nginx-deploy-7c5976dcd9 5 5 5 23m v1.14
[root@hdss7-21 ~]# kubectl get pod -n app -l partition=website -L version -w # 新*存
NAME READY STATUS RESTARTS AGE VERSION
nginx-deploy-6695fd9655-tcm76 1/1 Running 0 17s v1.15
nginx-deploy-7c5976dcd9-4tnv4 1/1 Running 0 21m v1.14
nginx-deploy-7c5976dcd9-bpjc2 1/1 Running 0 20m v1.14
nginx-deploy-7c5976dcd9-gv8qm 1/1 Running 0 20m v1.14
nginx-deploy-7c5976dcd9-ttlqx 1/1 Running 0 21m v1.14
nginx-deploy-7c5976dcd9-xq2qs 1/1 Running 0 21m v1.14
# 手动暂停
[root@hdss7-21 ~]# kubectl rollout resume deployment nginx-deploy -n app && kubectl rollout pause deployment nginx-deploy -n app
[root@hdss7-21 ~]# kubectl get pod -n app -l partition=website -L version -w
NAME READY STATUS RESTARTS AGE VERSION
nginx-deploy-6695fd9655-jmb94 1/1 Running 0 19s v1.15
nginx-deploy-6695fd9655-tcm76 1/1 Running 0 6m19s v1.15
nginx-deploy-7c5976dcd9-4tnv4 1/1 Running 0 27m v1.14
nginx-deploy-7c5976dcd9-gv8qm 1/1 Running 0 26m v1.14
nginx-deploy-7c5976dcd9-ttlqx 1/1 Running 0 27m v1.14
nginx-deploy-7c5976dcd9-xq2qs 1/1 Running 0 27m v1.14
# 升级剩余所有机器
[root@hdss7-21 ~]# kubectl rollout resume deployment nginx-deploy -n app
5. 版本回滚
当升级出现异常时，执行回滚即可。
[root@hdss7-21 ~]# kubectl rollout history deployment nginx-deploy -n app # 查看历史版本记录
deployment.extensions/nginx-deploy
REVISION CHANGE-CAUSE
1 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.12.yaml --record=true
2 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.13.yaml --record=true
3 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.14.yaml --record=true
4 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.15.yaml --record=true
[root@hdss7-21 ~]# kubectl rollout undo deployment nginx-deploy -n app
[root@hdss7-21 ~]# kubectl rollout history deployment nginx-deploy -n app # 版本3已经被版本5替代
deployment.extensions/nginx-deploy
REVISION CHANGE-CAUSE
1 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.12.yaml --record=true
2 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.13.yaml --record=true
4 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.15.yaml --record=true
5 kubectl apply --filename=http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.14.yaml --record=true
[root@hdss7-21 ~]# kubectl get pod -n app -l partition=website -L version
NAME READY STATUS RESTARTS AGE VERSION
nginx-deploy-7c5976dcd9-2kps8 1/1 Running 0 2m20s v1.14
nginx-deploy-7c5976dcd9-bqs28 1/1 Running 0 2m6s v1.14
nginx-deploy-7c5976dcd9-jdvps 1/1 Running 0 2m13s v1.14
nginx-deploy-7c5976dcd9-vs8l4 1/1 Running 0 116s v1.14
nginx-deploy-7c5976dcd9-z99mb 1/1 Running 0 101s v1.14
[root@hdss7-21 ~]# kubectl get rs -n app -l tier=slb -L version
NAME DESIRED CURRENT READY AGE VERSION
nginx-deploy-5597c8b45 0 0 0 3h7m v1.12
nginx-deploy-6695fd9655 0 0 0 12m v1.15
nginx-deploy-6bd88df699 0 0 0 3h7m v1.13
nginx-deploy-7c5976dcd9 5 5 5 34m v1.14
6. 常用命令
kubectl rollout status deployment nginx-deploy -n app # 查看版本升级过程
kubectl rollout history deployment nginx-deploy -n app # 查看版本升级历史
kubectl apply -f http://k8s-yaml.od.com/base_resource/deployment/nginx-v1.15.yaml --record=true # 升级且记录升级命令
kubectl rollout undo deployment nginx-deploy -n app # 回滚到上个版本
kubectl rollout undo deployment nginx-deploy --to-revision=3 -n app # 回滚到版本3