Kubernetes-Deployment
Deployment
用于部署无状态的服务，这个是最常用的控制器。一般用于管理维护企业内部无状态的微服务，比如configserver、zuul、springboot。可以管理多个副本的Pod，实现无缝迁移、自动扩容缩容、自动灾难恢复、一键回滚等功能。
命令创建Deployment
$ kubectl create deployment nginx --image=nginx1.20
deployment.apps/nginx created
从文件创建
$ cat >>nginx-deployment.yaml<<-EOF
apiVersion: apps/v1
kind: Deployment
metadata:
annotations:
deployment.kubernetes.io/revision: "1"
generation: 1
labels:
app: nginx
name: nginx
namespace: default
spec:
progressDeadlineSeconds: 600
replicas: 2 # 副本数
revisionHistoryLimit: 10 # 历史记录保留的个数
selector:
matchLabels:
app: nginx
strategy:
rollingUpdate:
maxSurge: 25%
maxUnavailable: 25%
type: RollingUpdate
template:
metadata:
creationTimestamp: null
labels:
app: nginx
spec:
containers:
- image: nginx:1.20
imagePullPolicy: Always
name: nginx
resources: {}
terminationMessagePath: /dev/termination-log
terminationMessagePolicy: File
dnsPolicy: ClusterFirst
restartPolicy: Always
schedulerName: default-scheduler
securityContext: {}
terminationGracePeriodSeconds: 30
EOF
$ kubectl get deployment -o wide
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
nginx 2/2 2 2 16m nginx1-20-5k2fk nginx:1.20 app=nginx
NAME：Deployment名称
READY：Pod的状态，已经Ready的个数
UP-TO-DATE：已经达到期望状态的被更新的副本数
AVAILABLE：已经可以用的副本数
AGE：显示应用程序运行的时间
CONTAINERS：容器名称
IMAGES：容器的镜像
SELECTOR：管理的Pod的标签
更新
$ kubectl set image deployment nginx nginx=nginx:1.19 --record
deployment.apps/nginx image updated
查看应用升级状态
$ kubectl rollout status deployment nginx
deployment "nginx" successfully rolled out
回滚
查看历史版本
$ kubectl rollout history deployment nginx
deployment.apps/nginx
REVISION CHANGE-CAUSE
1 <none>
2 kubectl set image deployment nginx nginx=nginx:1.20 --record=true
3 kubectl set image deployment nginx nginx=nginx:1.21 --record=true
回滚到上一个版本
$ kubectl rollout undo deployment nginx
deployment.apps/nginx rolled back
查看回滚状态
$ kubectl rollout status deployment nginx
Waiting for deployment "nginx" rollout to finish: 1 old replicas are pending termination...
Waiting for deployment "nginx" rollout to finish: 1 old replicas are pending termination...
deployment "nginx" successfully rolled out
查看历史记录
$ kubectl rollout history deployment nginx
deployment.apps/nginx
REVISION CHANGE-CAUSE
1 <none>
3 kubectl set image deployment nginx nginx=nginx:1.21 --record=true
4 kubectl set image deployment nginx nginx=nginx:1.20 --record=true
查看指定版本的详细信息
$ kubectl rollout history deployment nginx --revision=4
deployment.apps/nginx with revision #4
Pod Template:
Labels: app=nginx
pod-template-hash=7766cbf97c
Annotations: kubernetes.io/change-cause: kubectl set image deployment nginx nginx=nginx:1.20 --record=true
Containers:
nginx:
Image: nginx:1.20
Port: <none>
Host Port: <none>
Environment: <none>
Mounts: <none>
Volumes: <none>
回滚到指定版本
$ kubectl rollout undo deployment nginx --to-revision=3
deployment.apps/nginx rolled back
扩容缩容
将已存在的资源进行扩容
$ kubectl scale deployment nginx --replicas=3
deployment.apps/nginx scaled
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx-58f8c48d58-9j4kh 1/1 Running 0 3m55s
nginx-58f8c48d58-gsmm2 1/1 Running 0 3m36s
nginx-58f8c48d58-pffrw 0/1 ContainerCreating 0 17s
将已存在的资源进行缩容
$ kubectl scale deployment nginx --replicas=1
deployment.apps/nginx scaled
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx-58f8c48d58-9j4kh 1/1 Running 0 5m51s
nginx-58f8c48d58-gsmm2 1/1 Terminating 0 5m32s
nginx-58f8c48d58-pffrw 1/1 Terminating 0 2m13
更新暂停和恢复
暂停更新
$ kubectl rollout pause deployment nginx
deployment.apps/nginx paused
$ kubectl set image deployment nginx nginx=nginx:1.15 --record
deployment.apps/nginx image updated
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx-58f8c48d58-9j4kh 1/1 Running 0 10m
恢复更新
$ kubectl rollout resume deployment nginx
deployment.apps/nginx resumed
$ kubectl get rs
NAME DESIRED CURRENT READY AGE
nginx-5759cb8dcc 0 0 0 27m
nginx-58f8c48d58 1 1 1 25m
nginx-7766cbf97c 0 0 0 27m
nginx-8695495f75 1 1 0 20s # 20秒前创建了一个rs
apiVersion: apps/v1
kind: Deployment
metadata:
annotations:
deployment.kubernetes.io/revision: "6"
kubernetes.io/change-cause: kubectl set image deployment nginx nginx=nginx:1.15
--record=true
creationTimestamp: "2022-01-11T06:41:17Z"
generation: 11
labels:
app: nginx
name: nginx
namespace: default
resourceVersion: "105521"
uid: 661de325-16ff-4851-bbd2-bc56d5dae807
spec:
progressDeadlineSeconds: 600
replicas: 1
revisionHistoryLimit: 10
selector:
matchLabels:
app: nginx
strategy:
rollingUpdate:
maxSurge: 25%
maxUnavailable: 25%
type: RollingUpdate
template:
metadata:
creationTimestamp: null
labels:
app: nginx
spec:
containers:
- image: nginx:1.15
imagePullPolicy: Always
name: nginx
resources:
limits:
cpu: 200m
memory: 128Mi
requests:
cpu: 10m
memory: 16Mi
terminationMessagePath: /dev/termination-log
terminationMessagePolicy: File
dnsPolicy: ClusterFirst
restartPolicy: Always
schedulerName: default-scheduler
securityContext: {}
terminationGracePeriodSeconds: 30
.spec.revisionHistoryLimit: 10 //设置保留RS旧的revision的个数，设置为0，不保留历史数据。
.spec.minReadySeconds： //可选参数，指定新创建的Pod在没有任何容器崩溃的情况下视为Ready最小的秒数，默认为0，即一旦被创建就视为可用。滚动更新的策略：
.spec.strategy.type: 更新deployment的方式，默认是RollingUpdate
- RollingUpdate：滚动更新，可以指定maxSurge和maxUnavailable
** maxUnavailable：指定在回滚或更新最大不可用的Pod的数量，可选字段，默认25%，可以设置成数字或百分比，如果该值为0，那么maxSurge就不能为0
** maxSurge：可以超过期望值的最大Pod数，可选字段，默认为25%，可以设置成数字或百分比，如果该值为0，那么maxUnavailable就不能为0- Recreate：重建，先删除旧的Pod，再创建新的Pod
