K8s常见示例
作者：互联网
目录
手动调整pod数量
- 对yaml文件改replicas数量
- 在dashboard改deployment的pod值
- 通过kubectl scale命令
- 通过kubectl edit 编辑deployment
kubectl edit deployment danran-nginx-deployment -n danran
kubectl scale
kubectl scale 对运行在k8s 环境中的pod 数量进行扩容(增加)或缩容(减小)
当前pod数量
root@master1:~# kubectl get deployment -n danran
NAME READY UP-TO-DATE AVAILABLE AGE
danran-nginx-deployment 1/1 1 1 18h
danran-tomcat-app1-deployment-label 1/1 1 1 19h
执行扩容/缩容
root@master1:~# kubectl scale deployment/danran-nginx-deployment --replicas=2 -n danran
deployment.apps/danran-nginx-deployment scaled
验证手动扩容结果
root@master1:~# kubectl get deployment -n danran
NAME READY UP-TO-DATE AVAILABLE AGE
danran-nginx-deployment 2/2 2 2 18h
danran-tomcat-app1-deployment-label 1/1 1 1 19h
HPA自动伸缩pod数量
kubectl autoscale 自动控制在k8s集群中运行的pod数量(水平自动伸缩)，需要提前设置pod范围及触发条件
控制管理器默认每隔15s（可以通过–horizontal-pod-autoscaler-sync-period修改）查询metrics的资源使用情况
支持以下三种metrics指标类型：
->预定义metrics（比如Pod的CPU）以利用率的方式计算
->自定义的Pod metrics，以原始值（raw value）的方式计算
->自定义的object metrics
支持两种metrics查询方式：
->Heapster
->自定义的REST API
支持多metrics
准备metrics-server
使用metrics-server作为HPA数据源(metrics-server版本为v0.3.6)
https://github.com/kubernetes-incubator/metrics-server
https://github.com/kubernetes-sigs/metrics-server/tree/v0.3.6
clone 代码
root@master1:/usr/local/src# git clone https://github.com/kubernetes-sigs/metrics-server.git
root@master1:/usr/local/src# ls
metrics-server-0.3.6
root@master1:/usr/local/src# cd metrics-server-0.3.6/
准备image
- google镜像仓库
docker pull k8s.gcr.io/metrics-server-amd64:v0.3.6 - 阿里云镜像仓库
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/metrics-server-amd64:v0.3.6
将metrics-server-amd64:v0.3.6 image 上传到harbor
root@master1:~/package# docker tag mirrorgooglecontainers/metrics-server-amd64:v0.3.6 harbor.linux.com/baseimages/metrics-server-amd64:v0.3.6
root@master1:~/package# docker push harbor.linux.com/baseimages/metrics-server-amd64:v0.3.6
The push refers to repository [harbor.linux.com/baseimages/metrics-server-amd64]
7bf3709d22bb: Pushed
932da5156413: Pushed
v0.3.6: digest: sha256:c9c4e95068b51d6b33a9dccc61875df07dc650abbf4ac1a19d58b4628f89288b size: 738
修改metrics-server yaml文件
root@master1:/usr/local/src/metrics-server-0.3.6/deploy/1.8+# pwd
/usr/local/src/metrics-server-0.3.6/deploy/1.8+
root@master1:/usr/local/src/metrics-server-0.3.6/deploy/1.8+# ls
aggregated-metrics-reader.yaml auth-delegator.yaml auth-reader.yaml metrics-apiservice.yaml metrics-server-deployment.yaml metrics-server-service.yaml resource-reader.yaml
修改image为harbor镜像
root@master1:/usr/local/src/metrics-server-0.3.6/deploy/1.8+# cat metrics-server-deployment.yaml
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: metrics-server
namespace: kube-system
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: metrics-server
namespace: kube-system
labels:
k8s-app: metrics-server
spec:
selector:
matchLabels:
k8s-app: metrics-server
template:
metadata:
name: metrics-server
labels:
k8s-app: metrics-server
spec:
serviceAccountName: metrics-server
volumes:
# mount in tmp so we can safely use from-scratch images and/or read-only containers
- name: tmp-dir
emptyDir: {}
containers:
- name: metrics-server
image: harbor.linux.com/baseimages/metrics-server-amd64:v0.3.6
imagePullPolicy: Always
volumeMounts:
- name: tmp-dir
mountPath: /tmp
创建pod
root@master1:/usr/local/src/metrics-server-0.3.6/deploy/1.8+# kubectl apply -f .
clusterrole.rbac.authorization.k8s.io/system:aggregated-metrics-reader created
clusterrolebinding.rbac.authorization.k8s.io/metrics-server:system:auth-delegator created
rolebinding.rbac.authorization.k8s.io/metrics-server-auth-reader created
apiservice.apiregistration.k8s.io/v1beta1.metrics.k8s.io created
serviceaccount/metrics-server created
deployment.apps/metrics-server created
service/metrics-server created
clusterrole.rbac.authorization.k8s.io/system:metrics-server created
clusterrolebinding.rbac.authorization.k8s.io/system:metrics-server created
验证 metrics-server pod是否运行
root@master1:/usr/local/src/metrics-server-0.3.6/deploy/1.8+# kubectl get pod -A
NAMESPACE NAME READY STATUS RESTARTS AGE
danran danran-nginx-deployment-5f4c68cd88-8ghrp 1/1 Running 0 55m
danran danran-nginx-deployment-5f4c68cd88-ld4gp 1/1 Running 0 19h
danran danran-tomcat-app1-deployment-label-557cd56c58-s295s 1/1 Running 0 20h
default bash-b879cb84b-5k5t8 1/1 Running 0 23h
default busybox 1/1 Running 80 3d8h
default net-test2-565b5f575-b28kf 1/1 Running 2 3d22h
default net-test2-565b5f575-h692c 1/1 Running 2 4d
default net-test2-565b5f575-rlcwz 1/1 Running 1 4d
default net-test2-565b5f575-wwkl2 1/1 Running 1 3d22h
kube-system coredns-85bd4f9784-95qcb 1/1 Running 1 3d7h
kube-system kube-flannel-ds-amd64-4dvn9 1/1 Running 1 4d1h
kube-system kube-flannel-ds-amd64-6zk8z 1/1 Running 1 4d1h
kube-system kube-flannel-ds-amd64-d54j4 1/1 Running 1 4d1h
kube-system kube-flannel-ds-amd64-hmnsj 1/1 Running 1 3d23h
kube-system kube-flannel-ds-amd64-k52kz 1/1 Running 1 4d1h
kube-system kube-flannel-ds-amd64-q42lh 1/1 Running 2 4d1h
kube-system metrics-server-6dc4d646fb-5gf7n 1/1 Running 0 105s
kubernetes-dashboard dashboard-metrics-scraper-665dccf555-xlsm2 1/1 Running 1 3d20h
kubernetes-dashboard kubernetes-dashboard-6d489b6474-h7cqw 1/1 Running 1 3d19h
验证metrics-server pod
验证metrics-server 是否采集到node数据
root@master1:~# kubectl top nodes
NAME CPU(cores) CPU% MEMORY(bytes) MEMORY%
10.203.104.20 44m 1% 2278Mi 31%
10.203.104.21 31m 0% 777Mi 10%
10.203.104.22 45m 1% 706Mi 9%
10.203.104.26 28m 0% 488Mi 6%
10.203.104.27 26m 0% 799Mi 10%
10.203.104.28 29m 0% 538Mi 7%
验证metrics-server 是否采集到pod数据
root@master1:~# kubectl top pods -n danran
NAME CPU(cores) MEMORY(bytes)
danran-nginx-deployment-5f4c68cd88-8ghrp 0m 3Mi
danran-nginx-deployment-5f4c68cd88-ld4gp 0m 4Mi
danran-tomcat-app1-deployment-label-557cd56c58-s295s 1m 265Mi
修改controller-manager启动参数
通过命令配置扩缩容
查看需要配置扩缩容的deployment为danran-tomcat-app1-deployment-label
root@master1:~# kubectl get deployment -n danran
NAME READY UP-TO-DATE AVAILABLE AGE
danran-nginx-deployment 2/2 2 2 20h
danran-tomcat-app1-deployment-label 1/1 1 1 20h
kubectl autoscale 配置自动扩缩容
root@master1:~# kubectl autoscale deployment/danran-tomcat-app1-deployment-label --min=2 --max=10 --cpupercent=80 -n danran
horizontalpodautoscaler.autoscaling/danran-tomcat-app1-podautoscalor created
验证信息
root@master1:~# kubectl describe deployment/danran-tomcat-app1-deployment-label -n danran
desired 最终期望处于READY状态的副本数
updated 当前完成更新的副本数
total 总计副本数
available 当前可用的副本数
unavailable 不可用副本数
yaml文件中定义扩缩容配置
查看需要配置扩缩容的deployment为danran-tomcat-app1-deployment-label
root@master1:~# kubectl get deployment -n danran
NAME READY UP-TO-DATE AVAILABLE AGE
danran-nginx-deployment 2/2 2 2 20h
danran-tomcat-app1-deployment-label 1/1 1 1 20h
在tomcat yaml 同级目录下定义hpa.yaml文件
root@master1:/opt/data/yaml/danran/tomcat-app1# ls
hpa.yaml tomcat-app1.yaml
root@master1:/opt/data/yaml/danran/tomcat-app1# cat hpa.yaml
apiVersion: autoscaling/v1
kind: HorizontalPodAutoscaler
metadata:
namespace: danran
name: danran-tomcat-app1-podautoscalor
labels:
app: danran-tomcat-app1
version: v2beta1
spec:
scaleTargetRef:
apiVersion: apps/v1
kind: Deployment
name: danran-tomcat-app1-deployment-label
minReplicas: 2
maxReplicas: 20
targetCPUUtilizationPercentage: 60
执行HPA pod
root@master1:/opt/data/yaml/danran/tomcat-app1# kubectl apply -f hpa.yaml
horizontalpodautoscaler.autoscaling/danran-tomcat-app1-podautoscalor created
验证HPA
扩容前
root@master1:~# kubectl get deployment -n danran
NAME READY UP-TO-DATE AVAILABLE AGE
danran-nginx-deployment 2/2 2 2 20h
danran-tomcat-app1-deployment-label 1/1 1 1 20h
扩容后
root@master1:~# kubectl get deployment -n danran
NAME READY UP-TO-DATE AVAILABLE AGE
danran-nginx-deployment 2/2 2 2 20h
danran-tomcat-app1-deployment-label 2/2 2 2 20h
查看hpa的状态
root@master1:~# kubectl get hpa -n danran
NAME REFERENCE TARGETS MINPODS MAXPODS REPLICAS AGE
danran-tomcat-app1-podautoscalor Deployment/danran-tomcat-app1-deployment-label 0%/60% 2 20 2 3m31s
root@master1:~# kubectl describe hpa danran-tomcat-app1-podautoscalor -n danran
动态修改资源内容kubectl edit
用于临时修改某些配置后需要立即生效的场景
获取修改调整资源的deployment
root@master1:~# kubectl get deployment -n danran
NAME READY UP-TO-DATE AVAILABLE AGE
danran-nginx-deployment 2/2 2 2 21h
danran-tomcat-app1-deployment-label 4/4 4 4 22h
修改deployment的replicas 副本数
root@master1:~# kubectl edit deployment danran-tomcat-app1-deployment-label -n danran
deployment.apps/danran-tomcat-app1-deployment-label edited
验证副本数是否更新
root@master1:~# kubectl get deployment -n danran
NAME READY UP-TO-DATE AVAILABLE AGE
danran-nginx-deployment 2/2 2 2 21h
danran-tomcat-app1-deployment-label 3/3 3 3 22h
定义node资源标签
lable是一个键值对，创建pod的时候会查询那些node有这个标签，只会将pod创建在符合指定label值的node节点上。
查看当前node label
root@master1:~# kubectl describe node 10.203.104.26
Name: 10.203.104.26
Roles: node
Labels: beta.kubernetes.io/arch=amd64
beta.kubernetes.io/os=linux
kubernetes.io/arch=amd64
kubernetes.io/hostname=10.203.104.26
kubernetes.io/os=linux
kubernetes.io/role=node
Annotations: flannel.alpha.coreos.com/backend-data: {"VtepMAC":"9e:4a:2f:85:86:84"}
flannel.alpha.coreos.com/backend-type: vxlan
flannel.alpha.coreos.com/kube-subnet-manager: true
flannel.alpha.coreos.com/public-ip: 10.203.104.26
node.alpha.kubernetes.io/ttl: 0
volumes.kubernetes.io/controller-managed-attach-detach: true
CreationTimestamp: Sat, 13 Jun 2020 18:57:24 +0800
Taints: <none>
Unschedulable: false
Lease:
HolderIdentity: 10.203.104.26
AcquireTime: <unset>
RenewTime: Wed, 17 Jun 2020 22:15:40 +0800
Conditions:
Type Status LastHeartbeatTime LastTransitionTime Reason Message
---- ------ ----------------- ------------------ ------ -------
MemoryPressure False Wed, 17 Jun 2020 22:15:44 +0800 Sun, 14 Jun 2020 22:35:51 +0800 KubeletHasSufficientMemory kubelet has sufficient memory available
DiskPressure False Wed, 17 Jun 2020 22:15:44 +0800 Sun, 14 Jun 2020 22:35:51 +0800 KubeletHasNoDiskPressure kubelet has no disk pressure
PIDPressure False Wed, 17 Jun 2020 22:15:44 +0800 Sun, 14 Jun 2020 22:35:51 +0800 KubeletHasSufficientPID kubelet has sufficient PID available
Ready True Wed, 17 Jun 2020 22:15:44 +0800 Sun, 14 Jun 2020 22:35:51 +0800 KubeletReady kubelet is posting ready status. AppArmor enabled
Addresses:
InternalIP: 10.203.104.26
Hostname: 10.203.104.26
Capacity:
cpu: 4
ephemeral-storage: 52206Mi
hugepages-1Gi: 0
hugepages-2Mi: 0
memory: 8168080Ki
pods: 110
Allocatable:
cpu: 3800m
ephemeral-storage: 48194020885
hugepages-1Gi: 0
hugepages-2Mi: 0
memory: 7451280Ki
pods: 110
System Info:
Machine ID: 202eb555a5e147b4a4a683e1b0869d19
System UUID: 1BA73542-2622-4635-CDFF-A19A2B87390B
Boot ID: 57bcbc34-a662-477d-a994-1d4986ede5c8
Kernel Version: 4.15.0-106-generic
OS Image: Ubuntu 18.04.4 LTS
Operating System: linux
Architecture: amd64
Container Runtime Version: docker://19.3.8
Kubelet Version: v1.17.4
Kube-Proxy Version: v1.17.4
PodCIDR: 10.20.3.0/24
PodCIDRs: 10.20.3.0/24
Non-terminated Pods: (6 in total)
Namespace Name CPU Requests CPU Limits Memory Requests Memory Limits AGE
--------- ---- ------------ ---------- --------------- ------------- ---
danran danran-nginx-deployment-5f4c68cd88-ld4gp 1 (26%) 2 (52%) 512Mi (7%) 2Gi (28%) 21h
danran danran-tomcat-app1-deployment-label-78c95777df-48j4m 1 (26%) 2 (52%) 512Mi (7%) 2Gi (28%) 11m
default net-test2-565b5f575-b28kf 0 (0%) 0 (0%) 0 (0%) 0 (0%) 4d
default net-test2-565b5f575-h692c 0 (0%) 0 (0%) 0 (0%) 0 (0%) 4d2h
kube-system kube-flannel-ds-amd64-q42lh 100m (2%) 100m (2%) 50Mi (0%) 50Mi (0%) 4d3h
kube-system metrics-server-6dc4d646fb-5gf7n 0 (0%) 0 (0%) 0 (0%) 0 (0%) 122m
Allocated resources:
(Total limits may be over 100 percent, i.e., overcommitted.)
Resource Requests Limits
-------- -------- ------
cpu 2100m (55%) 4100m (107%)
memory 1074Mi (14%) 4146Mi (56%)
ephemeral-storage 0 (0%) 0 (0%)
Events: <none>
自定义node label并验证
添加project=jevon的label
root@master1:~# kubectl label node 10.203.104.27 project=jevon
node/10.203.104.27 labeled
添加project=danran的label
root@master1:~# kubectl label node 10.203.104.26 project=danran
node/10.203.104.26 labeled
验证确认project=danran label
root@master1:~# kubectl describe node 10.203.104.26
Name: 10.203.104.26
Roles: node
Labels: beta.kubernetes.io/arch=amd64
beta.kubernetes.io/os=linux
kubernetes.io/arch=amd64
kubernetes.io/hostname=10.203.104.26
kubernetes.io/os=linux
kubernetes.io/role=node
project=danran
Annotations: flannel.alpha.coreos.com/backend-data: {"VtepMAC":"9e:4a:2f:85:86:84"}
flannel.alpha.coreos.com/backend-type: vxlan
flannel.alpha.coreos.com/kube-subnet-manager: true
flannel.alpha.coreos.com/public-ip: 10.203.104.26
node.alpha.kubernetes.io/ttl: 0
volumes.kubernetes.io/controller-managed-attach-detach: true
yaml引用node label
在Deployment中最后添加nodeSelector.project: danran 字段选择project为danran 的label
root@master1:/opt/data/yaml/danran/tomcat-app1# cat tomcat-app1.yaml
kind: Deployment
apiVersion: apps/v1
metadata:
labels:
app: danran-tomcat-app1-deployment-label
name: danran-tomcat-app1-deployment-label
namespace: danran
spec:
replicas: 1
selector:
matchLabels:
app: danran-tomcat-app1-selector
template:
metadata:
labels:
app: danran-tomcat-app1-selector
spec:
containers:
- name: danran-tomcat-app1-container
image: harbor.linux.com/danran/tomcat-app1:v2
#imagePullPolicy: IfNotPresent
imagePullPolicy: Always
ports:
- containerPort: 8080
protocol: TCP
name: http
env:
- name: "password"
value: "123456"
- name: "age"
value: "18"
resources:
limits:
cpu: 2
memory: 2Gi
requests:
cpu: 1
memory: 512Mi
volumeMounts:
- name: danran-images
mountPath: /usr/local/nginx/html/webapp/images
readOnly: false
- name: danran-static
mountPath: /usr/local/nginx/html/webapp/static
readOnly: false
volumes:
- name: danran-images
nfs:
server: 10.203.104.30
path: /data/danran/images
- name: danran-static
nfs:
server: 10.203.104.30
path: /data/danran/static
nodeSelector:
project: danran
---
kind: Service
apiVersion: v1
metadata:
labels:
app: danran-tomcat-app1-service-label
name: danran-tomcat-app1-service
namespace: danran
spec:
type: NodePort
ports:
- name: http
port: 80
protocol: TCP
targetPort: 8080
nodePort: 40004
selector:
app: danran-tomcat-app1-selector
应用yaml文件
root@master1:/opt/data/yaml/danran/tomcat-app1# kubectl apply -f tomcat-app1.yaml
deployment.apps/danran-tomcat-app1-deployment-label configured
service/danran-tomcat-app1-service unchanged
验证所有tomcat的pod全在label project=danran的Node节点上
root@master1:~# kubectl get pod -A -o wide
删除自定义node label
删除自定义的project label
root@master1:~# kubectl label nodes 10.203.104.26 project-
node/10.203.104.26 labeled
业务镜像版本升级及回滚
在指定的deployment中通过kubectl set image指定新版本的 镜像:tag 来实现更新代码的目的。
构建三个不同版本的nginx镜像，第一次使用v1版本，后组逐渐升级到v2与v3，测试镜像版本升级与回滚操作
升级到镜像到指定版本
v1版本
v1版本，--record=true为记录执行的kubectl
root@master1:/opt/data/yaml/danran/tomcat-app1# kubectl apply -f tomcat-app1.yaml --record=true
deployment.apps/danran-tomcat-app1-deployment-label created
service/danran-tomcat-app1-service created
升级到v5版本
容器的name为danran-tomcat-app1-container，可在tomcat-app1.yaml文件中查看
root@master1:~# kubectl set image deployment/danran-tomcat-app1-deployment-label danran-tomcat-app1-container=harbor.linux.com/danran/tomcat-app1:v5 -n danran
deployment.apps/danran-tomcat-app1-deployment-label image updated
查看历史版本信息
root@master1:~# kubectl rollout history deployment danran-tomcat-app1-deployment-label -n danran
deployment.apps/danran-tomcat-app1-deployment-label
REVISION CHANGE-CAUSE
2 kubectl apply --filename=tomcat-app1.yaml --record=true
3 kubectl apply --filename=tomcat-app1.yaml --record=true
4 kubectl apply --filename=tomcat-app1.yaml --record=true
回滚到上一个版本
将deployment 的danran-tomcat-app1-deployment-label 回滚到上个版本
root@master1:~# kubectl rollout undo deployment danran-tomcat-app1-deployment-label -n danran
deployment.apps/danran-tomcat-app1-deployment-label rolled back
回滚到指定版本
查看需要回滚到的版本
root@master1:~# kubectl rollout history deployment danran-tomcat-app1-deployment-label -n danran
deployment.apps/danran-tomcat-app1-deployment-label
REVISION CHANGE-CAUSE
2 kubectl apply --filename=tomcat-app1.yaml --record=true
3 kubectl apply --filename=tomcat-app1.yaml --record=true
4 kubectl apply --filename=tomcat-app1.yaml --record=true
回滚到REVISION 2
root@master1:~# kubectl rollout undo deployment danran-tomcat-app1-deployment-label --to-revision=2 -n danran
deployment.apps/danran-tomcat-app1-deployment-label rolled back
回滚后的版本
root@master1:~# kubectl rollout history deployment danran-tomcat-app1-deployment-label -n danran
deployment.apps/danran-tomcat-app1-deployment-label
REVISION CHANGE-CAUSE
3 kubectl apply --filename=tomcat-app1.yaml --record=true
4 kubectl apply --filename=tomcat-app1.yaml --record=true
5 kubectl apply --filename=tomcat-app1.yaml --record=true
配置主机为封锁状态且不参与调度
设置10.203.104.27不参与pod调度
root@master1:~# kubectl cordon 10.203.104.27
node/10.203.104.27 cordoned
root@master1:~# kubectl get node
NAME STATUS ROLES AGE VERSION
10.203.104.20 Ready,SchedulingDisabled master 4d5h v1.17.4
10.203.104.21 Ready,SchedulingDisabled master 4d5h v1.17.4
10.203.104.22 Ready,SchedulingDisabled master 4d3h v1.17.4
10.203.104.26 Ready node 4d5h v1.17.4
10.203.104.27 Ready,SchedulingDisabled node 4d5h v1.17.4
10.203.104.28 Ready node 4d5h v1.17.4
设置10.203.104.27参与pod调度
root@master1:~# kubectl uncordon 10.203.104.27
node/10.203.104.27 uncordoned
root@master1:~# kubectl get node
NAME STATUS ROLES AGE VERSION
10.203.104.20 Ready,SchedulingDisabled master 4d5h v1.17.4
10.203.104.21 Ready,SchedulingDisabled master 4d5h v1.17.4
10.203.104.22 Ready,SchedulingDisabled master 4d3h v1.17.4
10.203.104.26 Ready node 4d5h v1.17.4
10.203.104.27 Ready node 4d5h v1.17.4
10.203.104.28 Ready node 4d5h v1.17.4
etcd删除pod
查看和namespace相关的数据
root@etcd1:~# etcdctl get /registry/ --prefix --keys-only | grep danran
从etcd查看具体某个对象的数据
root@etcd1:~# etcdctl get /registry/pods/danran/danran-nginx-deployment-5f4c68cd88-8ghrp
删除etcd指定资源
删除danran-nginx-deployment-5f4c68cd88-8ghrp pod，返回1为删除成功
root@etcd1:~# etcdctl del /registry/pods/danran/danran-nginx-deployment-5f4c68cd88-8ghrp
1标签：kubectl,danran,tomcat,示例,常见,app1,metrics,deployment,K8s 来源： https://www.cnblogs.com/JevonWei/p/13185053.html