kubectl 命令详解
- kubectl 简介
- kubectl 常用操作
- 基本信息查看
- 命名空间的增删改查操作
- 查看 pod 信息
- 项目的生命周期
- 创建
- 发布
- 更新
- 回滚
- 删除
- 金丝雀发布(Canary Release)
- 声明式管理方法
kubectl 简介
kubernetes 集群管理集群资源的唯一入口是通过相应的方法调用 apiserver 的接口。
kubectl 是官方的CLI命令行工具,用于与 apiserver 进行通信,将用户在命令行输入的命令,组织并转化为 apiserver 能识别的信息,进而实现管理 k8s 各种资源的一种有效途径。
k8s中文文档:http://docs.kubernetes.org.cn/683.html
kubectl 常用操作
查看版本信息
kubectl version [--short]
[root@master01 ~]# kubectl version
Client Version: version.Info{Major:"1", Minor:"20", GitVersion:"v1.20.15", GitCommit:"8f1e5bf0b9729a899b8df86249b56e2c74aebc55", GitTreeState:"clean", BuildDate:"2022-01-19T17:27:39Z", GoVersion:"go1.15.15", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"20", GitVersion:"v1.20.15", GitCommit:"8f1e5bf0b9729a899b8df86249b56e2c74aebc55", GitTreeState:"clean", BuildDate:"2022-01-19T17:23:01Z", GoVersion:"go1.15.15", Compiler:"gc", Platform:"linux/amd64"}
[root@master01 ~]# kubectl version --short
Client Version: v1.20.15
Server Version: v1.20.15
查看资源对象简写
kubectl api-resources
[root@master01 ~]# kubectl api-resources
NAME SHORTNAMES APIVERSION NAMESPACED KIND
bindings v1 true Binding
componentstatuses cs v1 false ComponentStatus
... ...
storageclasses sc storage.k8s.io/v1 false StorageClass
volumeattachments storage.k8s.io/v1 false VolumeAttachment
查看集群信息
kubectl cluster-info
kubectl get cs
kubectl get nodes
[root@master01 ~]# kubectl cluster-info
Kubernetes control plane is running at https://192.168.110.10:6443
CoreDNS is running at https://192.168.110.10:6443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy
To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.
[root@master01 ~]# kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME STATUS MESSAGE ERROR
scheduler Healthy ok
controller-manager Healthy ok
etcd-2 Healthy {"health":"true"}
etcd-0 Healthy {"health":"true"}
etcd-1 Healthy {"health":"true"}
[root@master01 ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
192.168.110.20 Ready <none> 21h v1.20.15
192.168.110.30 Ready <none> 19h v1.20.15
配置kubectl自动补全
source <(kubectl completion bash)
node节点查看日志
journalctl -u kubelet -f
基本信息查看
命令格式
kubectl get <resource> [-o wide|json|yaml] [-n namespace]
获取资源的相关信息 -o 指定输出格式 -n 指定命令空间
--all-namespaces 或 -A :表示显示所有命名空间
--show-labels :显示所有标签
-l app :仅显示标签为app的资源
-l app=nginx :仅显示包含app标签,且值为nginx的资源
查看 master 节点状态
componentstatuses 缩写 cs
kubectl get componentstatuses/cs
[root@master01 ~]# kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME STATUS MESSAGE ERROR
controller-manager Healthy ok
scheduler Healthy ok
etcd-1 Healthy {"health":"true"}
etcd-0 Healthy {"health":"true"}
etcd-2 Healthy {"health":"true"}
命名空间的增删改查操作
查看命名空间
命令空间的作用:用于允许不同<命名空间>的<相同类型>的<资源重名>的。
namespace 缩写 ns
kubectl get namespace/cs
[root@master01 ~]# kubectl get ns
NAME STATUS AGE
default Active 21h
kube-flannel Active 19h
kube-node-lease Active 21h
kube-public Active 21h
kube-system Active 21h
kubernetes-dashboard Active 16h
查看某 命名空间 的所有资源(默认是 default)
kubectl get all [-n default]
[root@master01 ~]# kubectl get all -n kube-flannel
NAME READY STATUS RESTARTS AGE
pod/kube-flannel-ds-m86br 1/1 Running 0 19h
pod/kube-flannel-ds-qkjw9 1/1 Running 0 19h
NAME DESIRED CURRENT READY UP-TO-DATE AVAILABLE NODE SELECTOR AGE
daemonset.apps/kube-flannel-ds 2 2 2 2 2 <none> 19h
创建命名空间 sunny
kubectl create ns sunny
[root@master01 ~]# kubectl create ns sunny
namespace/sunny created
[root@master01 ~]# kubectl get ns
NAME STATUS AGE
default Active 22h
kube-flannel Active 19h
kube-node-lease Active 22h
kube-public Active 22h
kube-system Active 22h
kubernetes-dashboard Active 16h
sunny Active 6s
删除命名空间app
kubectl delete namespace sunny
[root@master01 ~]# kubectl delete namespace sunny
namespace "sunny" deleted
副本控制器
在命名空间 sunny 创建副本控制器(deployment)来启动Pod(nginx-sl)
kubectl create deployment nginx-sl --image=nginx -n sunny
[root@master01 ~]# kubectl create deployment nginx-sl --image=nginx -n sunny
deployment.apps/nginx-sl created
查看某 命名空间 下的 pod 信息
kubectl get pod -n sunny
[root@master01 ~]# kubectl get pod -n sunny
NAME READY STATUS RESTARTS AGE
nginx-sl-8c57b4768-t7wxf 1/1 Running 0 112s
描述某个资源的详细信息
kubectl describe deployment nginx-sl -n sunny
kubectl describe pod nginx-sl-8c57b4768-t7wxf -n sunny
[root@master01 ~]# kubectl describe deployment nginx-sl -n sunny
Name: nginx-sl
Namespace: sunny
CreationTimestamp: Tue, 11 Feb 2025 09:35:22 +0800
... ...
NewReplicaSet: nginx-sl-8c57b4768 (1/1 replicas created)
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal ScalingReplicaSet 3m57s deployment-controller Scaled up replica set nginx-sl-8c57b4768 to 1
扩缩容
kubectl scale deployment nginx-sl --replicas=4 -n sunny # 扩容
kubectl scale deployment nginx-sl --replicas=2 -n sunny # 缩容
[root@master01 ~]# kubectl scale deployment nginx-sl --replicas=4 -n sunny
deployment.apps/nginx-sl scaled
[root@master01 ~]# kubectl get pod -n sunny NAME READY STATUS RESTARTS AGE
nginx-sl-8c57b4768-4q9l4 0/1 ContainerCreating 0 15s
nginx-sl-8c57b4768-8vvn6 1/1 Running 0 5m10s
nginx-sl-8c57b4768-fkrwf 1/1 Running 0 15s
nginx-sl-8c57b4768-j8xtv 0/1 ContainerCreating 0 15s
[root@master01 ~]# kubectl scale deployment nginx-sl --replicas=2 -n sunny
deployment.apps/nginx-sl scaled
[root@master01 ~]# kubectl get pod -n sunny
NAME READY STATUS RESTARTS AGE
nginx-sl-8c57b4768-8vvn6 1/1 Running 0 5m32s
nginx-sl-8c57b4768-fkrwf 1/1 Running 0 37s
删除副本控制器
kubectl delete deployment nginx-sl -n sunny
kubectl delete deployment/nginx-sl -n sunny
[root@master01 ~]# kubectl delete deployment/nginx-sl -n sunny
deployment.apps "nginx-sl" deleted
[root@master01 ~]# kubectl get deployment -n sunny
No resources found in sunny namespace.
查看 pod 信息
kubectl exec可以跨主机登录容器,docker exec 只能在容器所在主机上登录
kubectl exec -it nginx-sl-8c57b4768-t7wxf bash -n sunny
[root@master01 ~]# kubectl exec -it nginx-sl-8c57b4768-t7wxf bash -n sunny
kubectl exec [POD] [COMMAND] is DEPRECATED and will be removed in a future version. Use kubectl exec [POD] -- [COMMAND] instead.
root@nginx-sl-8c57b4768-t7wxf:/#
查看Pod中容器的日志
kubectl logs nginx-sl-8c57b4768-t7wxf -n sunny
[root@master01 ~]# kubectl logs nginx-sl-8c57b4768-t7wxf -n sunny
/docker-entrypoint.sh: /docker-entrypoint.d/ is not empty, will attempt to perform configuration
/docker-entrypoint.sh: Looking for shell scripts in /docker-entrypoint.d/
... ...
2025/02/11 01:35:23 [notice] 1#1: start worker process 30
2025/02/11 01:35:23 [notice] 1#1: start worker process 31
删除(重启)pod资源
由于存在deployment/rc之类的副本控制器,删除pod也会重新拉起来
kubectl delete pod nginx-sl-8c57b4768-t7wxf -n sunny
[root@master01 ~]# kubectl delete pod nginx-sl-8c57b4768-t7wxf -n sunny
pod "nginx-sl-8c57b4768-t7wxf" deleted
[root@master01 ~]# kubectl get pod -n sunny
NAME READY STATUS RESTARTS AGE
nginx-sl-8c57b4768-8vvn6 1/1 Running 0 102s
若pod无法删除,总是处于terminate状态,则要强行删除pod
kubectl delete pod <pod-name> -n <namespace> --force --grace-period=0
#grace-period表示过渡存活期,默认30s,在删除pod之前允许pod慢慢终止其上的容器进程,从而优雅退出,0表示立即终止pod
项目的生命周期
项目的生命周期:创建–>发布–>更新–>回滚–>删除
创建
kubectl create命令
创建并运行一个或多个容器镜像。
创建一个deployment 或job 来管理容器。
命令帮助:
kubectl create --help
启动 nginx 实例,暴露容器端口 80,设置副本数 3
kubectl create deployment nginx-sl --image=nginx:1.14 --port=80 --replicas=3 -n sunny
[root@master01 ~]# kubectl create deployment nginx-sl --image=nginx:1.14 --port=80 --replicas=3 -n sunny
deployment.apps/nginx-sl created
[root@master01 ~]# kubectl get deployment -n sunny -o wide
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
nginx-sl 3/3 3 3 2m51s nginx nginx:1.14 app=nginx-sl
[root@master01 ~]# kubectl get pods -n sunny -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-sl-75f8657bd9-g9b2n 1/1 Running 0 3m6s 10.244.60.78 192.168.110.20 <none> <none>
nginx-sl-75f8657bd9-jzw5t 1/1 Running 0 3m6s 10.244.60.77 192.168.110.20 <none> <none>
nginx-sl-75f8657bd9-xzldd 1/1 Running 0 3m6s 10.244.193.68 192.168.110.30 <none> <none>
[root@master01 ~]# kubectl get all
NAME READY STATUS RESTARTS AGE
pod/dns-test 1/1 Running 0 19h
pod/nginx 1/1 Running 0 17h
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.0.0.1 <none> 443/TCP 22h
发布
kubectl expose命令
将资源暴露为新的 Service。
命令帮助:
kubectl expose --help
为deployment的nginx创建service,并通过Service的8080端口转发至容器的80端口上,Service的名称为nginx-service,类型为NodePort
kubectl expose deployment nginx-sl --port=8080 --target-port=80 --name=nginx-service --type=NodePort -n sunny
或者
kubectl create service nodeport nginx-service --tcp=8080:80 -n sunny
[root@master01 ~]# kubectl expose deployment nginx-sl --port=8080 --target-port=80 --name=nginx-service --type=NodePort -n sunny
service/nginx-service exposed
[root@master01 ~]# kubectl delete service --all -n sunny
service "nginx-service" deleted
[root@master01 ~]# kubectl create service nodeport nginx-service --tcp=8080:80 -n sunny
service/nginx-service created
service 的 type 类型:
1、ClusterIP(默认类型):分配一个集群内部的虚拟 IP 地址,仅在集群内部可访问。例如Pod和Pod之间的通信,如果是Kubernetes集群外的请求访问是不行的。
2、NodePort:宿主机上开启一个特定端口(默认范围 30000-32767),直接与Pod的端口相连,实现访问 nodeIP:nodePort 能够直接访问到Pod。用途:允许外部访问,但通常用于开发或测试。
3、LoadBalancer:使用外接负载均衡器完成到服务的负载分发,此模式需要使用云服务商提供的负载均衡器,将请求分发到所有的Node上,再结合kube-proxy实现流量接入:
外部客户端 -> 云负载均衡器 -> Kubernetes 节点 -> kube-proxy -> Pod
4、LoadBalancer和NodePort很相似,目的都是向外部暴露一个端口,区别在于LoadBalancer会在集群的外部再来做一个负载均衡设备,而这个设备需要外部云环境支持的,外部服务发送到这个设备上的请求,会被设备负载均衡转发到K8S集群中。
5、externalName:将外部服务映射到集群内部,并以DNS的形式用于Pod中服务对外部服务访问。
查看pod网络状态详细信息和 Service暴露的端口
kubectl get pods,svc -o wide -n sunny
[root@master01 ~]# kubectl get pods,svc -o wide -n sunny
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod/nginx-sl-75f8657bd9-g9b2n 1/1 Running 0 53m 10.244.60.78 192.168.110.20 <none> <none>
pod/nginx-sl-75f8657bd9-jzw5t 1/1 Running 0 53m 10.244.60.77 192.168.110.20 <none> <none>
pod/nginx-sl-75f8657bd9-xzldd 1/1 Running 0 53m 10.244.193.68 192.168.110.30 <none> <none>
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
service/nginx-service NodePort 10.0.0.27 <none> 8080:38329/TCP 11m app=nginx-sl
查看关联后端的节点
kubectl get endpoints -n sunny
[root@master01 ~]# kubectl get endpoints -n sunny
NAME ENDPOINTS AGE
nginx-service 10.244.193.68:80,10.244.60.77:80,10.244.60.78:80 10m
查看 service 的描述信息
kubectl describe svc nginx -n sunny
[root@master01 ~]# kubectl describe svc nginx -n sunny
Name: nginx-service
Namespace: sunny
Labels: app=nginx-sl
Annotations: <none>
Selector: app=nginx-sl
Type: NodePort
IP Families: <none>
IP: 10.0.0.27
IPs: 10.0.0.27
Port: <unset> 8080/TCP
TargetPort: 80/TCP
NodePort: <unset> 38329/TCP
Endpoints: 10.244.193.68:80,10.244.60.77:80,10.244.60.78:80
Session Affinity: None
External Traffic Policy: Cluster
Events: <none>
在 node01 节点上操作,查看负载均衡端口
yum install ipvsadm -y
ipvsadm -Ln
#外部访问的IP和端口
TCP 192.168.110.20:38329 rr
-> 10.244.60.77:80 Masq 1 0 0
-> 10.244.60.78:80 Masq 1 0 0
-> 10.244.193.68:80 Masq 1 0 0
#pod集群组内部访问的IP和端口
TCP 10.0.0.27:8080 rr
-> 10.244.60.77:80 Masq 1 0 0
-> 10.244.60.78:80 Masq 1 0 0
-> 10.244.193.68:80 Masq 1 0 0
在 node02 节点上操作,同样方式查看负载均衡端口
访问
curl 10.0.0.27
curl 192.168.110.20:38329
在master01操作 查看访问日志
kubectl logs [容器名]
更新
kubectl set
更新:更改现有应用资源一些信息。
命令帮助:
kubectl set --help
查看当前 nginx 的版本号
curl -I http://192.168.110.20:38329
curl -I http://192.168.110.30:38329
[root@master01 ~]# curl -I http://192.168.110.20:38329
HTTP/1.1 200 OK
Server: nginx/1.14.2
Date: Tue, 11 Feb 2025 03:25:58 GMT
Content-Type: text/html
Content-Length: 612
Last-Modified: Tue, 04 Dec 2018 14:44:49 GMT
Connection: keep-alive
ETag: "5c0692e1-264"
Accept-Ranges: bytes
将nginx 版本更新为 1.15 版本
kubectl set image deployment/nginx nginx=nginx:1.15
[root@master01 ~]# kubectl set image deployment/nginx-sl nginx=nginx:1.15 -n sunny
deployment.apps/nginx-sl image updated
[root@master01 ~]# curl -I http://192.168.110.20:38329
HTTP/1.1 200 OK
Server: nginx/1.15.12
Date: Tue, 11 Feb 2025 03:27:51 GMT
Content-Type: text/html
Content-Length: 612
Last-Modified: Tue, 16 Apr 2019 13:08:19 GMT
Connection: keep-alive
ETag: "5cb5d3c3-264"
Accept-Ranges: bytes
#更新需要时间
处于动态监听 pod 状态,由于使用的是滚动更新方式,所以会先生成一个新的pod,然后删除一个旧的pod,往后依次类推
kubectl get pods -w
滚动更新通过参数 maxSurge 和 maxUnavailable 来控制副本替换的数量
maxSurge:此参数控制滚动更新过程中副本总数的超过 DESIRED 的上限。maxSurge 可以是具体的整数(比如 3),也可以是百分百,向上取整。maxSurge 默认值为 25%。
例如,DESIRED 为 10,那么副本总数的最大值为 10 + 10 * 25% = 13,即 CURRENT 为 13。
maxUnavailable:此参数控制滚动更新过程中,不可用的副本相占 DESIRED 的最大比例。maxUnavailable 可以是具体的整数(比如 3),也可以是百分百,向下取整。 maxUnavailable 默认值为 25%。
例如,DESIRED 为 10,那么可用的副本数至少要为 10 - 10 * 25% = 8,即 AVAILABLE 为 8。
因此 maxSurge 值越大,初始创建的新副本数量就越多;maxUnavailable 值越大,初始销毁的旧副本数量就越多。
理想情况下,DESIRED 为 10 的滚动更新的过程应该是这样的:
首先创建 3 个新副本使副本总数达到 13 个。
然后销毁 2 个旧副本使可用的副本数降到 8 个。
当这 2 个旧副本成功销毁后,可再创建 2 个新副本,使副本总数保持为 13 个。
当新副本通过 Readiness 探测后,会使可用副本数增加,超过 8。
进而可以继续销毁更多的旧副本,使可用副本数回到 8。
旧副本的销毁使副本总数低于 13,这样就允许创建更多的新副本。
这个过程会持续进行,最终所有的旧副本都会被新副本替换,滚动更新完成。
更新好后的 Pod 的 ip 会改变
kubectl get pods -o wide
[root@master01 ~]# kubectl get pods -o wide -n sunny
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-sl-7554b9bbfd-5ffbb 1/1 Running 0 25m 10.244.60.81 192.168.110.20 <none> <none>
nginx-sl-7554b9bbfd-kzzjz 1/1 Running 0 26m 10.244.60.80 192.168.110.20 <none> <none>
nginx-sl-7554b9bbfd-zlhzp 1/1 Running 0 26m 10.244.193.69 192.168.110.30 <none> <none>
回滚
kubectl rollout
命令帮助:
kubectl rollout --help
查看历史版本
kubectl rollout history deployment/nginx-sl -n sunny
[root@master01 ~]# kubectl rollout history deployment/nginx-sl -n sunny
deployment.apps/nginx-sl
REVISION CHANGE-CAUSE
1 <none>
2 <none>
执行回滚到上一个版本
kubectl rollout undo deployment/nginx-sl -n sunny
[root@master01 ~]# kubectl rollout undo deployment/nginx-sl -n sunny
deployment.apps/nginx-sl rolled back
[root@master01 ~]# curl -I http://192.168.110.20:38329
HTTP/1.1 200 OK
Server: nginx/1.14.2
Date: Tue, 11 Feb 2025 03:56:57 GMT
Content-Type: text/html
Content-Length: 612
Last-Modified: Tue, 04 Dec 2018 14:44:49 GMT
Connection: keep-alive
ETag: "5c0692e1-264"
Accept-Ranges: bytes
执行回滚到指定版本
kubectl rollout undo deployment/nginx-sl --to-revision=2 -n sunny
[root@master01 ~]# kubectl rollout history deployment/nginx-sl -n sunny
deployment.apps/nginx-sl
REVISION CHANGE-CAUSE
2 <none>
3 <none>
[root@master01 ~]# kubectl rollout undo deployment/nginx-sl --to-revision=2 -n sunny
deployment.apps/nginx-sl rolled back
检查回滚状态
kubectl rollout status deployment/nginx-sl -n sunny
[root@master01 ~]# kubectl rollout status deployment/nginx-sl -n sunny
deployment "nginx-sl" successfully rolled out
[root@master01 ~]# curl -I http://192.168.110.20:38329
HTTP/1.1 200 OK
Server: nginx/1.15.12
Date: Tue, 11 Feb 2025 03:59:43 GMT
Content-Type: text/html
Content-Length: 612
Last-Modified: Tue, 16 Apr 2019 13:08:19 GMT
Connection: keep-alive
ETag: "5cb5d3c3-264"
Accept-Ranges: bytes
删除
kubectl delete
删除副本控制器
kubectl delete deployment/nginx-sl -n sunny
[root@master01 ~]# kubectl delete deployment/nginx-sl -n sunny
deployment.apps "nginx-sl" deleted
删除service
kubectl delete svc/nginx-service -n sunny
[root@master01 ~]# kubectl delete svc/nginx-service -n sunny
service "nginx-service" deleted
[root@master01 ~]# kubectl get all -n sunny
No resources found in sunny namespace.
金丝雀发布(Canary Release)
Deployment控制器支持自定义控制更新过程中的滚动节奏,如“暂停(pause)”或“继续(resume)”更新操作。比如等待第一批新的Pod资源创建完成后立即暂停更新过程,此时,仅存在一部分新版本的应用,主体部分还是旧的版本。然后,再筛选一小部分的用户请求路由到新版本的Pod应用,继续观察能否稳定地按期望的方式运行。确定没问题之后再继续完成余下的Pod资源滚动更新,否则立即回滚更新操作。这就是所谓的金丝雀发布。
模拟金丝雀发布
环境
[root@master01 ~]# kubectl get pod
NAME READY STATUS RESTARTS AGE
nginx 1/1 Running 0 19h
nginx-d9d8cf5c7-4mjm8 1/1 Running 0 2m48s
nginx-d9d8cf5c7-jvt2v 1/1 Running 0 12s
nginx-d9d8cf5c7-kzbpv 1/1 Running 0 2m48s
nginx-d9d8cf5c7-mpwbv 1/1 Running 0 2m48s
nginx-d9d8cf5c7-nm4ph 1/1 Running 0 12s
更新deployment的版本,并配置暂停deployment
kubectl set image deployment/nginx nginx=nginx:1.17 && kubectl rollout pause deployment/nginx
[root@master01 ~]# kubectl set image deployment/nginx nginx=nginx:1.17 && kubectl rollout pause deployment/nginx
deployment.apps/nginx image updated
deployment.apps/nginx paused
监控更新的过程,可以看到已经新增了一个资源,但是并未按照预期的状态去删除一个旧的资源,就是因为使用了pause暂停命令
kubectl get pods -w
[root@master01 ~]# kubectl rollout status deployment/nginx
Waiting for deployment "nginx" rollout to finish: 3 out of 5 new replicas have been updated...
Waiting for deployment "nginx" rollout to finish: 3 out of 5 new replicas have been updated...
Waiting for deployment "nginx" rollout to finish: 3 out of 5 new replicas have been updated...
... ...
确保更新的pod没问题了,继续更新
kubectl rollout resume deployment/nginx
[root@master01 ~]# kubectl rollout resume deployment/nginx
deployment.apps/nginx resumed
查看最后的更新情况
kubectl get pods -w
[root@master01 ~]# kubectl get pods -w
NAME READY STATUS RESTARTS AGE
nginx 1/1 Running 0 20h
nginx-7f4fc68488-7lfl8 1/1 Running 0 7s
nginx-7f4fc68488-dfk92 1/1 Running 0 7s
nginx-7f4fc68488-dq6n6 1/1 Running 0 9m23s
nginx-7f4fc68488-qzj4q 1/1 Running 0 9m23s
nginx-7f4fc68488-xxmh2 1/1 Running 0 9m23s
nginx-d9d8cf5c7-jvt2v 0/1 Terminating 0 10m
nginx-d9d8cf5c7-kzbpv 0/1 Terminating 0 12m
nginx-d9d8cf5c7-kzbpv 0/1 Terminating 0 12m
nginx-d9d8cf5c7-kzbpv 0/1 Terminating 0 12m
nginx-d9d8cf5c7-jvt2v 0/1 Terminating 0 10m
nginx-d9d8cf5c7-jvt2v 0/1 Terminating 0 10m
声明式管理方法
适用场景:对资源的修改操作
管理方式:依赖于资源配置清单文件对资源进行管理
资源配置清单文件有两种格式:yaml(人性化,易读),json(易于api接口解析)
对资源的管理,是通过事先定义在统一资源配置清单内,再通过陈述式命令应用到k8s集群里
语法格式:kubectl create/apply/delete -f xxxx.yaml
查看资源配置清单
kubectl get deployment nginx -o yaml
[root@master01 ~]# kubectl get deployment nginx -o yaml
apiVersion: apps/v1
kind: Deployment
metadata:
annotations:
deployment.kubernetes.io/revision: "2"
creationTimestamp: "2025-02-11T04:41:06Z"
generation: 5
labels:
app: nginx
managedFields:
- apiVersion: apps/v1
fieldsType: FieldsV1
... ...
readyReplicas: 5
replicas: 5
updatedReplicas: 5
解释资源配置清单
kubectl explain deployment.metadata
kubectl explain deployment.metadata
KIND: Deployment
VERSION: apps/v1
... ...
allowed to change on PUT operations.
Populated by the system. Read-only. More info:
http://kubernetes.io/docs/user-guide/identifiers#uids
修改资源配置清单并应用
离线修改:
修改yaml文件,并用 kubectl apply -f xxxx.yaml 文件使之生效
注意:当apply不生效时,先使用delete清除资源,再apply创建资源
#导出配置文件
kubectl get service nginx -o yaml > nginx-svc.yaml
#修改
vim nginx-svc.yaml
#删除
kubectl delete -f nginx-svc.yaml
#加载
kubectl apply -f nginx-svc.yaml
#查看
kubectl get svc
在线修改:
直接使用 kubectl edit service nginx 在线编辑资源配置清单并保存退出即时生效(如port: 888)
此修改方式不会对yaml文件内容修改
删除资源配置清单
陈述式删除:
kubectl delete service nginx
声明式删除:
kubectl delete -f nginx-svc.yaml