[root@master ~ 13:41:19]# kubectl -h
kubectl controls the Kubernetes cluster manager.
Find more information at: https://kubernetes.io/docs/reference/kubectl/
Basic Commands (Beginner):
create Create a resource from a file or from stdin
expose Take a replication controller, service, deployment or pod and expose it as a new
Kubernetes service
run 在集群上运行特定镜像
set 为对象设置指定特性
Basic Commands (Intermediate):
explain Get documentation for a resource
get 显示一个或多个资源
edit 编辑服务器上的资源
delete Delete resources by file names, stdin, resources and names, or by resources and
label selector
Deploy Commands:
rollout Manage the rollout of a resource
scale Set a new size for a deployment, replica set, or replication controller
autoscale Auto-scale a deployment, replica set, stateful set, or replication controller
Cluster Management Commands:
certificate Modify certificate resources
cluster-info Display cluster information
top Display resource (CPU/memory) usage
cordon 标记节点为不可调度
uncordon 标记节点为可调度
drain 清空节点以准备维护
taint 更新一个或者多个节点上的污点
Troubleshooting and Debugging Commands:
describe 显示特定资源或资源组的详细信息
logs 打印 Pod 中容器的日志
attach 挂接到一个运行中的容器
exec 在某个容器中执行一个命令
port-forward 将一个或多个本地端口转发到某个 Pod
proxy 运行一个指向 Kubernetes API 服务器的代理
cp Copy files and directories to and from containers
auth Inspect authorization
debug Create debugging sessions for troubleshooting workloads and nodes
events List events
Advanced Commands:
diff Diff the live version against a would-be applied version
apply Apply a configuration to a resource by file name or stdin
patch Update fields of a resource
replace Replace a resource by file name or stdin
wait Experimental: Wait for a specific condition on one or many resources
kustomize Build a kustomization target from a directory or URL
Settings Commands:
label 更新某资源上的标签
annotate 更新一个资源的注解
completion Output shell completion code for the specified shell (bash, zsh, fish, or
powershell)
Other Commands:
api-resources Print the supported API resources on the server
api-versions Print the supported API versions on the server, in the form of "group/version"
config 修改 kubeconfig 文件
plugin Provides utilities for interacting with plugins
version 输出客户端和服务端的版本信息
Usage:
kubectl [flags] [options]
Use "kubectl <command> --help" for more information about a given command.
Use "kubectl options" for a list of global command-line options (applies to all commands).
[root@master ~ 17:29:03]# kubectl explain deployment
GROUP: apps
KIND: Deployment
VERSION: v1
DESCRIPTION:
Deployment enables declarative updates for Pods and ReplicaSets.
FIELDS:
apiVersion <string>
APIVersion defines the versioned schema of this representation of an object.
Servers should convert recognized schemas to the latest internal value, and
may reject unrecognized values. More info:
https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#resources
kind <string>
Kind is a string value representing the REST resource this object
represents. Servers may infer this from the endpoint the client submits
requests to. Cannot be updated. In CamelCase. More info:
https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds
metadata <ObjectMeta>
Standard object's metadata. More info:
https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
spec <DeploymentSpec>
Specification of the desired behavior of the Deployment.
status <DeploymentStatus>
Most recently observed status of the Deployment.
# 还可以继续深入
[root@master ~ 17:29:40]# kubectl explain deployment.spec
GROUP: apps
KIND: Deployment
VERSION: v1
FIELD: spec <DeploymentSpec>
DESCRIPTION:
Specification of the desired behavior of the Deployment.
DeploymentSpec is the specification of the desired behavior of the
Deployment.
FIELDS:
minReadySeconds <integer>
Minimum number of seconds for which a newly created pod should be ready
without any of its container crashing, for it to be considered available.
Defaults to 0 (pod will be considered available as soon as it is ready)
paused <boolean>
Indicates that the deployment is paused.
progressDeadlineSeconds <integer>
The maximum time in seconds for a deployment to make progress before it is
considered to be failed. The deployment controller will continue to process
failed deployments and a condition with a ProgressDeadlineExceeded reason
will be surfaced in the deployment status. Note that progress will not be
estimated during the time a deployment is paused. Defaults to 600s.
replicas <integer>
Number of desired pods. This is a pointer to distinguish between explicit
zero and not specified. Defaults to 1.
revisionHistoryLimit <integer>
The number of old ReplicaSets to retain to allow rollback. This is a pointer
to distinguish between explicit zero and not specified. Defaults to 10.
selector <LabelSelector> -required-
Label selector for pods. Existing ReplicaSets whose pods are selected by
this will be the ones affected by this deployment. It must match the pod
template's labels.
strategy <DeploymentStrategy>
The deployment strategy to use to replace existing pods with new ones.
template <PodTemplateSpec> -required-
Template describes the pods that will be created. The only allowed
template.spec.restartPolicy value is "Always".
# 可以把不再使用的pod删除
kubectl delete pod pod_name -n ns_name
# 强制删除
kubectl delete pod pod_name -n ns_name --grace-period=0 --force
查看资源创建过程
bash复制代码
[root@master ~ 17:13:27]# kubectl describe pod metrics-server-57999c5cf7-56szn -n kube-system
现在可以使用kubectl top 查看资源了
bash复制代码
# pod
[root@master ~ 18:42:32]# kubectl top pod -n kube-system
NAME CPU(cores) MEMORY(bytes)
calico-kube-controllers-658d97c59c-dnj7l 2m 72Mi
calico-node-b2nrt 17m 96Mi
calico-node-d74vl 14m 86Mi
calico-node-z8w5n 18m 128Mi
coredns-66f779496c-nzpjw 1m 18Mi
coredns-66f779496c-wzrkp 1m 66Mi
etcd-master 12m 154Mi
kube-apiserver-master 28m 279Mi
kube-controller-manager-master 7m 153Mi
kube-proxy-qjz9p 4m 81Mi
kube-proxy-stz98 3m 81Mi
kube-proxy-tzsgh 4m 82Mi
kube-scheduler-master 3m 74Mi
metrics-server-57999c5cf7-56szn 2m 21Mi
# 指定pod
[root@master ~ 17:17:12]# kubectl top pod kube-apiserver-master -n kube-system
NAME CPU(cores) MEMORY(bytes)
kube-apiserver-master 28m 282Mi
# node
[root@master ~ 17:18:29]# kubectl top node node1
NAME CPU(cores) CPU% MEMORY(bytes) MEMORY%
node1 61m 1% 1295Mi 33%
[root@master ~ 17:19:36]# kubectl top node node2
NAME CPU(cores) CPU% MEMORY(bytes) MEMORY%
node2 59m 1% 1398Mi 36%
显示集群信息
bash复制代码
[root@master ~ 18:42:13]# kubectl cluster-info
Kubernetes control plane is running at https://192.168.108.128:6443
CoreDNS is running at https://192.168.108.128:6443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy
To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.
[root@master ~ 18:55:56]# kubectl version
Client Version: v1.28.0
Kustomize Version: v5.0.4-0.20230601165947-6ce0bf390ce3
Server Version: v1.28.0
集群Node管理
查看集群信息
bash复制代码
[root@master ~ 18:56:02]# kubectl cluster-info
Kubernetes control plane is running at https://192.168.108.128:6443
CoreDNS is running at https://192.168.108.128:6443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy
To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.
查看节点信息
bash复制代码
# 查看集群节点信息
[root@master ~ 18:57:14]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master Ready control-plane 29h v1.28.0
node1 Ready <none> 29h v1.28.0
node2 Ready <none> 29h v1.28.0
# 查看集群节点详细信息
[root@master ~ 18:57:44]# kubectl get nodes -o wide
NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME
master Ready control-plane 29h v1.28.0 192.168.108.128 <none> CentOS Linux 7 (Core) 3.10.0-1160.119.1.el7.x86_64 docker://26.1.4
node1 Ready <none> 29h v1.28.0 192.168.108.129 <none> CentOS Linux 7 (Core) 3.10.0-1160.119.1.el7.x86_64 docker://26.1.4
node2 Ready <none> 29h v1.28.0 192.168.108.136 <none> CentOS Linux 7 (Core) 3.10.0-1160.119.1.el7.x86_64 docker://26.1.4
# 查看节点描述详细信息
[root@master ~ 18:58:15]# kubectl describe node master
Name: master
Roles: control-plane
Labels: beta.kubernetes.io/arch=amd64
beta.kubernetes.io/os=linux
kubernetes.io/arch=amd64
kubernetes.io/hostname=master
kubernetes.io/os=linux
node-role.kubernetes.io/control-plane=
node.kubernetes.io/exclude-from-external-load-balancers=
Annotations: kubeadm.alpha.kubernetes.io/cri-socket: unix:///var/run/cri-dockerd.sock
node.alpha.kubernetes.io/ttl: 0
projectcalico.org/IPv4Address: 192.168.108.128/24
projectcalico.org/IPv4IPIPTunnelAddr: 10.244.219.64
volumes.kubernetes.io/controller-managed-attach-detach: true
CreationTimestamp: Wed, 14 Jan 2026 13:18:45 +0800
Taints: node-role.kubernetes.io/control-plane:NoSchedule
Unschedulable: false
Lease:
HolderIdentity: master
AcquireTime: <unset>
RenewTime: Thu, 15 Jan 2026 19:00:28 +0800
Conditions:
Type Status LastHeartbeatTime LastTransitionTime Reason Message
---- ------ ----------------- ------------------ ------ -------
NetworkUnavailable False Thu, 15 Jan 2026 17:24:43 +0800 Thu, 15 Jan 2026 17:24:43 +0800 CalicoIsUp Calico is running on this node
MemoryPressure False Thu, 15 Jan 2026 18:58:04 +0800 Wed, 14 Jan 2026 13:18:43 +0800 KubeletHasSufficientMemory kubelet has sufficient memory available
DiskPressure False Thu, 15 Jan 2026 18:58:04 +0800 Wed, 14 Jan 2026 13:18:43 +0800 KubeletHasNoDiskPressure kubelet has no disk pressure
PIDPressure False Thu, 15 Jan 2026 18:58:04 +0800 Wed, 14 Jan 2026 13:18:43 +0800 KubeletHasSufficientPID kubelet has sufficient PID available
Ready True Thu, 15 Jan 2026 18:58:04 +0800 Wed, 14 Jan 2026 13:36:01 +0800 KubeletReady kubelet is posting ready status
Addresses:
InternalIP: 192.168.108.128
Hostname: master
Capacity:
cpu: 2
ephemeral-storage: 51175Mi
hugepages-1Gi: 0
hugepages-2Mi: 0
memory: 4025936Ki
pods: 110
Allocatable:
cpu: 2
ephemeral-storage: 48294789041
hugepages-1Gi: 0
hugepages-2Mi: 0
memory: 3923536Ki
pods: 110
System Info:
Machine ID: a2577c64b416419ab2e1e8bc9dd8a71d
System UUID: 3D344D56-B458-78AB-81FF-4DAD0293F9D6
Boot ID: 770c6db9-3cf2-429e-b878-2ad476a86431
Kernel Version: 3.10.0-1160.119.1.el7.x86_64
OS Image: CentOS Linux 7 (Core)
Operating System: linux
Architecture: amd64
Container Runtime Version: docker://26.1.4
Kubelet Version: v1.28.0
Kube-Proxy Version: v1.28.0
PodCIDR: 10.244.0.0/24
PodCIDRs: 10.244.0.0/24
Non-terminated Pods: (9 in total)
Namespace Name CPU Requests CPU Limits Memory Requests Memory Limits Age
--------- ---- ------------ ---------- --------------- ------------- ---
kube-system calico-kube-controllers-658d97c59c-dnj7l 0 (0%) 0 (0%) 0 (0%) 0 (0%) 29h
kube-system calico-node-d74vl 250m (12%) 0 (0%) 0 (0%) 0 (0%) 95m
kube-system coredns-66f779496c-nzpjw 100m (5%) 0 (0%) 70Mi (1%) 170Mi (4%) 29h
kube-system coredns-66f779496c-wzrkp 100m (5%) 0 (0%) 70Mi (1%) 170Mi (4%) 29h
kube-system etcd-master 100m (5%) 0 (0%) 100Mi (2%) 0 (0%) 29h
kube-system kube-apiserver-master 250m (12%) 0 (0%) 0 (0%) 0 (0%) 29h
kube-system kube-controller-manager-master 200m (10%) 0 (0%) 0 (0%) 0 (0%) 29h
kube-system kube-proxy-stz98 0 (0%) 0 (0%) 0 (0%) 0 (0%) 29h
kube-system kube-scheduler-master 100m (5%) 0 (0%) 0 (0%) 0 (0%) 29h
Allocated resources:
(Total limits may be over 100 percent, i.e., overcommitted.)
Resource Requests Limits
-------- -------- ------
cpu 1100m (55%) 0 (0%)
memory 240Mi (6%) 340Mi (8%)
ephemeral-storage 0 (0%) 0 (0%)
hugepages-1Gi 0 (0%) 0 (0%)
hugepages-2Mi 0 (0%) 0 (0%)
Events: <none>
Worker Node节点管理集群
在工作节点使用kubeadm安装，在node节点管理就会报错
bash复制代码
[root@node1 ~ 19:02:18]# kubectl get nodes
E0115 19:02:31.739224 80489 memcache.go:265] couldn't get current server API group list: Get "http://localhost:8080/api?timeout=32s": dial tcp [::1]:8080: connect: connection refused
E0115 19:02:31.740080 80489 memcache.go:265] couldn't get current server API group list: Get "http://localhost:8080/api?timeout=32s": dial tcp [::1]:8080: connect: connection refused
E0115 19:02:31.741875 80489 memcache.go:265] couldn't get current server API group list: Get "http://localhost:8080/api?timeout=32s": dial tcp [::1]:8080: connect: connection refused
E0115 19:02:31.743474 80489 memcache.go:265] couldn't get current server API group list: Get "http://localhost:8080/api?timeout=32s": dial tcp [::1]:8080: connect: connection refused
E0115 19:02:31.745347 80489 memcache.go:265] couldn't get current server API group list: Get "http://localhost:8080/api?timeout=32s": dial tcp [::1]:8080: connect: connection refused
The connection to the server localhost:8080 was refused - did you specify the right host or port?
[root@master ~ 19:40:18]# kubectl get nodes --show-labels
NAME STATUS ROLES AGE VERSION LABELS
master Ready control-plane 30h v1.28.0 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=master,kubernetes.io/os=linux,node-role.kubernetes.io/control-plane=,node.kubernetes.io/exclude-from-external-load-balancers=
node1 Ready <none> 30h v1.28.0 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=node1,kubernetes.io/os=linux
node2 Ready <none> 30h v1.28.0 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=node2,kubernetes.io/os=linux
设置节点标签信息
为节点node2打上一个region=nanjing的标签
bash复制代码
[root@master ~ 19:42:32]# kubectl label node node2 region=nanjing
node/node2 labeled
# 查看标签
[root@master ~ 19:45:15]# kubectl get nodes --show-labels
NAME STATUS ROLES AGE VERSION LABELS
... ...
node2 Ready <none> 30h v1.28.0 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=node2,kubernetes.io/os=linux,region=nanjing
查看所有节点带region的标签
bash复制代码
[root@master ~ 19:47:10]# kubectl get nodes -L region
NAME STATUS ROLES AGE VERSION REGION
master Ready control-plane 30h v1.28.0
node1 Ready <none> 30h v1.28.0
node2 Ready <none> 30h v1.28.0 nanjing
多维度标签
设置多维度标签，用于不同的需要区分的场景
比如把node1标签为合肥，南区机房，测试环境，AI业务
bash复制代码
[root@master ~ 19:47:18]# kubectl get nodes node1 --show-labels NAME STATUS ROLES AGE VERSION LABELS
node1 Ready <none> 30h v1.28.0 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=node1,kubernetes.io/os=linux
[root@master ~ 19:48:20]# kubectl label node node1 region=hefei zone=south env=test bussiness=AI
node/node1 labeled
[root@master ~ 19:49:46]# kubectl get nodes node1 --show-labels NAME STATUS ROLES AGE VERSION LABELS
node1 Ready <none> 30h v1.28.0 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,bussiness=AI,env=test,kubernetes.io/arch=amd64,kubernetes.io/hostname=node1,kubernetes.io/os=linux,region=hefei,zone=south
显示节点的相应标签
-L大写L只需要写键名即可
bash复制代码
[root@master ~ 19:50:07]# kubectl get nodes -L region,zone,env
NAME STATUS ROLES AGE VERSION REGION ZONE ENV
master Ready control-plane 30h v1.28.0
node1 Ready <none> 30h v1.28.0 hefei south test
node2 Ready <none> 30h v1.28.0 nanjing
键值匹配标签-l小写的L（键值对用小写l；键名用大写L）
需要键值写全
bash复制代码
[root@master ~ 19:52:19]# kubectl get nodes -l region=hefei
NAME STATUS ROLES AGE VERSION
node1 Ready <none> 30h v1.28.0
标签修改（overwrite:使用复写功能）
bash复制代码
[root@master test_dir 15:59:13]# kubectl label nodes node1 zone=west --overwrite
node/node1 labeled
[root@master test_dir 16:02:41]# kubectl get nodes node1 -L zone
NAME STATUS ROLES AGE VERSION ZONE
node1 Ready <none> 2d2h v1.28.0 west
标签删除
使用key后面加-减号的写法来取消标签
bash复制代码
[root@master test_dir 16:03:26]# kubectl get node node1 --show-labels
NAME STATUS ROLES AGE VERSION LABELS
node1 Ready <none> 2d2h v1.28.0 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,bussiness=AI,env=test,kubernetes.io/arch=amd64,kubernetes.io/hostname=node1,kubernetes.io/os=linux,region=hefei,zone=west
# 批量删除标签
[root@master test_dir 16:04:59]# kubectl label node node1 env- bussiness- region- zone-
node/node1 unlabeled
# 查看标签
[root@master test_dir 16:06:04]# kubectl get node node1 --show-labels
NAME STATUS ROLES AGE VERSION LABELS
node1 Ready <none> 2d2h v1.28.0 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=node1,kubernetes.io/os=linux
标签选择
用于筛选匹配到特定标签的资源，主要分两类：
等值匹配（Equality-based）
精确匹配键值：app=nginx（匹配 app 值为 nginx 的资源）
排除匹配：env!=dev（排除 env=dev 的资源）
集合匹配（Set-based）
"key in (value1, value2)"：匹配值在集合中的资源
"key notin (value1)"：拆除指定值
存在性检查：key（仅检查键时候存在）
bash复制代码
[root@master test_dir 16:06:07]# kubectl label node node1 env=test1
node/node1 labeled
[root@master test_dir 17:07:06]# kubectl label node node2 env=test2
node/node2 labeled
[root@master test_dir 17:07:20]# kubectl get nodes -l env!=test1
NAME STATUS ROLES AGE VERSION
master Ready control-plane 2d3h v1.28.0
node2 Ready <none> 2d3h v1.28.0
[root@master test_dir 17:07:46]# kubectl get nodes -l "env in(test1,test2)"
NAME STATUS ROLES AGE VERSION
node1 Ready <none> 2d3h v1.28.0
node2 Ready <none> 2d3h v1.28.0
[root@master test_dir 18:00:53]# kubectl apply -f namespace.yaml
namespace/web-test created
[root@master test_dir 18:01:02]# kubectl get ns
NAME STATUS AGE
default Active 2d4h
kube-node-lease Active 2d4h
kube-public Active 2d4h
kube-system Active 2d4h
kubernetes-dashboard Active 2d2h
web-test Active 22s
[root@master test_dir 18:15:05]# kubectl apply -f tomcat.yaml
configmap/tomcat-web-content created
deployment.apps/tomcat-test created
service/tomcat-service created
[root@master ~ 09:14:14]# kubectl get namespaces
# namespaces可以简写成namespace或ns
NAME STATUS AGE
default Active 4d20h # 所有未指定Namespace的对象都会被默认分配在default命名空间
kube-node-lease Active 4d20h
kube-public Active 4d20h # 此命名空间下的资源可以被所有人访问
kube-system Active 4d20h # 所有由Kubernetes系统创建的资源都处于这个命名空间
kubernetes-dashboard Active 4d18h
web-test Active 2d15h
查看namespace中的资源
命令kubectl get all --namespace=命名空间名称 可以查看此命名空间下的所有资源
[root@master ~ 10:04:49]# kubectl create namespace web1
namespace/web1 created
[root@master ~ 10:05:00]# kubectl get ns
NAME STATUS AGE
default Active 4d20h
kube-node-lease Active 4d20h
kube-public Active 4d20h
kube-system Active 4d20h
kubernetes-dashboard Active 4d18h
web-test Active 2d16h
web1 Active 6s
[root@master ~ 10:10:09]# cd test_dir/
[root@master test_dir 10:10:16]# vim create_web2.yaml
apiVersion: v1 # api版本
kind: Namespace # 类型为namespace
metadata: # 定义namespace的元数据
name: web2 # 定义名称为web2
[root@master test_dir 10:11:23]# kubectl apply -f create_web2.yaml
namespace/web2 created
[root@master test_dir 10:12:28]# kubectl get ns
NAME STATUS AGE
default Active 4d20h
kube-node-lease Active 4d20h
kube-public Active 4d20h
kube-system Active 4d20h
kubernetes-dashboard Active 4d18h
web-test Active 2d16h
web1 Active 7m36s
web2 Active 8s
[root@master test_dir 10:12:39]# kubectl delete namespaces web1
namespace "web1" deleted
[root@master test_dir 10:14:09]# kubectl get ns
NAME STATUS AGE
default Active 4d20h
kube-node-lease Active 4d20h
kube-public Active 4d20h
kube-system Active 4d20h
kubernetes-dashboard Active 4d18h
web-test Active 2d16h
web2 Active 108s
YAML文件删除
bash复制代码
[root@master test_dir 10:14:16]# kubectl delete -f create_web2.yaml
namespace "web2" deleted
[root@master test_dir 10:14:50]# kubectl get ns
NAME STATUS AGE
default Active 4d20h
kube-node-lease Active 4d20h
kube-public Active 4d20h
kube-system Active 4d20h
kubernetes-dashboard Active 4d18h
web-test Active 2d16h
