K8s 资源混乱怎么办？Namespace 隔离 + 上下文切换实战
- [Namespace and Contexts](#Namespace and Contexts)
-
- [Namespace 介绍](#Namespace 介绍)
- [Namespace 管理](#Namespace 管理)
- [Namespace 切换](#Namespace 切换)
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- [kubernetes 自带工具](#kubernetes 自带工具)
- kubens-第三方工具
- 自定义脚本
- [Cluster 切换](#Cluster 切换)
-
- [~/.kube/config 详解](#~/.kube/config 详解)
- 多集群切换
-
- [kubernetes 自带工具](#kubernetes 自带工具)
- kubectx-第三方工具
Namespace and Contexts
摘要：本文全面介绍了 Kubernetes 中 Namespace 和 Context 的概念、管理与切换方法。首先解释了 Namespace 的作用------将物理集群逻辑划分为多个隔离的资源集合，并介绍了默认的四个 Namespace。接着详细展示了 Namespace 的创建、查看、编辑和删除操作，以及如何在特定 Namespace 中操作资源。然后讲解了 Namespace 切换的三种方式：Kubernetes 自带工具、第三方工具 kubens 和自定义脚本。最后深入探讨了 Cluster 切换，包括 kubeconfig 文件结构解析、单集群与多集群配置，以及使用 kubectl 自带工具和第三方工具 kubectx 进行集群切换的实践方法。
学习参考：Namespace
Namespace 介绍
**问题：**多个用户使用同一个Kubernetes Cluster， 如何将他们创建的资源隔离开呢？
答案：Namespace ，简写ns，也称之为 project，代表资源集合，用于分组集群资源。Kubernetes 使用 Namespace 可以将一个物理的 Cluster 逻辑上划分成多个资源集合， 每个集合就是一个Namespace。 不同Namespace 里的资源是完全隔离的。
Kubernetes 默认创建以下Namespace：
- default： 创建资源时如果不指定Namespace， 将被放到这个Namespace中。
- kube-system： Kubernetes 自己创建的系统资源将放到这个Namespace中。
- kube-public：该命名空间中所有对象可以被所有用户（包括未验证身份的用户）读取。
- kube-node-lease：该命名空间含有与每个节点关联的Lease对象。节点租用允许kubelet发送heartbeat（心跳），以便控制平面能检测节点故障。
思考：所有对象都属于 Namespace 吗?
**答：**大多数Kubernetes资源（例如 pod、services、pvc等）都属于某个Namespace，但 Namespace 资源本身并不在 Namespace 中，更低级别资源（如Node和persistentVolumes）也不在任何Namespace中。
Namespace 管理
bash
# 查看Namespace清单
root@master30:~# kubectl get ns #kubectl get namespaces # 完整写法
NAME STATUS AGE
default Active 7d4h
kube-node-lease Active 7d4h
kube-public Active 7d4h
kube-system Active 7d4h
# 获取Namespace资源yaml格式定义文件
root@master30:~# kubectl get ns default -o yaml
# 创建Namespace
root@master30:~# kubectl create ns laoma
# 注意：命名空间名称满足正则表达式[a-z0-9]([-a-z0-9]*[a-z0-9])?，最大长度为63位
# 直接编辑Namespace
root@master30:~# kubectl edit ns laoma
# 查看Namespace详细信息
root@master30:~# kubectl describe ns laoma
Name: laoma
Labels: <none>
Annotations: <none>
Status: Active
No resource quota.
No LimitRange resource.
# 删除Namespace
root@master30:~# kubectl delete ns laoma
namespace "laoma" deleted
# 注意：
# 删除一个namespace会自动删除该namespace中所有资源。
# default和kube-system命名空间不可删除。Namespace 还可以通过 yaml 文件创建。
yaml
# ns-laoma.yaml
apiVersion: v1
kind: Namespace
metadata:
name: laoma
bash
root@master30:~# kubectl apply -f ns-laoma.yaml
namespace/laoma created操作特定ns中对象，需要使用选项-n指定ns，例如：
bash
# 在laoma ns创建nginx pod
root@master30:~# kubectl run web --image=nginx -n laoma
pod/web created
# 查看laoma下所有pod，同时输出节点/IP
root@master30:~# kubectl get pod -n laoma -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
web 1/1 Running 0 39s 10.224.113.129 worker32.laoma.cloud <none> <none>
root@master30:~# curl -s 10.224.113.129 | grep nginx
<title>Welcome to nginx!</title>
<h1>Welcome to nginx!</h1>
<p>If you see this page, nginx is successfully installed and working.
<a href="https://nginx.org/">nginx.org</a>.<br/>
<a href="https://community.nginx.org/">community.nginx.org</a>.<br/>
<a href="https://f5.com/nginx">f5.com/nginx</a>.</p>
<p><em>Thank you for using nginx.</em></p>Namespace 切换
kubernetes 自带工具
查看当前所在ns
bash
# 查看所有上下文，显示当前默认ns
root@master30:~# kubectl config get-contexts
CURRENT NAME CLUSTER AUTHINFO NAMESPACE
* kubernetes-admin@kubernetes kubernetes kubernetes-admin出列说明：
- CURRENT：*代表当前正在使用的上下文
- NAME：上下文名称（集群 + 用户组合）
- CLUSTER：集群地址标识
- AUTHINFO：认证用户
- NAMESPACE：该上下文绑定的默认命名空间，空 = default
此时NAMESPACE列对应的属性为空，不属于任何NAMESPACE。
设置默认ns
bash
# 修改当前上下文的默认命名空间为laoma
root@master30:~# kubectl config set-context --current --namespace=laoma
Context "kubernetes-admin@kubernetes" modified.
root@master30:~# kubectl config get-contexts
CURRENT NAME CLUSTER AUTHINFO NAMESPACE
* kubernetes-admin@kubernetes kubernetes kubernetes-admin laoma此时，NAMESPACE 列对应的属性为 laoma。
kubens-第三方工具
kubens 安装
bash
# 下载kubens二进制到系统全局命令目录
root@master30:~# wget http://192.168.46.200/class/course-materials/softwares/stage03/kubens -O /usr/local/bin/kubens
# 添加执行权限
root@master30:~# chmod +x /usr/local/bin/kubens
# 配置补全
root@master30:~# wget http://192.168.46.200/class/course-materials/softwares/stage03/kubens.bash -O /etc/bash_completion.d/kubens.bash
# 加载补全，立即生效
root@master30:~# source /etc/bash_completion.d/kubens.bashkubens 命令使用
bash
root@master30:~# kubens -h
USAGE:
kubens : list the namespaces in the current context
kubens <NAME> : change the active namespace of current context
kubens - : switch to the previous namespace in this context
kubens -c, --current : show the current namespace
kubens -h,--help : show this message
root@master30:~# kubens
default
kube-node-lease
kube-public
kube-system
laoma
root@master30:~# kubens kube-system
root@master30:~# kubectl config get-contexts
CURRENT NAME CLUSTER AUTHINFO NAMESPACE
* kubernetes-admin@kubernetes kubernetes kubernetes-admin kube-syste
root@master30:~# kubectl get pods
NAME READY STATUS RESTARTS AGE
calico-kube-controllers-7cb4fd5784-dqv6n 1/1 Running 0 19m
calico-node-5k2bp 1/1 Running 0 18m
calico-node-6vpt6 1/1 Running 0 19m
calico-node-7x82d 1/1 Running 0 19m
coredns-66f779496c-h89xx 1/1 Running 0 19m
coredns-66f779496c-zqqxd 1/1 Running 0 19m
etcd-master30.laoma.cloud 1/1 Running 2 19m
kube-apiserver-master30.laoma.cloud 1/1 Running 2 19m
kube-controller-manager-master30.laoma.cloud 1/1 Running 2 19m
kube-proxy-7l9pr 1/1 Running 0 19m
kube-proxy-9djwp 1/1 Running 0 19m
kube-proxy-n2bk9 1/1 Running 0 18m
kube-scheduler-master30.laoma.cloud 1/1 Running 2 19m自定义脚本
bash
#!/bin/bash
function usage(){
echo "$0 [namespace]
1. 没有namespace参数时，显示namespace清单
2. namespace必须是集群中存在的namespace"
}
# 获取当前namespace
namespace=$(kubectl config get-contexts | awk '/\*/{print $5}')
if [ -z "$namespace" ];then
namespace=default
fi
# 显示 namespace清单
if [ $# -eq 0 ];then
kubectl get ns | awk '{print " "$1}' | sed "s/^ $namespace/\* $namespace/"
exit 1
fi
# 切换 namespace
if [ $# -eq 1 ];then
if kubectl get ns | awk '$1 !~ "NAME" {print $1}' | grep -qx "$1" &>/dev/null;then
kubectl config set-context --current --namespace $1 > /dev/null
echo "当前namespace设置为：$1"
else
usage
fi
fiCluster 切换
~/.kube/config 详解
单集群配置
获取凭据文件内容（不显示敏感信息）：
bash
# 查看kubeconfig，隐藏证书密钥明文
root@master30:~# kubectl config view
yaml
apiVersion: v1
clusters:
- cluster:
certificate-authority-data: DATA+OMITTED
server: https://10.1.8.30:6443
name: kubernetes
contexts:
- context:
cluster: kubernetes
namespace: kube-system
user: kubernetes-admin
name: kubernetes-admin@kubernetes
current-context: kubernetes-admin@kubernetes
kind: Config
preferences: {}
users:
- name: kubernetes-admin
user:
client-certificate-data: DATA+OMITTED
client-key-data: DATA+OMITTED配置文件示例：
yaml
apiVersion: v1
clusters:
- cluster:
certificate-authority-data: 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
server: https://10.1.8.30:6443
name: kubernetes
contexts:
- context:
cluster: kubernetes
user: kubernetes-admin
name: kubernetes-admin@kubernetes
current-context: kubernetes-admin@kubernetes
kind: Config
preferences: {}
users:
- name: kubernetes-admin
user:
client-certificate-data: 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
client-key-data: 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说明：
- certificate-authority-data 指定CA证书，通过base64编码。
bash
# 解码base64证书，查看原始证书内容
root@master30:~# echo 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 | base64 -d
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE------ client-certificate-data 指定用户证书，同样是 base64 编码。
- client-key-data 指定用户私钥，同样是 base64 编码。
bash
# 或者使用以下命令获取不显示具体证书和key内容
root@master30:~# kubectl config view
yaml
apiVersion: v1
clusters:
- cluster:
certificate-authority-data: DATA+OMITTED
server: https://10.1.8.30:6443
name: kubernetes
contexts:
- context:
cluster: kubernetes
user: kubernetes-admin
name: kubernetes-admin@kubernetes
current-context: kubernetes-admin@kubernetes
kind: Config
preferences: {}
users:
- name: kubernetes-admin
user:
client-certificate-data: REDACTED
client-key-data: REDACTED多集群配置
示例：/root/multi-cluster-config
yaml
apiVersion: v1
clusters:
- cluster:
certificate-authority-data: DATA+OMITTED
server: https://10.1.8.30:6443
name: cluster1
- cluster:
certificate-authority-data: DATA+OMITTED
server: https://10.1.8.150:6443
name: cluster2
contexts:
- context:
cluster: cluster1
namespace: default
user: cluster1-admin
name: cluster1-context
- context:
cluster: cluster2
namespace: default
user: cluster2-admin
name: cluster2-context
current-context: cluster1-context
kind: Config
preferences: {}
users:
- name: cluster1-admin
user:
client-certificate-data: DATA+OMITTED
client-key-data: DATA+OMITTED
- name: cluster2-admin
user:
client-certificate-data: DATA+OMITTED
client-key-data: DATA+OMITTED配置文件定义了以下资源：
- clusters：集群信息，包括集群名、authority、地址和端口。
- users：用户信息，包括用户名、certificate和key。
- contexts：上下文信息，包括上下文名称、集群名、用户名和namespace。
多集群切换
kubernetes 自带工具
环境准备：
bash
root@master30:~# cp .kube/config .kube/config.ori
root@master30:~# cp multi-cluster-config .kube/config查看集群清单
bash
# 查看所有集群名称
root@master30:~# kubectl config get-clusters
NAME
cluster1
cluster2查看上下文清单
bash
# 查看全部上下文（区分当前生效集群）
root@master30:~# kubectl config get-contexts
CURRENT NAME CLUSTER AUTHINFO NAMESPACE
* cluster1-context cluster1 cluster1-admin default
cluster2-context cluster2 cluster2-admin default* 代表当前使用的上下文
切换上下文
bash
# 切换到指定上下文（切换集群）
root@master30:~# kubectl config use-context cluster2-context
root@master30:~# kubectl config get-contexts
CURRENT NAME CLUSTER AUTHINFO NAMESPACE
cluster1-context cluster1 cluster1-admin default
* cluster2-context cluster2 cluster2-admin defaultkubectx-第三方工具
kubectx 安装
bash
root@master30:~# wget http://192.168.46.200/class/course-materials/softwares/stage03/kubectx -O /usr/local/bin/kubectx
root@master30:~# chmod +x /usr/local/bin/kubectx
# 配置补全
root@master30:~# wget http://192.168.46.200/class/course-materials/softwares/stage03/kubectx.bash -O /etc/bash_completion.d/kubectx.bash
root@master30:~# source /etc/bash_completion.d/kubectx.bashkubectx 帮助
bash
root@master30:~# kubectx -h
USAGE:
kubectx : list the contexts
kubectx <NAME> : switch to context <NAME>
kubectx - : switch to the previous context
kubectx -c, --current : show the current context name
kubectx <NEW_NAME>=<NAME> : rename context <NAME> to <NEW_NAME>
kubectx <NEW_NAME>=. : rename current-context to <NEW_NAME>
kubectx -d <NAME> [<NAME...>] : delete context <NAME> ('.' for current-context)
(this command won't delete the user/cluster entry
that is used by the context)
kubectx -u, --unset : unset the current context
kubectx -h,--help : show this message
bash
kubectx # 列出所有上下文（集群）
kubectx cluster2-context # 切换到指定集群上下文
kubectx - # 切回上一个集群
kubectx -c / --current # 打印当前使用的集群上下文名
kubectx newname=oldname # 重命名上下文
kubectx newname=. # 给当前上下文重命名
kubectx -d ctx1 ctx2 # 删除指定上下文（不会删除集群/用户配置）
kubectx -u # 清空current-context，不绑定任何集群
kubectx -h # 帮助kubectx 命令使用
bash
root@master30:~# kubectx
cluster1-context
cluster2-context
root@master30:~# kubectx -c
cluster2-context
root@master30:~# kubectx cluster1-context
Switched to context "cluster1-context".
root@master30:~# kubectx -c
cluster1-context
root@master30:~# kubectx -u
Unsetting current context.
Property "current-context" unset.
root@master30:~# kubectx -c
error: current-context is not set