k8s中kubeconfig的配置及使用
作者:互联网
1、概述
kubeconfig文件保存了k8s集群的集群、用户、命名空间、认证的信息。kubectl命令使用kubeconfig文件来获取集群的信息,然后和API server进行通讯。
注意:用于配置对集群的访问的文件称为kubecconfig文件。也就是说,kubeconfig文件中包含的内容是集群的配置。但是,并不是必须有个文件名字叫kubeconfig
默认情况下,kubectl命令从$HOME/.kube目录下查找一个名字叫做config的文件。可以通过KUBECONFIG环境变量或者--kubeconfig参数来指定其他的kubeconfig文件。
kubeconfig中主要由如下部分组成:
- clusters (集群)
- users(用户)
- context(上下文)
2、kubeconfig支持多集群、多用户、多认证
在实际的使用中的如下场景:
- kubelet使用证书认证(kubelet和api server进行认证)
- 用户使用token进行认证
- 管理员为不同的用户提供不同的证书
都可以使用kubeconfig来组织起集群、用户、命名空间的信息。同样,也可以使用context在集群和命名空间之间进行切换。
3、Context的定义
在kubeconfig中,context中将访问一个集群的参数进行分组。访问这个context名称就是访问这个参数组。context就是一组信息的别名,举例来说,当在高德中使用家的地址,公司的地址就是一个别名,就能迅速的定位到具体的地址信息。
每个context都有3个参数:
- cluster (集群)
- namespace(命名空间)
- user(用户)
默认情况下,kubectl命令从current context中来获取参数,然后与集群进行通讯。
4、查看kubeconfig的配置
如果有KUBECONFIG环境变量,看到的配置是合并的配置
[root@nccztsjb-node-11 ~]# kubectl config view
apiVersion: v1
clusters:
- cluster:
certificate-authority-data: DATA+OMITTED
server: https://k8s.apiserver.io:6443
name: cluster.local
contexts:
- context:
cluster: cluster.local
user: kubernetes-admin-cluster.local
name: kubernetes-admin-cluster.local@cluster.local
current-context: kubernetes-admin-cluster.local@cluster.local
kind: Config
preferences: {}
users:
- name: kubernetes-admin-cluster.local
user:
client-certificate-data: REDACTED
client-key-data: REDACTED
[root@nccztsjb-node-11 ~]#
通过kubectl config view得到的配置可能是来自一个kubeconfig文件,也可能是来自多个kubeconfig文件合并的结果。
5、kubeconfig设置
5.1、设置集群
(1)集群有CA认证,并且将证书的输入嵌入到配置文件中
kubectl config --kubeconfig=config-demo set-cluster development --server=https://1.2.3.4 --embed-certs --certificate-authority=ca.crt
指定--kubeconfig参数后,所有的配置都会写到对应的文件中。如果不指定--kubeconfig参数那么就会将配置文件写到~/.kube/config这个文件中。
--certificate-authority后面是ca证书的路径,需要确保这个证书是存在的。
查看config-demo文件的内容
[root@nccztsjb-node-11 config-exercise]# cat config-demo
apiVersion: v1
clusters:
- cluster:
certificate-authority-data: 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
server: https://1.2.3.4
name: development
contexts: null
current-context: ""
kind: Config
preferences: {}
users: null
[root@nccztsjb-node-11 config-exercise]#
已经设置好了集群
(2)集群没有证书的
kubectl config --kubeconfig=config-demo set-cluster development --server=https://1.2.3.4
查看证书内容
[root@nccztsjb-node-11 config-exercise]# kubectl config --kubeconfig=config-demo set-cluster development --server=https://1.2.3.4
Cluster "development" set.
[root@nccztsjb-node-11 config-exercise]# cat config-demo
apiVersion: v1
clusters:
- cluster:
server: https://1.2.3.4
name: development
contexts: null
current-context: ""
kind: Config
preferences: {}
users: null
[root@nccztsjb-node-11 config-exercise]
(3)集群有证书,但是证书验证的
kubectl config --kubeconfig=config-demo set-cluster scratch --server=https://5.6.7.8 --insecure-skip-tls-verify
查看证书的内容
[root@nccztsjb-node-11 config-exercise]# cat config-demo
apiVersion: v1
clusters:
- cluster:
certificate-authority-data: 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
server: https://1.2.3.4
name: development
- cluster:
insecure-skip-tls-verify: true
server: https://5.6.7.8
name: scratch
contexts: null
current-context: ""
kind: Config
preferences: {}
users: null
[root@nccztsjb-node-11 config-exercise]#
(4)删除集群
kubectl config --kubeconfig=config-demo unset clusters.development
5.2、设置用户
(1)设置用户,使用客户端的证书和客户端密钥,并且将证书数据嵌入到配置文件中
kubectl config --kubeconfig=config-demo set-credentials developer --client-certificate=fake-cert-file --client-key=fake-key-seefile --embed-certs=true
注意:客户端证书和key必须要存在。
(2)设置用户,使用用户名和密码
kubectl config --kubeconfig=config-demo set-credentials experimenter --username=exp --password=some-password
(3)删除用户
kubectl config --kubeconfig=config-demo unset users.experimenter
experimenter这个就是使用set-credentials参数后面的名字。
5.3、增加上下文信息context
kubectl config --kubeconfig=config-demo set-context dev-frontend --cluster=development --namespace=frontend --user=developer
设置context将集群、命名空间、用户进行分组。即在dev-fronted这个context的以developer用户的信息访问developement集群的frontend命名空间。
kubectl config --kubeconfig=config-demo set-context dev-storage --cluster=development --namespace=storage --user=developer
dev-stroage这个context访问stroage命名空间。
查看通过以上的所有配置形成的kubeconfig文件
[root@nccztsjb-node-11 config-exercise]# cat config-demo
apiVersion: v1
clusters:
- cluster:
certificate-authority: fake-ca-file
server: https://1.2.3.4
name: development
- cluster:
insecure-skip-tls-verify: true
server: https://5.6.7.8
name: scratch
contexts:
- context:
cluster: development
namespace: frontend
user: developer
name: dev-frontend
- context:
cluster: development
namespace: storage
user: developer
name: dev-storage
- context:
cluster: scratch
namespace: default
user: experimenter
name: exp-scratch
current-context: ""
kind: Config
preferences: {}
users:
- name: developer
user:
client-certificate: fake-cert-file
client-key: fake-key-seefile
- name: experimenter
user:
password: some-password.
username: exp
5.4、设置当前的context
kubectl config --kubeconfig=config-demo use-context dev-frontend
查看当前的context
kubectl config --kubeconfig=config-demo current-context
5.5、只查看和当前context有关的配置信息
kubectl config --kubeconfig=config-demo view --minify
[root@nccztsjb-node-11 config-exercise]# kubectl config --kubeconfig=config-demo view --minify
apiVersion: v1
clusters:
- cluster:
certificate-authority: fake-ca-file
server: https://1.2.3.4
name: development
contexts:
- context:
cluster: development
namespace: frontend
user: developer
name: dev-frontend
current-context: dev-frontend
kind: Config
preferences: {}
users:
- name: developer
user:
client-certificate: fake-cert-file
client-key: fake-key-seefile
那么kubeconfig中的其他的信息就不会显示
5.6、查看配置中所有的context
[root@nccztsjb-node-11 config-exercise]# kubectl config --kubeconfig=config-demo get-contexts
CURRENT NAME CLUSTER AUTHINFO NAMESPACE
* dev-frontend development developer frontend
dev-storage development developer storage
exp-scratch scratch experimenter default
ok,以上就是kubeconfig的基本配置和使用。
6、总结
主要就是2个概念,kubeconfig由集群、用户、context组成。context将集群、命名空间、用户进行分组。每个context对应一个环境信息。
标签:--,demo,配置,kubeconfig,cluster,context,k8s,config 来源: https://www.cnblogs.com/chuanzhang053/p/15817997.html