CC00018.CloudKubernetes——|Kubernetes&RBAC介绍.V01|——|命名空间|

一、集群的安全机制

二、k8s集群安全机制-rbac实现鉴权

一、创建一个命名空间

### --- 创建一个命名空间

[root@k8s-master ~]# kubectl get ns
NAME              STATUS   AGE
default           Active   3d23h
kube-node-lease   Active   3d23h
kube-public       Active   3d23h
kube-system       Active   3d23h

[root@k8s-master ~]# kubectl create ns roledemo
namespace/roledemo created
 
[root@k8s-master ~]# kubectl get ns
roledemo          Active   3s

### --- 在新创建的命名空间下创建一个pod

[root@k8s-master ~]# kubectl run nginx --image=nginx -n roledemo
pod/nginx created  
[root@k8s-master ~]# kubectl get pods -n roledemo
NAME    READY   STATUS         RESTARTS   AGE
nginx   0/1     ErrImagePull   0          59s

### --- 创建角色，将rbac-role.yaml该文件上传到服务器

[root@k8s-master ~]# cat rbac-role.yaml 
kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  namespace:roledemo                                # 命名空间的名称和刚才创建的一致
  name: pod-reader
rules:
- apiGroups: [""] # "" indicates the core API group
  resources: ["pods"]
  verbs: ["get", "watch", "list"]                   # 权限

[root@k8s-master ~]# kubectl apply -f rbac-role.yaml 
role.rbac.authorization.k8s.io/pod-reader created

~~~     查看创建的角色

[root@k8s-master ~]# kubectl get role -n roledemo   
NAME         CREATED AT
pod-reader   2021-02-23T08:03:31Z

### --- 创建角色绑定过程

[root@k8s-master ~]# cat rbac-rolebinding.yaml 
kind: RoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: read-pods
  namespace: roledemo
subjects:
- kind: User
  name: mary                            # Name is case sensitive
  apiGroup: rbac.authorization.k8s.io
roleRef:
  kind: Role                            # this must be Role or ClusterRole
  name: pod-reader                      # this must match the name of the Role or ClusterRole you wish to bind to
  apiGroup: rbac.authorization.k8s.io

[root@k8s-master ~]# kubectl apply -f rbac-rolebinding.yaml 
rolebinding.rbac.authorization.k8s.io/read-pods created

~~~     查看绑定结果

[root@k8s-master ~]# kubectl get role,rolebinding -n roledemo
NAME                                        CREATED AT
role.rbac.authorization.k8s.io/pod-reader   2021-02-23T08:03:31Z

NAME                                              ROLE              AGE
rolebinding.rbac.authorization.k8s.io/read-pods   Role/pod-reader   94s

### --- 使用证书来识别它的身份，将rabc-user.sh该文件上传到服务器

[root@k8s-master ~]# mkdir mary
[root@k8s-master ~]# cd mary/
cat > mary-csr.json <

cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes mary-csr.json | cfssljson -bare mary

kubectl config set-cluster kubernetes \
  --certificate-authority=ca.pem \
  --embed-certs=true \
  --server=https://10.10.10.11:6443 \
  --kubeconfig=mary-kubeconfig

kubectl config set-credentials mary \
  --client-key=mary-key.pem \
  --client-certificate=mary.pem \
  --embed-certs=true \
  --kubeconfig=mary-kubeconfig

kubectl config set-context default \
  --cluster=kubernetes \
  --user=mary \
  --kubeconfig=mary-kubeconfig

kubectl config use-context default --kubeconfig=mary-kubeconfig

### --- 执行脚本文件，将证书文件拷贝到当前目录
[root@k8s-master mary]# bash rabc-user.sh

~~~     会多出两个文件
[root@k8s-master mary]# ls                  
mary-csr.json  mary-kubeconfig

~~~     里面有证书信息
[root@k8s-master mary]# cat mary-kubeconfig 

~~~     什么也查看不到，是使用rbac的方式创建的。
[root@k8s-master mary]# kubectl get svc -n roledemo 
No resources found in roledemo namespace.