kubernetes - 授予 Kubernetes 服务帐户权限以从所有命名空间获取 pod

Question

我想授予 Kubernetes 服务帐户执行 kubectl --token $token get pod --all-namespaces 的权限。我很熟悉为单个命名空间执行此操作，但不知道如何为所有命名空间执行此操作(包括将来可能创建的新命名空间并且不授予服务帐户 full admin privileges )。

目前我收到此错误消息:

Error from server (Forbidden): pods is forbidden: User "system:serviceaccount:kube-system:test" cannot list resource "pods" in API group "" at the cluster scope

需要什么(集群)角色和角色绑定(bind)？

更新 使用以下ClusterRoleBinding 将角色view 分配给服务是可行的，是向前迈出的一步。但是，我想进一步将服务帐户的权限限制在所需的最低限度。

kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: test
subjects:
- kind: ServiceAccount
  name: test
  namespace: kube-system
roleRef:
  kind: ClusterRole
  name: view
  apiGroup: rbac.authorization.k8s.io

可以按如下方式提取服务帐户的 token :

secret=$(kubectl get serviceaccount test -n kube-system -o=jsonpath='{.secrets[0].name}')
token=$(kubectl get secret $secret -n kube-system -o=jsonpath='{.data.token}' | base64 --decode -)

Answer 1

1. 遵循以下 yaml 并创建测试服务帐户。

apiVersion: v1
kind: ServiceAccount
metadata:
  name: test
  namespace: default

kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: pod-reader
rules:
- apiGroups: [""]
  resources: ["pods"]
  verbs: ["get", "list", "watch"]


kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: test
subjects:
- kind: ServiceAccount
  name: test
  namespace: default
roleRef:
  kind: ClusterRole
  name: pod-reader
  apiGroup: rbac.authorization.k8s.io

从下面的示例中部署测试 pod

apiVersion: v1
kind: Pod
metadata:
  labels:
    run: test
  name: test
spec:
  serviceAccountName: test
  containers:
  - args:
    - sleep
    - "10000"
    image: alpine
    imagePullPolicy: IfNotPresent
    name: test
    resources:
      requests:
        memory: 100Mi

1. 安装 curl 和 kubectl

kubectl exec test apk add curl
kubectl exec test -- curl -o /bin/kubectl https://storage.googleapis.com/kubernetes-release/release/v1.12.0/bin/linux/amd64/kubectl
kubectl exec test -- sh -c 'chmod +x /bin/kubectl'

1. 您应该能够列出来自测试 pod 的所有命名空间的 pod

master $ kubectl exec test -- sh -c 'kubectl get pods --all-namespaces'
NAMESPACE     NAME                             READY   STATUS    RESTARTS   AGE
app1          nginx-6f858d4d45-m2w6f           1/1     Running   0          19m
app1          nginx-6f858d4d45-rdvht           1/1     Running   0          19m
app1          nginx-6f858d4d45-sqs58           1/1     Running   0          19m
app1          test                             1/1     Running   0          18m
app2          nginx-6f858d4d45-6rrfl           1/1     Running   0          19m
app2          nginx-6f858d4d45-djz4b           1/1     Running   0          19m
app2          nginx-6f858d4d45-mvscr           1/1     Running   0          19m
app3          nginx-6f858d4d45-88rdt           1/1     Running   0          19m
app3          nginx-6f858d4d45-lfjx2           1/1     Running   0          19m
app3          nginx-6f858d4d45-szfdd           1/1     Running   0          19m
default       test                             1/1     Running   0          6m
kube-system   coredns-78fcdf6894-g7l6n         1/1     Running   0          33m
kube-system   coredns-78fcdf6894-r87mx         1/1     Running   0          33m
kube-system   etcd-master                      1/1     Running   0          32m
kube-system   kube-apiserver-master            1/1     Running   0          32m
kube-system   kube-controller-manager-master   1/1     Running   0          32m
kube-system   kube-proxy-vnxb7                 1/1     Running   0          33m
kube-system   kube-proxy-vwt6z                 1/1     Running   0          33m
kube-system   kube-scheduler-master            1/1     Running   0          32m
kube-system   weave-net-d5dk8                  2/2     Running   1          33m
kube-system   weave-net-qjt76                  2/2     Running   1          33m