使用TOKEN授权访问api-server在k8s运维场景中比较常见，
apiserver有三种级别的客户端认证方式
1，HTTPS证书认证：基于CA根证书签名的双向数字证书认证方式
2，HTTP Token认证：通过一个Token来识别合法用户
3，HTTP Base认证：通过用户名+密码的认证方式
通常的运维场景使用第二种Token较为方便Token的权限是关联service account,
# kubectl describe secrets admin-token-2q28f -n kube-systemName: admin-token-2q28f
Namespace: kube-system
Labels: <none>
Annotations: kubernetes.io/service-account.name: adminkubernetes.io/service-account.uid: 93316ffa-7545-11e9-b617-00163e06992d
Type: kubernetes.io/service-account-token
Data
====
ca.crt: 1419 bytes
namespace: 11 bytes
token: eyJhbGciOiJ******Service Account 的权限来自Clusterrolebinding-->ClusterRole
# kubectl describe serviceaccount admin -n kube-systemName: admin
Namespace: kube-system
Labels: <none>
Annotations: kubectl.kubernetes.io/last-applied-configuration:{"apiVersion":"v1","kind":"ServiceAccount","metadata":{"annotations":{},"name":"admin","namespace":"kube-system"}}
Image pull secrets: <none>
Mountable secrets: admin-token-2q28f
Tokens: admin-token-2q28f
Events: <none>通过clusterrolebinding 可以拿到ClusterRole对应的rolename
# kubectl get clusterrolebinding admin -o yamlapiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:annotations:kubectl.kubernetes.io/last-applied-configuration: |{"apiVersion":"rbac.authorization.k8s.io/v1beta1","kind":"ClusterRoleBinding","metadata":{"annotations":{},"name":"admin"},"roleRef":{"apiGroup":"rbac.authorization.k8s.io","kind":"ClusterRole","name":"cluster-admin"},"subjects":[{"kind":"ServiceAccount","name":"admin","namespace":"kube-system"}]}creationTimestamp: 2019-05-13T06:08:49Zname: adminresourceVersion: "1523"selfLink: /apis/rbac.authorization.k8s.io/v1/clusterrolebindings/adminuid: 93356439-7545-11e9-b617-00163e06992d
roleRef:apiGroup: rbac.authorization.k8s.iokind: ClusterRolename: cluster-admin
subjects:
- kind: ServiceAccountname: adminnamespace: kube-system这个role是什么权限?
# kubectl get clusterrole cluster-admin -o yamlapiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:annotations:rbac.authorization.kubernetes.io/autoupdate: "true"creationTimestamp: 2019-05-13T06:01:10Zlabels:kubernetes.io/bootstrapping: rbac-defaultsname: cluster-adminresourceVersion: "55"selfLink: /apis/rbac.authorization.k8s.io/v1/clusterroles/cluster-adminuid: 817e2b9e-7544-11e9-9766-00163e0e34c8
rules:
- apiGroups:- '*'resources:- '*'verbs:- '*'
- nonResourceURLs:- '*'verbs:- '*'从clusterrole权限来看，admin关联的权限还是比较大的，正常的集群运维中建议根据自身的真实需要，去定制权限
https://kubernetes.io/docs/reference/access-authn-authz/rbac/
了解完这些，分享一个小技巧，这样后面客户再有curl访问apiserver的需求，我相信你没问题了！
# kubectl describe secrets $(kubectl get secrets -n kube-system |grep admin |cut -f1 -d ' ') -n kube-system |grep -E '^token' |cut -f2 -d':'|tr -d '\t'|tr -d ' 'eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUiOiJhZG1pbi10b2tlbi0ycTI4ZiIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50Lm5hbWUiOiJhZG1pbiIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50LnVpZCI6IjkzMzE2ZmZhLTc1NDUtMTFlOS1iNjE3LTAwMTYzZTA2OTkyZCIsInN1YiI6InN5c3RlbTpzZXJ2aWNlYWNjb3VudDprdWJlLXN5c3RlbTphZG1pbiJ9.EQzj2LsWn2k31m-ksn9GmB1bZTi1Xjw1fnmWFgRKlwhS2QAaVnDXfV_TgUovpq5oWKh7h0gTVaNaK4KKK76yAv6GfMehpOdIO5xHCfQAWVRhla1cwUDC64tz7vJ1zGcx_lz4hKfhdXN1T8FYS0B0hf3h2OloAMfCZTzDjRWz24GVwH-WRTEwY_5tav65GiZzBTsnz1vV7NOcx-Kl8AK2HbowtBYqK05x7oOmp84FiQMwpYU-7g0c03h61zev4lvf0e-HFtqKiByPi8gD-uiVRvE-xayOz5oIESWw2GfhzfNf_uyR7eLplCKUBecVMtwVsBauNaeqU-IIJW5VIHAOxw
# TOKEN=$(kubectl describe secrets $(kubectl get secrets -n kube-system |grep admin |cut -f1 -d ' ') -n kube-system |grep -E '^token' |cut -f2 -d':'|tr -d '\t'|tr -d ' ')# kubectl config view |grep server|cut -f 2- -d ":" | tr -d " "https://192.168.0.130:6443
# APISERVER=$(kubectl config view |grep server|cut -f 2- -d ":" | tr -d " ")
使用curl访问apiserver
# curl -H "Authorization: Bearer $TOKEN" $APISERVER/api --insecure{"kind": "APIVersions","versions": ["v1"],"serverAddressByClientCIDRs": [{"clientCIDR": "0.0.0.0/0","serverAddress": "192.168.0.130:6443"}]
}
原文链接
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