forbidden: User , "code": 403 error while accessing kube-apiserver using curl

Kubernetes version : v1.19.0

I have created a user and performed clusterrolebinding with a role cluster-admin.

[root@project1-master ~]# kubectl describe clusterrole cluster-admin
Name:         cluster-admin
Labels:       kubernetes.io/bootstrapping=rbac-defaults
Annotations:  rbac.authorization.kubernetes.io/autoupdate: true
PolicyRule:
  Resources  Non-Resource URLs  Resource Names  Verbs
  ---------  -----------------  --------------  -----
  *.*        []                 []              [*]
             [*]                []              [*]

[root@project1-master ~]# kubectl describe clusterrolebinding sajeesh  cluster-admin
Name:         sajeesh
Labels:       <none>
Annotations:  <none>
Role:
  Kind:  ClusterRole
  Name:  cluster-admin
Subjects:
  Kind  Name     Namespace
  ----  ----     ---------
  User  sajeesh


Name:         cluster-admin
Labels:       kubernetes.io/bootstrapping=rbac-defaults
Annotations:  rbac.authorization.kubernetes.io/autoupdate: true
Role:
  Kind:  ClusterRole
  Name:  cluster-admin
Subjects:
  Kind   Name            Namespace
  ----   ----            ---------
  Group  system:masters

I am able to run kubectl with this useraccount and get pods information :

[root@project1-master ~]# kubectl get pods --as sajeesh
NAME    READY   STATUS    RESTARTS   AGE
busyb   1/1     Running   3          21h

But when i try to access kube-apiserver using curl it show forbidden error as following :

[root@project1-master ~]# curl --cacert /etc/kubernetes/pki/ca.crt --cert sajeesh.crt --key sajeesh.key https://$IP:6443/api/v1/namespaces/default/pods/busyb
{
  "kind": "Status",
  "apiVersion": "v1",
  "metadata": {

  },
  "status": "Failure",
  "message": "pods \"busyb\" is forbidden: User \"system:anonymous\" cannot get resource \"pods\" in API group \"\" in the namespace \"default\"",
  "reason": "Forbidden",
  "details": {
    "name": "busyb",
    "kind": "pods"
  },
  "code": 403

I have re-verified the cacert , cert & key i am providing with that user account .They are correct.

Any suggestions why this is happening and how to fix it.

Solution

finally managed to findout the problem.it is not related to kubernetes but with curl command i am using .

curl --cacert /etc/kubernetes/pki/ca.crt --cert sajeesh.crt --key sajeesh.key https://$IP:6443/api/v1/namespaces/default/pods/busyb

when i used -v switch along with command , It showed :

* Initializing NSS with certpath: sql:/etc/pki/nssdb
*   CAfile: /etc/kubernetes/pki/ca.crt
  CApath: none
* warning: certificate file name "sajeesh.crt" handled as nickname; please use "./sajeesh.crt" to force file name
* NSS: client certificate not found: newsajeesh.crt
* SSL connection using TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384

So basically it was looking for absolute path as input for arguments --cert & --key

curl --cacert /etc/kubernetes/pki/ca.crt --cert ./sajeesh.crt --key ./sajeesh.key https://$IP:6443/api/v1/namespaces/default/pods/busyb

after giving the absolute path it worked fine and i am able to get the output.