Add admin user for Jenkins to kubeadm kubernetes cluster - jenkins

Question

I created a Kubernetes cluster for a single-master multi-node cluster using kubeadm following the official kubernetes guide:
Kubernetes cluster
I currently connect my laptop to the cluster via this command:
kubectl get nodes --username kubernetes-admin --kubeconfig ~/.kube/config
However, I now want to add a separate user (or same actual user but different name) for our Jenkins to run commands. I just want a separate username for access/logging purposes.
How can I easily add another "jenkins" username (possibly with its own cert) in the config file? Kubeadm automatically uses --authorization-mode=Node (or at least mine did)
Background info: Only people who may make any changes on our cluster currently have/need access, so I don't need to only give users access to certain namespaces etc. Also, keep in mind we will have a cluster per environment: dev, UAT, production, etc.

Answer 1

It's suitable to use Kubernetes serviceAccount and instruct your Jenkins deployment to use that account (with a bound Role):
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: jenkins
---
kind: Role
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: jenkins
rules:
- apiGroups: [""]
resources: ["pods"]
verbs: ["create","delete","get","list","patch","update","watch"]
- apiGroups: [""]
resources: ["pods/exec"]
verbs: ["create","delete","get","list","patch","update","watch"]
- apiGroups: [""]
resources: ["pods/log"]
verbs: ["get","list","watch"]
- apiGroups: [""]
resources: ["secrets"]
verbs: ["get"]
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: RoleBinding
metadata:
name: jenkins
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: jenkins
subjects:
- kind: ServiceAccount
name: jenkins
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
labels:
app: jenkins
name: jenkins
spec:
replicas: 1
selector:
matchLabels:
app: jenkins
template:
metadata:
labels:
app: jenkins
spec:
serviceAccountName: jenkins