Tag: microk8s

Working with the kubernetes dashboard

[ Yes, headlamp is a better choice for this ]

Sometimes when you are working with microk8s, you may want to run the Kubernetes dashboard. We first enable it with microk8s enable dashboard. We assume that we have microk8s enable rbac and microk8s enable metrics-server already. The dashboard pod runs in the kube-system namespace.

To access the dashboard we now create a service account which will be used for logging into the system: kubectl -n kube-system create sa kubernetes-dashboard-george

We bind this account to the cluster-admin role:

# kubectl -n kube-system create token kubernetes-dashboard-george
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: kubernetes-dashboard-george
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: kubernetes-dashboard-george
  namespace: kube-system

We apply this with something like kubectl apply -f kubernetes-dashboard-george.yaml

And now we can request a login token to access the dashboard with kubectl -n kube-system create token kubernetes-dashboard-george

We are almost there. Within the cluster we can run the port-forward command kubectl -n kube-system port-forward --address=0.0.0.0 svc/kubernetes-dashboard 8443:443

And now all that is left, is to access the dashboard. Assuming one of our machines has the IP address 172.31.1.13 we can use the nip.io trick and get to https://ip-172.31.1.13.nip.io:8443/#/pod?namespace=default

microk8s, nginx ingress and X-Forwarded-For

Sometimes when you run microk8s in AWS, you may want to have an application load balancer in front. Such configurations mess around with the value of the header X-Forwarded-For regardless of whether the append attribute is present on the load balancer. By reading the nginx ingress documentation, you need to edit the ConfigMap resource and add proxy-real-ip-cidr and use-forwarded-headers. You may also set compute-full-forwarded-for.

It only remains to figure out the name of the ConfigMap when ingress is installed with microk8s enable ingress. It is named nginx-load-balancer-microk8s-conf :

apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-load-balancer-microk8s-conf
  namespace: ingress
data:
  proxy-real-ip-cidr: 172.31.0.0/16
  use-forwarded-headers: "true"