How to get the resource usage of a pod in Kubernetes?

Question

How can we get the real resource usage (not resource requests) of each pod on Kubernetes by command line? Heapster is deprecated. Meanwhile, Metrics-server still does not support kubectl top pod.

1. Heapster -

   I deployed Heapster using the following command

   $ heapster/deploy/kube.sh start
   kubectl get pods --all-namespaces
   NAMESPACE     NAME                                                           READY     STATUS    RESTARTS   AGE
   kube-system   calico-node-hlcbl                                              2/2       Running   0          39m
   kube-system   calico-node-m8jl2                                              2/2       Running   0          35m
   kube-system   coredns-78fcdf6894-bl94w                                       1/1       Running   0          39m
   kube-system   coredns-78fcdf6894-fwx95                                       1/1       Running   0          39m
   kube-system   etcd-ctl.kube.yarnrm-pg0.utah.cloudlab.us                      1/1       Running   0          39m
   kube-system   heapster-84c9bc48c4-qzt8x                                      1/1       Running   0          15s
   kube-system   kube-apiserver-ctl.kube.yarnrm-pg0.utah.cloudlab.us            1/1       Running   0          39m
   kube-system   kube-controller-manager-ctl.kube.yarnrm-pg0.utah.cloudlab.us   1/1       Running   0          38m
   kube-system   kube-proxy-nj9f8                                               1/1       Running   0          35m
   kube-system   kube-proxy-zvr2b                                               1/1       Running   0          39m
   kube-system   kube-scheduler-ctl.kube.yarnrm-pg0.utah.cloudlab.us            1/1       Running   0          39m
   kube-system   monitoring-grafana-555545f477-jldmz                            1/1       Running   0          15s
   kube-system   monitoring-influxdb-848b9b66f6-k2k4f                           1/1       Running   0          15s
   

   When I used kubectl top, I encountered the following errors.

   $ kubectl top pods
   Error from server (ServiceUnavailable): the server is currently unable to handle the request (get services http:heapster:)
   $ kubectl top nodes
   Error from server (ServiceUnavailable): the server is currently unable to handle the request (get services http:heapster:)
   

2. metrics-server:

   metrics-server has not supported kubectl top Resource Metrics API

If anyone already solved the same problem, please help me. Thanks.

Answer 1

Error from server (ServiceUnavailable): the server is currently unable to handle the request (get services http:heapster:)

It sounds like the heapster deployment just forgot to install the Service for heapster; I would expect this would get you past that error, but unknown whether it would actually cause kubectl top pods to start to work:

kubectl create -f /dev/stdin <<SVC
apiVersion: v1
kind: Service
metadata:
  name: heapster
  namespace: kube-system
spec:
  selector:
    whatever-label: is-on-heapster-pods
  ports:
  - name: http
    port: 80
    targetPort: whatever-is-heapster-is-listening-on
SVC