kubectl get hpa targets:unknow

Question

I have installed kubeadm. Heapster show me metrics, but hpa no

kubectl get hpa

NAME      REFERENCE          TARGETS          MINPODS   MAXPODS   REPLICAS   AGE

httpd     Deployment/httpd   <unknown> / 2%   2         5         2          19m

kubeadm version

kubeadm version: version.Info{Major:"1", Minor:"6", GitVersion:"v1.6.6", GitCommit:"7fa1c1756d8bc963f1a389f4a6937dc71f08ada2", GitTreeState:"clean", BuildDate:"2017-06-16T18:21:54Z", GoVersion:"go1.7.6", Compiler:"gc", Platform:"linux/amd64"}

docker version

Client:

Version:      1.11.2
 API version:  1.23
 Go version:   go1.5.4
 Git commit:   b9f10c9
 Built:        Wed Jun  1 22:00:43 2016
 OS/Arch:      linux/amd64

Answer 1

You may have had to enable a metrics-server. Heapster is now deprecated. Also make sure you have Kubernetes version greater than 1.7. You can check this buy typing kubectl get nodes.

You can enable the metrics server by looking at the minikube addons.

minikube addons list gives you the list of addons.

minikube addons enable metrics-server enables metrics-server.

Wait a few minutes, then if you type kubectl get hpa the percentage for the TARGETS <unknown> should appear.

Answer 2

I found the solution:

kubectl describe hpa

failed to get cpu utilization: missing request for cpu on container httpd in pod default/httpd-796666570-2h1c6

Change the yaml of deployment and add:

resources:
  requests:
    cpu:400m

Then kubectl describe hpa

failed to get cpu utilization: unable to get metrics for resource cpu: no metrics returned from heapster

Wait a few minutes and all works fine.