Node roles

[anton-johansson]

In my understanding, some of the policies that descheduler uses to evict pods are based on nodes. Node utilization, for example. I have two different roles in my cluster, worker and nginx. The nginx role will only ever have three pods:

• flannel (or whatever pod networking we use)
• filebeat (gather logs)
• nginx-ingress-controller (handle ingresses)

Wouldn't descheduler always consider those nodes under-utilized? Or does descheduler respect the nodeSelector property of the pods' deployment/statefulset/daemonset?

Or is there a way of configuring which nodes descheduler should look at?

[aveshagarwal]

yes descheuler has a command line flag --node-selector to target only selected nodes.

[anton-johansson]

Cool, I can see that here:
https://github.com/kubernetes-incubator/descheduler/blob/d73471327b6737a3c85b4edd6416b0df654ceaab/cmd/descheduler/app/options/options.go#L56-L57

Thanks!

Is there any "official" documentation for descheduler? Any webpage, wiki-page, or something similar? Or maybe it will be added to Kubernetes official docs whenever #132 is dealt with?

[aveshagarwal]

https://github.com/kubernetes-incubator/descheduler/blob/master/README.md.
Please feel free to send a PR.