Running Kubernetes Pods without the Kubernetes Scheduler

I am on my continuous preparation for Kubernetes and during this process I find interesting capabilities I did not know about. (See another article from the same series)

One of them is the capability to run a Pod on a node without the running Scheduler (when the Scheduler is running it will apply it’s algorithms to put the Pod on the optimal Node for it.)

This is possible by using the nodeSelector field.

The example bellow shows how this can be used.

By using this technique the Pod will run on the Node named cluster2-master1 without the cluster Scheduler.

kind: Pod

metadata:

  labels:

    name: manual-schedule

spec:

  nodeName: cluster2-master1        # use the node name here

  containers:

  - image: httpd:2.4-alpine

    imagePullPolicy: IfNotPresent

    name: manual-schedule