Using OpenShift 3.1/K8 1.1 and given a pod that has already been created with/without a nodeSelector. I.e.
apiVersion: v1
kind: Pod
metadata:
generateName: blah-
labels:
name: blah
spec:
containers:
image: some/image
name: blah-image
ports:
- containerPort: 8080
nodeSelector: # can you add this after this pod has been created?
region: infraIs it possible to change/add a nodeSelector?
Similar to the way you add/modify labels
You can change it in the associated ReplicationController (if any) but not in the definition of a running Pod. If you edit the RC as suggested the Pod itself must be recreated in order to start on the selected node(s).
In OpenShift if you are using a deployment config (the predecessor to Kube's Deployment object) you can edit your DC and add them. On the cli it's:
oc edit dc/NAMEThat will trigger a rolling update that creates a new RC and scales down the old, unlabeled pods.