Coredns deployment question

jcremp77

Could coredns deployment not being replicated to the master be an issue. When checking on the which nodes were running the coredns, I noticed it was only on worker nodes and not the master. Please see below.

And from looking at the details of the pods I can see that the 'selector' has chosen these nodes due to a value of:
kubernetes.io/os=linux

Furthermore I see the following under 'tolerations'...and it would appear this might be 'why' the master isn't running a 'coredns' pod...am I reading this correctly?

tolerations:
  - key: CriticalAddonsOnly
    operator: Exists
  - effect: NoSchedule
    key: node-role.kubernetes.io/master
  - effect: NoSchedule
    key: node-role.kubernetes.io/control-plane
  - effect: NoExecute
    key: node.kubernetes.io/not-ready
    operator: Exists
    tolerationSeconds: 300
  - effect: NoExecute
    key: node.kubernetes.io/unreachable
    operator: Exists
    tolerationSeconds: 300

Just wondering what the best practice should be. Thanks.