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Affinity, taints, and tolerations

The scheduler picks a node on its own, but often you need to intervene: this pod must be on an SSD node, two replicas shouldn't share a machine, that node is for one team. This article digs into three tools for steering the scheduler — nodeAffinity (pull a pod toward labeled nodes), podAntiAffinity (push pods apart), taint/toleration (a node pushes pods away unless tolerated). Tested for real: a pod stuck on affinity, a third with nowhere to go, one evicted by NoExecute.