Merge pull request #40996 from matheusjunior/update-node-drain-doc

Add note about `nodeName` ignoring a drained node

Author: k8s-ci-robot

content/en/docs/tasks/administer-cluster/safely-drain-node.md

@@ -60,6 +60,16 @@ and respecting the PodDisruptionBudget you have defined). It is then safe to
 bring down the node by powering down its physical machine or, if running on a
 cloud platform, deleting its virtual machine.
 
+{{< note >}}
+If any new Pods tolerate the `node.kubernetes.io/unschedulable` taint, then those Pods
+might be scheduled to the node you have drained. Avoid tolerating that taint other than
+for DaemonSets.
+
+If you or another API user directly set the [`nodeName`](/docs/concepts/scheduling-eviction/assign-pod-node/#nodename)
+field for a Pod (bypassing the scheduler), then the Pod is bound to the specified node
+and will run there, even though you have drained that node and marked it unschedulable.
+{{< /note >}}
+
 First, identify the name of the node you wish to drain. You can list all of the nodes in your cluster with
 
 ```shell