k8s nsenter script

nsenter.sh

#!/bin/sh

node=${1}
kube_context=${2:-""}

nodeName=$(kubectl ${kube_context:+--context $kube_context} get node "$node" -o template --template='{{index .metadata.labels "kubernetes.io/hostname"}}') 
nodeSelector='"nodeSelector": { "kubernetes.io/hostname": "'${nodeName:?}'" },'
podName=$USER-nsenter-$node
kubectl ${kube_context:+--context $kube_context} run "${podName:?}" --restart=Never -it --rm --image overriden --overrides '
{
  "spec": {
    "hostPID": true,
    "hostNetwork": true,
    '"${nodeSelector?}"'
    "tolerations": [{
        "operator": "Exists"
    }],
    "containers": [
      {
        "name": "nsenter",
        "image": "alexeiled/nsenter:2.34",
        "command": [
          "/nsenter", "--all", "--target=1", "--", "su", "-"
        ],
        "stdin": true,
        "tty": true,
        "securityContext": {
          "privileged": true
        }
      }
    ]
  }
}' --attach "$@"

Usage example

$ kubectl --context ctx-xxx get nodes
NAME                        STATUS   ROLES    AGE     VERSION
node-yyy   Ready    <none>   17d    v1.23.6
node-zzz   Ready    <none>   59d     v1.23.6

$ sh nsenter.sh node-yyy ctx-xxx
If you don't see a command prompt, try pressing enter.
root@node-yyy:~#