Question:
You have two nodes: ik8s-master-0 and ik8s-node-0. You need to set up a Kubernetes cluster using kubeadm.
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Configure ik8s-master-0 as the master node.
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Join ik8s-node-0 to the cluster as a worker node.
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Use the --ignore-preflight-errors=all option with all kubeadm commands.
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Perform all tasks by SSH’ing into the respective nodes.
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After completing, return to the base node (node-1).
Which sequence of commands and steps below correctly accomplishes this?
✅ Correct Answer: A
Explanation:
The correct choice is Option A because:
1. kubeadm init with Preflight Error Ignoring:
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Uses kubeadm init --ignore-preflight-errors=all, which is mandatory for this task.
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Ensures the control plane is initialized even if the system has unmet preflight conditions.
2. Sets Up Kubeconfig Properly:
3. Uses Correct Join Command:
4. Follows All Node and SSH Instructions:
❌ Why Other Options Are Incorrect
🔸 Option B
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Does not include the required --ignore-preflight-errors=all on either the master or worker node.
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Violates task instruction: “Any kubeadm invocations will require the use of the –ignore-preflight-errors=all option.”
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Would result in a failed or blocked installation in environments with unmet prerequisites.
🔸 Option C
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Initializes the master node correctly with the ignore flag but misses the required token and discovery hash in the kubeadm join command.
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kubeadm join <master-ip>:6443 --ignore-preflight-errors=all is incomplete and would fail without those parameters.
🔸 Option D
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Similar to Option A but introduces an extra flag: --pod-network-cidr=10.244.0.0/16.
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While this CIDR is used with some CNI plugins like Flannel, it was not part of the instructions and could result in misconfiguration if not aligned with the CNI plugin in use.
✅ Correct Answer: A
Explanation:
The correct choice is Option A because:
1. kubeadm init with Preflight Error Ignoring:
-
Uses kubeadm init --ignore-preflight-errors=all, which is mandatory for this task.
-
Ensures the control plane is initialized even if the system has unmet preflight conditions.
2. Sets Up Kubeconfig Properly:
3. Uses Correct Join Command:
4. Follows All Node and SSH Instructions:
❌ Why Other Options Are Incorrect
🔸 Option B
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Does not include the required --ignore-preflight-errors=all on either the master or worker node.
-
Violates task instruction: “Any kubeadm invocations will require the use of the –ignore-preflight-errors=all option.”
-
Would result in a failed or blocked installation in environments with unmet prerequisites.
🔸 Option C
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Initializes the master node correctly with the ignore flag but misses the required token and discovery hash in the kubeadm join command.
-
kubeadm join <master-ip>:6443 --ignore-preflight-errors=all is incomplete and would fail without those parameters.
🔸 Option D
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Similar to Option A but introduces an extra flag: --pod-network-cidr=10.244.0.0/16.
-
While this CIDR is used with some CNI plugins like Flannel, it was not part of the instructions and could result in misconfiguration if not aligned with the CNI plugin in use.