You are setting up a Kubernetes cluster on NVIDIA DGX systems using BCM, and you need to initialize the control-plane nodes. What is the most…

The Kubernetes scheduler determines the best available node to place a pod on. If swap is enabled, and a pod's memory usage exceeds its defined limit, the host OS could swap parts of the pod's memory to disk. This behavior is unpredictable and can severely degrade performance and stability, which contradicts Kubernetes' goal of resource management and predictable scheduling. Therefore, the kubelet is designed not to start if swap is detected. The kubeadm init command runs a series of preflight checks that will fail if swap is enabled, preventing the control-plane initialization from proceeding. This makes disabling swap a mandatory and critical prerequisite.

A. A load balancer is essential for a high-availability (HA) control plane, but it is not a prerequisite for initializing a single control-plane node. Disabling swap is a fundamental requirement for any node.

C. Kubernetes requires a CRI-compliant container runtime (e.g., containerd, CRI-O). Specifying Docker is incorrect as the dockershim component was removed in Kubernetes v1.24, making containerd the typical runtime in modern deployments.

D. Control-plane nodes need IP addresses for intra-cluster communication, but these do not need to be external IPs. The API server endpoint, often on a load balancer, is what typically requires external accessibility.

1. Kubernetes Official Documentation: In the guide for installing the kubeadm toolchain, it is explicitly stated as a mandatory step before beginning.

Source: Kubernetes Documentation, "Installing kubeadm".

Reference: In the "Before you begin" section, under "Verify that your machines meet the requirements," the documentation states: "You MUST disable swap in order for the kubelet to work properly." (https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/install-kubeadm/)

2. NVIDIA Base Command Platform Documentation: NVIDIA's official deployment guide for its platforms, which use BCM (Bright Cluster Manager), specifies disabling swap as a necessary step for preparing Kubernetes nodes.

Source: NVIDIA Base Command Platform Deployment Guide v3.0

Reference: Chapter 5, "Installing Kubernetes," Section "Preparing the Kubernetes Nodes," Step 1: "Disable swap on all Kubernetes nodes."

3. NVIDIA DGX SuperPOD Deployment Guide: This guide, relevant to DGX systems, reinforces the same prerequisite for setting up Kubernetes clusters.

Source: NVIDIA DGX SuperPOD with NVIDIA AI Enterprise Deployment Guide

Reference: Chapter 4, "Software Installation and Configuration," Section "Preparing the Kubernetes Nodes," Step 1: "Disable swap on all Kubernetes nodes."