Prometheus must be installed first to enable metric collection. The DCGM exporter is then deployed as a DaemonSet (to ensure it runs on every node) and configured, enabling Prometheus to scrape the GPU metrics. Finally, the metrics availability is verified.

All listed components are critical for high availability and fault tolerance. Redundant power and cooling prevent downtime due to failures. High-speed networks ensure continued connectivity. High-capacity storage protects data. Monitoring systems provide early warnings of potential issues, but by themselves, they do not prevent failure. All components are crucial for a truly robust AI data center.

MIG configurations are not persistent by default. The 'nvidia-smi mig -Igip' command can be used to load and save instance placement to persistence DB (Igip) and thus the instances are retained across reboots. If the configuration is not saved, it will be lost after a reboot. The other options are less likely causes of this specific issue.

A firewall provides the necessary security by restricting communication to only the required port and protocol. Opening all ports (A) is insecure. Disabling network access (C) prevents functionality. Relying on defaults (D) is insufficient. VPN is not needed for local communication and overcomplicated. (E)

Data locality minimizes network traffic by allowing compute nodes to access data shards from storage nodes that are physically close to them. Centralized data loading creates a bottleneck. A global namespace simplifies access but doesn't address network traffic. Aggressively caching helps, but relies on data already being transferred initially. A single large file negates the benefits of sharding.