After a firmware upgrade on a DGX H100, the administrator notices that one GPU is...

The first step is to review the firmware update logs and run nvsm show health. After a DGX H100 firmware upgrade, a missing GPU can result from incomplete firmware activation, failed component update, PCIe enumeration failure, GPU tray communication issues, BMC inventory mismatch, or an actual hardware fault. NVSM is the correct DGX platform-level health tool because it checks hardware state across GPUs, NVSwitch components, PCIe devices, storage, power, cooling, and system sensors. Firmware logs are equally important because they show whether each update completed successfully and whether a reboot, cold power cycle, BMC reset, or AC power cycle is still required. Replacing the GPU immediately is premature and may cause unnecessary downtime. Ignoring the issue is unsafe because production AI workloads expect all GPUs to be visible and healthy. Re-running firmware across all components without diagnosis can hide the original failure or introduce more risk. Proper bring-up practice is to collect evidence, verify hardware health, confirm firmware activation state, and then decide whether reseating, power cycling, reapplying firmware, or service escalation is required.