ESXi host upgrade hangs at "VMK init 53/192: SMP_Boot_APs"

Products

• VMware vSphere ESXi 8.0

Issue/Introduction

While upgrading ESXi host from 8.0U3e to U3i the upgrade process hangs. The host initialization progress stuck at the following stage:

VMK init (53/192): SMP_Boot_APs

Environment

ESXi 8.x

Cause

This hang occurs during the Symmetric Multi-Processing (SMP) boot phase. It indicates a synchronization failure between the ESXi kernel and the processor cores. This is typically caused by localized hardware configuration issues, corrupted BIOS settings, or a requirement for firmware updates to support the kernel initialization of the specific ESXi build.

Resolution

1. Check BIOS Compatibility: 
   • Verify your server hardware and current BIOS version against the VMware Compatibility Guide.
2. Update Firmware: 
   • Apply the latest available BIOS and firmware updates from your hardware vendor. 
3. Temporary Workaround: 
   • Try disabling Hyper-Threading in the BIOS settings. If the host boots successfully with this disabled, it confirms a synchronization issue that usually requires a BIOS update to fix permanently.
4. Hardware Check: 
   • If BIOS updates do not resolve the hang, please consult your hardware vendor to ensure there are no underlying physical CPU or motherboard issues.

Additional Information

Japanese version of this KB : https://knowledge.broadcom.com/external/article/446621