ESXi Host Unresponsive Due to Machine Check Exception (MCE) Hardware Faults
Article ID: 449212
Updated On:
Products
Issue/Introduction
The ESXi host becomes unresponsive, leading to virtual machine disconnection and loss of management via vCenter Server. While the physical console/DCUI may remain visible, it does not respond to keyboard input (F2/F12).
- Host status shows as
Not RespondingorDisconnectedin vCenter. - Direct Console User Interface (DCUI) is unresponsive to local input.
- Logs stop abruptly or contain repetitive hardware-related error events.
vobd.log shows messages similar to:
[cpuCorrelator] <timestamp>: [vob.cpu.mce.log#] MCE bank 3: status:0x##########`
System event logs show similar errors to:
Assert + Processor Configuration ErrorMCACOD (architectural) 0x#### = Cache Hierarchy: Level 1 Instruction Cache InstructionFetch Error
Environment
- VMware ESXi 8.x
Cause
The unresponsiveness is caused by persistent physical hardware faults, specifically Machine Check Exceptions (MCE).
Log analysis indicates Level 1 Instruction Cache errors (InstructionFetch Error) and thousands of "Processor Configuration Error" entries in the System Event Log (SEL). These are hardware-level architectural errors.
Resolution
To resolve this issue, the underlying hardware faults must be addressed through firmware updates and hardware vendor engagement.
- Engage Hardware Vendor:
- Provide the hardware System Event Logs (SEL) and the decoded MCE errors from the ESXi `vobd.log` to your hardware vendor (e.g., Cisco, Dell, HPE). Request a thorough diagnostic of the CPU and motherboard/system board.
- Provide the hardware System Event Logs (SEL) and the decoded MCE errors from the ESXi `vobd.log` to your hardware vendor (e.g., Cisco, Dell, HPE). Request a thorough diagnostic of the CPU and motherboard/system board.
- Update System BIOS/Firmware:
- Apply the latest firmware bundle provided by the vendor to address known stability issues and processor configuration errata.
- Apply the latest firmware bundle provided by the vendor to address known stability issues and processor configuration errata.
- Validate Component Health:
- If firmware updates do not resolve the MCE events, work with the vendor to identify and replace faulty hardware components (typically the CPU or memory modules associated with the reported MCE bank).
- If firmware updates do not resolve the MCE events, work with the vendor to identify and replace faulty hardware components (typically the CPU or memory modules associated with the reported MCE bank).
- If the host is currently in a hung state:
- Perform a hard power cycle/reset via the Baseboard Management Controller (BMC/iManage).
- Place the host into Maintenance Mode immediately upon reboot to prevent production virtual machines from running on potentially unstable hardware until the vendor completes the hardware review.
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