WARNING: CpuSched: XXXX: processor apparently halted for XXXX ms

While I have seen people discuss this error message and solution, I figured it would be a good idea to discuss in terms of specific configurations such as on Cisco hardware and VMware virtualization. I feel this is important to understand the implications of the error message and to express the importance of BIOS configurations.

First, the issue: Cisco UCS B230-M2 blades (dual 10-core = 20 ‘processors’) running ESXi were throwing processor halted log messages. While this in itself may or may not be an issue, under little load via VMware clone operations ESXi hosts were disconnecting from vCenter Server (vCS) and becoming unresponsive for several minutes. Further digging uncovered that when the ESXi host disconnected from vCS the logs shows that all processors on the host were halting at exactly the same time.

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