Atomic Test And Set Of Disk Block Returned False For Equality [work] < Free Access >
This error message typically appears in VMware ESXi logs (such as vmkernel.log) and indicates a failure in the Atomic Test and Set (ATS) locking mechanism, which is part of the vSphere Storage APIs for Array Integration (VAAI). What it Means
Observed Issue
If you are seeing this error in your system logs, follow these steps to isolate the cause: Check Storage Logs Look for SCSI Sense Codes (e.g., H:0x0 D:0x2 P:0x0 Valid). This error message typically appears in VMware ESXi
Here’s a good, clear review for that scenario, depending on who your audience is: clear review for that scenario
This means the storage engine performed the atomic operation, but the validation step failed. Specifically: but the validation step failed. Specifically: