Warning: Deactivating this setting may increase metadata locking overhead across your cluster. Use this strictly as a diagnostic step or temporary workaround while working with vendor support. Summary Checklist Diagnostic Area Action Item
Traditionally, when a server needed to update metadata on a shared Logical Unit Number (LUN), it used standard SCSI reservations ( SCSI-2 or SCSI-3 PR ). This locked the entire LUN. While one host updated a file, all other hosts connected to that LUN had to wait, creating massive input/output (I/O) bottlenecks. This locked the entire LUN
This section provides a structured approach to diagnosing and resolving the error. Operations like powering a VM on or off,
Operations like powering a VM on or off, creating a snapshot, vMotion migrations, or cloning vDisks hang indefinitely or fail outright. creating a snapshot
ATS is a storage hardware acceleration feature (part of VAAI) used by ESXi to lock individual disk blocks rather than an entire LUN.
When a system displays the error message it indicates that a low-level synchronization command failed because the storage state changed unexpectedly. This mechanism is critical for maintaining a single source of truth across shared infrastructure. The Underlying Technology: VAAI and ATS