FC LUNs fails to create VMFS datastore if ATS locking is disabled

Products

• VMware vCenter Server

Issue/Introduction

A lun presented using FC controller faces issue with creating a new datastore with below error:

VMkernel.log

2025-10-28T12:37:17.569Z In(182) vmkernel: cpu50:2099168 opID=3d8d5050)LVM: 14441: Deleting device <naa.xxxxxxxxxxx:1>dev OpenCount: 0, postRescan: True
 
2025-10-28T13:43:48.505Z In(182) vmkernel: cpu77:2098325)ScsiDeviceIO: 4686: Cmd(0x45da3976e800) 0x16, CmdSN 0x91a8ec from world 0 to dev "naa.xxxxxxxxxxxx" failed H:0x0 D:0x2 P:0x0 Valid sense data: 0x5 0x20 0x0
2025-10-28T13:43:48.506Z In(182) vmkernel: cpu55:2099168 opID=eec09413)FSS: 2514: Failed to create FS on dev [naa.xxxxxxxxxxx:1] fs [Datastore_Test] type [vmfs6] fbSize 1048576 => Not supported
2025-10-28T13:48:37.729Z In(182) vmkernel: cpu1:2097744)NMP: nmpDeviceCancelIOUpdateResv:48: Prepare to update reservation for device "naa.xxxxxxxxxxxx" over the newly selected path "vmhba3:C0:T15:L30".

Environment

ESXi 8.0

Cause

ATS locking scheme disabled. Go to the Host Configuration and check for "VMFS3/HardwareAcceleratedLocking", if set to "0" it is Disabled.

Resolution

Enable the ATS Locking scheme 

Host --> Configuration --> VMFS3/HardwareAcceleratedLocking
To enable, set the value to "1"

Additional Information

ATS locking needs to be consistent across all hosts - mixed mode locking can lead to data corruption. The configuration on other devices/hosts should be reviewed before making this change, to ensure there will be no impact.