Virtual machine backup and clone operations are failing due to bad sectors on the vSAN datastore.

Products

• VMware vSAN

Issue/Introduction

Symptoms

• The virtual machine encounters an error message during the cloning process.

         Failed to create object clone /vmfs/volumes/vsan:52aa##-cf7dd####/6228ea##-4c##-b8##-27##-e4434bb####/CloneTest.vmdk with flags 0x3 Input/output error.

Environment

• VMware vSAN 7.x
• VMware vSAN 8.x

Cause

• The following error message appears in the /var/run/log/vobd.log when a virtual machine clone operation fails. Unrecoverable checksum errors, caused by bad sectors on the vSAN disk, are leading to failures in both backup and clone operations.

        2025-03-25T04:59:32.897Z: [vSANCorrelator] 935513093245us: [vob.vsan.dom.unrecoverableerror] vSAN detected an unrecoverable medium or checksum error for component 644e1d64-14##-1d80-df66-############ on disk group 522ff5##-c9##-ca39-c5c8-############.
    2025-03-25T04:59:32.908Z: [vSANCorrelator] 935513104363us: [vob.vsan.dom.unrecoverableerror] vSAN detected an unrecoverable medium or checksum error for component 644e1d64-14##-1d80-df66-############ on disk group 522ff5##-c9##-ca39-c5c8-############.

• Medium errors observed on the physical disk drive are reported in the /var/run/log/vmkernel.log file, indicating potential issues with the disk.

         2025-03-25T04:59:32.897Z cpu2:209805)ScsiDeviceIO: 4176: Cmd(0x45be86a85348) 0x28, CmdSN 0x7cc49cb2 from world 0 to dev"naa.xxxxxxxxxxxxxxxx" failed H:0x0 D:0x2 P:0x0 Valid sense data: 0x3 0x11 0x0 Medium Error, LBA: 1318295282
         2025-03-25T04:59:32.908Z cpu6:2098057)ScsiDeviceIO: 4176: Cmd(0x45bec4adb1c8) 0x28, CmdSN 0x7cc4a797 from world 0 to dev"naa.xxxxxxxxxxxxxxxx" failed  H:0x0 D:0x2 P:0x0 Valid sense data: 0x3 0x11 0x0 Medium Error, LBA: 1318296506

Resolution

• Restore the virtual machine from the latest available backup.The Hardware vendor needs to be contacted for faulty disk drive replacement.
• Create a storage policy with checksum disabled, apply it to the VM, clone the VM, and verify data integrity within the guest OS .

Additional Information

Using vSAN Policies