H206954: Data corruption issue using XCOPY in VAAI (VMware ESXI 5.xx) - IBM System Storage DCS3700, DS3512, DS3524


RETAIN tip: H206954


Data corruption has been reported when using VMware ESXi 5.xx with vStorage API for Array Integration (VAAI) hardware accelerated Virtual Machine File System (VMFS) data movement enabled on IBM System Storage DS3500 and DCS3700 Storage Controllers.

The issue occurs when XCOPY is utilized to improve performance on the following VMware operations:

  - Storage vMotion
- VM cloning
- VM snapshots

Any of the affected models and code levels (shown as follows) running with VMware ESXi 5.xx hosts with VAAI enabled and performing Storage vMotion, VM cloning, or VMware snapshots likely are exposed to undetected data corruption during these operations.

Affected configurations

The system may be any of the following IBM storage controllers:

  • IBM System Storage DCS3700 Storage Subsystem, type 1818, any model
  • IBM System Storage DS3512, type 1746, any model
  • IBM System Storage DS3524, type 1746, any model

This tip is not software specific.

This tip is not option specific.

The 7.83.xx.xx firmware for the DS3500 and DCS3700 is affected.


This behavior has been corrected in the release and later of the System Storage controller firmware.

The file is or will be available by selecting the appropriate Product Group, type of System, Product name, Product machine type, and Operating system on IBM Support's Fix Central web page, at the following URL:


Until the referenced release of firmware containing the fix has been installed, users potentially exposed to this issue should disable the portion of VAAI on the vSphere server that uses XCOPY on the storage controller, using the following ESXi command:

  esxcfg-advcfg -s 0 /DataMover/HardwareAcceleratedMove

This disables only hardware acceleration of these VMware operations; the basic operations still will function properly. Once the hardware acceleration is disabled, the possibility of data corruption from this issue is eliminated.

Additional information

A modification to the storage controller firmware has been made which corrects this issue.

If the instructions in the Workaround section to disable the hardware acceleration are executed, once the updated storage controller firmware version has been deployed, re-enable the hardware acceleration by using the following command:

  esxcfg-advcfg -s 1 /DataMover/HardwareAcceleratedMove

Applicable countries and regions


Document id:  MIGR-5091874
Last modified:  2012-12-06
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