IBM Support

VMware VAAI Hardware Accelerated Locking is Not Supported With V6.4.0.0 or V6.4.0.1

Flash (Alert)


VMware hosts using the Hardware Accelerated Locking feature of the VAAI API are not supported with V6.4.0.0 or V6.4.0.1, due to an issue that can cause both nodes in a Storwize V70000 or SAN Volume Controller I/O Group to reboot simultaneously, leading to an I/O Group-wide loss of access.


VMware hosts configured to use the Hardware Accelerated Locking feature of the VAAI API employ SCSI Compare and Write to control locking on Storwize V7000 and SAN Volume Controller volumes.

An issue exists in the handling of Compare and Write commands in V6.4.0.0 and V6.4.0.1 releases that can lead to both nodes in a Storwize V7000 or SVC I/O Group rebooting simultaneously, which would cause a loss of access to all volumes presented by this I/O Group.

Customers are advised not to use the Hardware Accelerated Locking feature if they are running V6.4.0.0 or V6.4.0.1.

Please refer to VMware support documentation for instructions on how to disable the Hardware Accelerated Locking feature.


V6.3.0.x and earlier are unaffected by this issue.

This issue was resolved by APAR IC84869 in the V6.4.0.2 PTF release.

Cross reference information
Segment Product Component Platform Version Edition
Storage Virtualization SAN Volume Controller 6.4 SAN Volume Controller 6.4

Document information

More support for: IBM Storwize V7000 (2076)

Version: 6.4

Operating system(s): IBM Storwize V7000

Reference #: S1004134

Modified date: 14 July 2012