Monday, June 4, 2012

Potential DS8000 loss of access with VMWare 4.1 and higher with VAAI Zero Blocks/Write Same enabled

Perhaps a little bit out of my league but nevertheless worth mentioning :


The extended features of VAAI ( Zero Blocks/Write Same ) are not supported by DS8000 at this time, but are enabled by default on ESX 4.1 or higher.


IBM has received reports of issues when running VAAI Zero Blocks/Write Same commands with DS8000 that have caused application problems including a loss of access to data. Clients are advised to disable VAAI's use of the Zero Blocks/Write Same command to avoid the possibility of an issue, and the procedure to do so is described in the Mitigation information below.


To avoid any issues, use the following to disable the Zero Blocks/Write Same function of VAAI (HardwareAcceleratedInit parameter). Other functions of VAAI may remain enabled for use on other storage systems. All OTHER non VAAI features of VMWare ESX 4.1 or higher are certified with DS8000 (all models) and function normally.

Here's a KB for disabling the Zero Blocks/Write Same command. -


IBM is working to address the issues of running VAAI Zero Blocks/Write Same functions with DS8000, and will send an update out when this has been done.

1 comment:

Nitesh Kumar said...

I really appreciate information shared above. It’s of great help. If someone want to learn Online (Virtual) instructor lead live training in IBM Storage Track, kindly contact us Offer World Class Virtual Instructor led training on IBM Storage Track. We have industry expert trainer. We provide Training Material and Software Support. MaxMunus has successfully conducted 100000+ trainings in India, USA, UK, Australlia, Switzerland, Qatar, Saudi Arabia, Bangladesh, Bahrain and UAE etc.
For Demo Contact us.
Nitesh Kumar
Skype id: nitesh_maxmunus
Ph:(+91) 8553912023