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Moif_Murphy
Enthusiast
Enthusiast
‎12-05-2012 07:18 AM

Disabling VAAI / Fujitsu Eternus DX90 S1

Hi,

We're having disk latency issues when performing cloning and other such like activities during the day. Usual scenario, we need to get something cloned or migrated and the task gets to around 11% and stays there for a while. Phone goes, users complain about their Outlook not responding, task abandoned.

I went on the VMware 5 ICM course last week where I learnt about VAAI and upon further research it appears that our SAN doesn't support VAAI. Even further research took me to this page: http://www.elasticsky.de/2012/08/vsphere-und-vaai/

My question is, if we disable VAAI then what are the farther reaching connotations of doing so? The website lists:

What are the functions VAAI?

  • Atomic Test & Set (ATS) - An improved method of LUN reservation compared to SCSI Reservations.
  • Clone block, Full Copy, XCOPY - eg, placement of a VM from the template will be delegated to the storage array
  • Zero block - filling disk sectors with zeros
  • Thin Provisioning
  • Block Delete

Will we lose all of this if we disable the fuction?

Thanks!

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1 Reply
jbilly2002
Contributor
Contributor
‎12-22-2012 11:19 AM

Why would VAAI be the reason for your cloning issues ? If anything VAAI should improve cloning performance.

If VAAI isn't supported by your array, you dont need to do anything to disable it. Take a look at http://kb.vmware.com/kb/1021976

A quick google search on your array model  led me to http://www.fujitsu.com/global/services/computing/storage/eternus/tools/. It seems that there is a VAAI plugin for your array. However do check with Fujitsu before trying it out.

To answer your question, it is possible to individually disable VAAI features - http://kb.vmware.com/kb/1033665

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