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VMware VAAI integration

Hello,
I came across a problem whereby VMs in Vmware 6.5 would not storage vmotion from one PetaSan LUN running VMFS 5 to another running VMFS 6. My favorite search tool was able to locate another person having the same issue and they ended up disabling VAAI on each ESXi host. Then I got to reading up more about just how Vmware's "space reclimation" feature works in VMFS 6 and it apparently needs VAAI enabled AND a plugin that speaks to the SAN to accomplish this. Queried our PetaSAN mounts and see the plugin field for this blank.

Given that VAAI had to be disabled for storage vmotion to work, I imagine the error presented when it was enabled was related to not being able to communicate with SAN. Is anyone else having this problem? Is there a plugin from underlying community projects being used by PetaSAN for iSCSI that can be installed on VMware to get this working?
Steps Taken to disable VAAI:
https://itcp.freshdesk.com/support/solutions/articles/190923-disabling-the-vaai-functionality-in-esxi-esx-1033665-

Simple Tutorial on how Space Reclamation works: https://www.youtube.com/watch?v=9XX8S6gsuTk
naa.60014050000800000000000000000000
VAAI Plugin Name:
ATS Status: supported
Clone Status: supported
Zero Status: supported
Delete Status: supported

naa.60014050000700000000000000000000
VAAI Plugin Name:
ATS Status: supported
Clone Status: supported
Zero Status: supported
Delete Status: supported

naa.60014050000200000000000000000000
VAAI Plugin Name:
ATS Status: supported
Clone Status: supported
Zero Status: supported
Delete Status: supported

Brian Jankovich

1) The VMFS5/6 is probably not a PetaSAN issue. As far as we are concerned, they are 2 different iSCSI disks that can receive xcopy block level commands to copy data internally. It is most probably a VMFS5/6 compatability issue. Do you know if this works on other SANs ?

2) One special requirement we have for vmotion to work well (as per our guide) is to have all paths for both datastores to be served by the same set of PetaSAN iSCSI nodes. If source disk is served on PetaSAN nodes A,B, then destination should also have its paths on nodes A,B. Use the path assignment page to move paths if required. If this is not met, vmotion should work but will be much slower and maybe get timeout errors.

3) Space reclamation VAAI works out of the box in PetaSAN. If you want to disable vmotion but keep reclamation, you should be able to edit /opt/petasan/config/tuning/current/lio_tunings and set emulate_3pc to 0, then reconnect paths. Note that even if you do disable space reclamaction, VMWare will res-use that space when needed, so it is not lost space.

Quote from admin on March 26, 2020, 4:12 pm

 

2) One special requirement we have for vmotion to work well (as per our guide) is to have all paths for both datastores to be served by the same set of PetaSAN iSCSI nodes. If source disk is served on PetaSAN nodes A,B, then destination should also have its paths on nodes A,B. Use the path assignment page to move paths if required. If this is not met, vmotion should work but will be much slower and maybe get timeout errors.

In the event that source  and target disks are on different petasan clusters... Might that cause any issue?

 

vmotion VAAI is meant for hardware acceleration for moving data within a single system. If there are on different systems, the performance will be low.