It could cause problem when vmotion is moving the VSA and meanwhile there are IOs sending to the VSA. In the worst case it could damage the system data, and make VSA unrecoverable. However, cold migrate (migrate VSA after power it off) is supported.

I wondered about this today, and looked at the March 2018 version of the UnityVSA white paper. It says:

Supported Storage vMotion - Storage vMotion can be used to migrate Dell EMC UnityVSA or its virtual disks as long as the VM is offline. VMware High Availability (HA) - VMware HA is highly recommended to restart Dell EMC UnityVSA in case of host failure vMotion - vMotion can be used to migrate Dell EMC UnityVSA to another host as long as the VM is offline.

I think it's saying that offline VM migration of the UnityVSA is supported. Offline migration is not Storage vMotion or vMotion.

Storage vMotion and vMotion by definition refer to migrating a VM while that VM is online. The fact that these terms are listed under the Supported heading is confusing. They should be listed under the Not Recommended or Not Supported section.  Wei Chen can you consider updating the white paper for improved clarity?

You are correct. I can look to make this change during the next revision of the white paper.

Thanks for the feedback!