6.7

On virtual datastores, all other large-sized files, such as virtual disks, memory snapshots, swap, and
digest, are stored as separate virtual volumes.
Config-VVols are created as 4-GB virtual volumes. Generic content of the config-VVol usually consumes
only a fraction of this 4-GB allocation, so config-VVols are typically thin-provisioned to conserve backing
space. Any additional large files, such as ISO disk images, DVD images, and image files, might cause the
config-VVol to exceed its 4-GB limit. If such files are included in an OVF template, deployment of the VM
OVF to vSphere Virtual Volumes storage fails. If these files are part of an existing VM, migration of that
VM from a traditional datastore to vSphere Virtual Volumes storage also fails.
Solution
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For VM migration. Before migrating a VM from a traditional datastore to a virtual datastore, remove
excess content from the VM home directory to keep the config-VVol under the 4-GB limit.
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For OVF deployment. Because you cannot deploy an OVF template that contains excess files directly
to a virtual datastore, first deploy the VM to a nonvirtual datastore. Remove any excess content from
the VM home directory, and migrate the resulting VM to vSphere Virtual Volumes storage.
Failed Attempts to Migrate VMs with Memory Snapshots to and
from Virtual Datastores
When you attempt to migrate a VM with hardware version 10 or earlier to and from a vSphere Virtual
Volumes datastore, failures occur if the VM has memory snapshots.
Problem
The following problems occur when you migrate a version 10 or earlier VM with memory snapshots:
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Migration of a version 10 or earlier VM with memory snapshots to a virtual datastore is not supported
and causes a failure.
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Migration of a version 10 or earlier VM with memory snapshots from a virtual datastore to a nonvirtual
datastore, such as VMFS, can succeed. If you later make additional snapshots and attempt to
migrate this VM back to vSphere Virtual Volumes storage, your attempt fails.
Cause
vSphere Virtual Volumes storage does not require that you use a particular hardware version for your
virtual machines. Typically, you can move a virtual machine with any hardware version to vSphere Virtual
Volumes storage. However, if you have a VM with memory snapshots, and plan to migrate this VM
between a virtual datastore and a nonvirtual datastore, use the VM of hardware version 11.
Non-VVols virtual machines of hardware version 11 or later use separate files to store their memory
snapshots. This usage is consistent with VMs on vSphere Virtual Volumes storage, where memory
snapshots are created as separate VVols instead of being stored as part of a .vmsn file in the VM home
directory. In contrast, non-VVols VMs with hardware version 10 continue to store their memory snapshots
as part of the .vmsn file in the VM home directory. As a result, you might experience problems or failures
when attempting to migrate these VMs between virtual and nonvirtual datastores.
vSphere Storage
VMware, Inc. 300