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Table Of Contents
Storage vMotion is subject to the following requirements and limitations:
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Virtual machine disks must be in persistent mode or be raw device mappings (RDMs). For virtual
compatibility mode RDMs, you can migrate the mapping file or convert to thick-provisioned or thin-
provisioned disks during migration if the destination is not an NFS datastore. If you convert the
mapping file, a new virtual disk is created and the contents of the mapped LUN are copied to this
disk. For physical compatibility mode RDMs, you can migrate the mapping file only.
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Migration of virtual machines during VMware Tools installation is not supported.
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Because VMFS3 datastores do not support large capacity virtual disks, you cannot move virtual disks
greater than 2 TB from a VMFS5 datastore to a VMFS3 datastore.
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The host on which the virtual machine is running must have a license that includes Storage vMotion.
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ESXi 4.0 and later hosts do not require vMotion configuration to perform migration with Storage
vMotion.
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The host on which the virtual machine is running must have access to both the source and target
datastores.
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For limits on the number of simultaneous migrations with vMotion and Storage vMotion, see Limits on
Simultaneous Migrations.
CPU Compatibility and EVC
vCenter Server performs compatibility checks before it allows migration of running or suspended virtual
machines to ensure that the virtual machine is compatible with the target host.
vMotion transfers the running state of a virtual machine between underlying ESXi systems. Live migration
requires that the processors of the target host provide the same instructions to the virtual machine after
migration that the processors of the source host provided before migration. Clock speed, cache size, and
number of cores can differ between source and target processors. However, the processors must come
from the same vendor class (AMD or Intel) to be vMotion compatible.
Note Do not add virtual ESXi hosts to an EVC cluster. ESXi virtual machines are not supported in EVC
clusters.
Migrations of suspended virtual machines also require that the virtual machine be able to resume
execution on the target host using equivalent instructions.
When you initiate a migration with vMotion or a migration of a suspended virtual machine, the Migrate
Virtual Machine wizard checks the destination host for compatibility. If compatibility problems prevent
migragion, the wizard displays an error message.
The CPU instruction set available to the operating system and to applications running in a virtual machine
is determined at the time that a virtual machine is powered on. This CPU feature set is based on the
following items:
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Host CPU family and model
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Settings in the BIOS that might disable CPU features
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