6.5.1

Table Of Contents
MAC Address Management During Migration Between vCenter Server Systems
When you move a virtual machine between vCenter Server instances, the environment specically handles
MAC address migration to avoid address duplication and loss of data in the network.
In an environment with multiple vCenter Server instances, when a virtual machine is migrated, its MAC
addresses are transferred to the target vCenter Server. The source vCenter Server adds the MAC addresses
to a black list so that it does not assign them to newly created virtual machines.
To reclaim unused MAC addresses from the black list, contact VMware Technical Support for assistance.
Migration with Storage vMotion
With Storage vMotion, you can migrate a virtual machine and its disk les from one datastore to another
while the virtual machine is running. With Storage vMotion, you can move virtual machines o of arrays for
maintenance or to upgrade. You also have the exibility to optimize disks for performance, or to transform
disk types, which you can use to reclaim space.
You can choose to place the virtual machine and all its disks in a single location, or you can select separate
locations for the virtual machine conguration le and each virtual disk. The virtual machine does not
change execution host during a migration with Storage vMotion.
During a migration with Storage vMotion, you can change the disk provisioning type.
Migration with Storage vMotion changes virtual machine les on the destination datastore to match the
inventory name of the virtual machine. The migration renames all virtual disk, conguration, snapshot,
and .nvram les. If the new names exceed the maximum lename length, the migration does not succeed.
Storage vMotion has several uses in administering virtual infrastructure, including the following examples
of use.
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Storage maintenance and reconguration. You can use Storage vMotion to move virtual machines o a
storage device to allow maintenance or reconguration of the storage device without virtual machine
downtime.
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Redistributing storage load. You can use Storage vMotion to redistribute virtual machines or virtual
disks to dierent storage volumes to balance capacity or improve performance.
Storage vMotion Requirements and Limitations
A virtual machine and its host must meet resource and conguration requirements for the virtual machine
disks to be migrated with Storage vMotion.
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 le or convert to thick-provisioned or thin-
provisioned disks during migration if the destination is not an NFS datastore. If you convert the
mapping le, 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 le 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 conguration to perform migration with Storage
vMotion.
vCenter Server and Host Management
124 VMware, Inc.