6.7

Table Of Contents
Performance Best Practices
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Encryption performance depends on the CPU and storage speed.
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Encrypting existing virtual machines is more time consuming than encrypting a virtual machine during
creation. Encrypt a virtual machine when you create it if possible.
Storage Policy Best Practices
Do not modify the bundled VM Encryption sample storage policy. Instead, clone the policy and edit the
clone.
Note No automated way of returning VM Encryption Policy to its original settings exists.
See the vSphere Storage documentation for details customizing storage policies.
Virtual Machine Encryption Caveats
Review Virtual Machine Encryption caveats to avoid problems later.
To understand which devices and features cannot be used with Virtual Machine Encryption, see Virtual
Machine Encryption Interoperability.
Limitations
Consider the following caveats when you plan your virtual machine encryption strategy.
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When you clone an encrypted virtual machine or perform a Storage vMotion operation, you can
attempt to change the disk format. Such conversions do not always succeed. For example, if you
clone a virtual machine and attempt to change the disk format from lazy-zeroed thick format to thin
format, the virtual machine disk keeps the lazy-zeroed thick format.
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When you detach a disk from a virtual machine, the storage policy information for the virtual disk is
not retained.
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If the virtual disk is encrypted, you must explicitly set the storage policy to VM Encryption Policy
or to a storage policy that includes encryption.
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If the virtual disk is not encrypted, you can change the storage policy when you add the disk to a
virtual machine.
See Virtual Disk Encryption for details.
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Decrypt core dumps before moving a virtual machine to a different cluster.
The vCenter Server does not store KMS keys but only tracks the key IDs. As a result, vCenter Server
does not store the ESXi host key persistently.
Under certain circumstances, for example, when you move the ESXi host to a different cluster and
reboot the host, vCenter Server assigns a new host key to the host. You cannot decrypt any existing
core dumps with the new host key.
vSphere Security
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