Top 10 things you must read about VMware’s VMotion technology
VMotion is a revolutionary and powerful feature of VMware VI3 that allows for a running virtual machine to be hot migrated from one host to another without any downtime to the guest operating system. Because of the complexity of moving a virtual machine from one host to another there are some specific requirements, specifically with the host CPU that must be met for the feature to work properly. Understanding CPU compatibility can often be confusing and trying to make incompatible CPUs work together can often be challenging. Because of this VMware has recently introduced a new feature called Enhanced VMotion to help eliminate CPU compatibilities within a CPU brand. The items on this list will help you understand how the various VMotion features work, how to configure them and how to understand and overcome incompatible CPUs amongst hosts to make VMotion work. It includes blog posts from some well-known and respected bloggers that offer tips and information, important VMware knowledgebase articles that clarify the CPU compatibilities and white papers and presentations from VMware.
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1
VMware VMotion and CPU Compatibility
http://www.vmware.com/files/pdf/vmotion_info_guide.pdf
A white paper from VMware that explains how VMotion works, the differences between CPU typesand features, what CPU masks are and how to use them and what Enhanced VMotion is.
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2
Understanding CPU Compatibility Constraints for VMotion (VMworld 2007 - free registration required)
http://www.vmworld.com/mylearn?classID=11641
A VMworld 2007 presentation that explains the complexities behind CPU constraints with VMotion, problematic CPU features, compatibility groups of CPUs, relaxation of restraints and hardware support for enhanced VMotion compatibility.
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3
VMotion CPU Compatibility for Intel & AMD processors and how to override CPU masks due to CPU mismatch
http://kb.vmware.com/kb/1991 / http://kb.vmware.com/kb/1992 / http://kb.vmware.com/kb/1993
Three VMware knowledgebase articles that cover specific CPU compatibility information for Intel and AMD processors and how to override CPU masks due to CPU mismatch within CPU brands.
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4
How to obtain, configure and use VMotion and how VMotion works
http://searchvmware.techtarget.com/tip/0,289483,sid179_gci1279864,00.html
An article from Andrew Kutz that covers how to license VMotion, how to configure and use it and the technical details behind how it works.
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5
VMotion Compatibilty
http://blog.scottlowe.org/2006/11/23/vmotion-compatibility/
An article from Scott Lowe that covers CPU masks and how to understand them and set them properly to override CPU compatibility constratints.
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6
How to setup and use VMotion: A Screencast
http://searchservervirtualization.techtarget.com/generic/0,295582,sid94_gci1268244,00.html
A screencast from Andrew Kutz that show show to setup and use VMotion. It covers how to configure it, potential gotchas and how to perform a VMotion migration.
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7
What is Enhanced VMotion Compatibility anyway?
http://vmguy.com/wordpress/index.php/archives/38
An article from Dave Lawrence that explains the technical details about CPUID instructions and how Enhanced VMotion Compatibility helps to solve the problem of using incompatible CPUs with VMotion.
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8
Overview of VMotion migration compatibility error messages
http://kb.vmware.com/kb/1003684
A VMware knowledgebase article that covers the many possible error messages that may be experienced with VMotion and how to resolve them.
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9
Enhanced VMotion Compatibility (EVC) processor support
http://kb.vmware.com/kb/1003212
A VMware knowledgebase article that covers the Intel and AMD processors that are supported by Enhanced VMotion Compatibility.
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10
Live Migration with AMD-V Extended Migration Technology
http://developer.amd.com/assets/Live%20Virtual%20Machine%20Migration%20on%20AMD%20processors.pdf
A white paper from AMD that covers the challenges and technical details of using VMotion across incompatible CPUs and how CPUID instructions are used.
