VMware vSphere 6.0 Part 6 - P2V Migrations With Converter

VMware vCenter Converter is a general purpose VM conversion tool that makes it easy to cope with diverse VM and image formats. Converter's job is to facilitate the migration of physical and/or virtual machines from one host to another.

When in doubt, simply boot the source machine and point Converter at it. When in doubt, tell Converter that the source is simply a Powered on machine.

Source for supported source machine images - VMware vCenter Converter 6 release notes.

Note: Not all features supported on all operating systems. Please see the Converter Standalone User's Guide on VMware's web site. Also check the product release notes:

officially supported but may still work.

The key task completed by VMware vCenter Converter is the cloning of a source disk to a virtual disk. This can be performed either hot (while the source machine is running) or cold. Of the two, Cold cloning is more trustworthy (because the source disk isn't being changed while it is being cloned) but involves down time.

The result of cloning source disk(s) is a corresponding virtual disk on a datastore. Once the disk has been cloned, VMware vCenter Converter will build a VM around the virtual disk to match the hardware characteristics of the source machine.

Because the new virtual disk is a clone of the source machine's disk, there is a risk that booting the VM will cause an identity conflict with the source machine. While this isn't an issue if you have powered down the source machine, it is a concern if you are simply doing test migrations (to validate procedures, etc.) in preparation for a real migration. In this case, you can either:

• Boot the new VM on a completely isolated virtual network to avoid any risk of identity clash, or
• Use Guest OS Customization to assign a new identity to the new VM

VMware vCenter Converter goes through four steps to hot migrate a source machine to a virtual machine. While these are discrete steps, they are not executed sequentially – so you may find VMware vCenter Converter creating the new target VM while the source disk is still being copied.

VMware vCenter Converter needs administrative level credentials for the source machine. You can supply the local machine Administrator password or you can use any other credentials that would grant Converter full administrator rights to the system.

VMware vCenter Converter can P2V an active system... and will snapshot the system to quiesce local drives before copying the local volumes to new virtual disks. There are a couple of things to keep in mind during this process:

Quiet machines make for better conversions. If you can quiesce the local machine, then there is a much higher chance that the converted disks and the data they hold will be complete and usable. A simple way to do this is to wait for a maintenance window, shut down all applications, disable all unneeded services and then do the hot conversion.

There must be sufficient room on the local volumes for VMware vCenter Converter to create snapshot files. Converter needs space to accumulate pending disk updates (and snapshot files are used for this purpose). If you do not have sufficient space, then the conversion process will either fail to start or will fail when the local volume fills up. You should have a minimum of 500MB to 1GB of free space before attempting a conversion on an active machine.

You begin the P2V process by launching the Converter client:

Start > All Programs > VMware > VMware vCenter Converter Standalone Client

Before beginning a conversion, you should:

• Get administrator level credentials on the source machine
• Audit the source machine to ensure it is a good candidate for conversion
• Verify that the source machine has room for a snapshot file for each disk

Next, select Import Machine... which launches the Import Machine Wizard.

Converter starts by extracting a profile of your machine including:

• Number of CPU cores
• Provisioned RAM
• Number of NICs
• Number of NTFS volumes

Converter uses this information to build a comparable virtual machine. As we will see later, right-sizing your new VM after conversion is an important step – that helps ensure your VM isn't over provisioned.

This step lets you set detailed properties for your target VM, including:

• VM destination name and the folder it will live in
• Target disk properties including their new size and type (thin or thick)
• CPU count and memory size
• The number of virtual NICs in the target VM and the port group used
• Services running on the source VM that you may wish to disable on the Target VM (such as server health monitoring agents)
• Advanced options such as; post copy disk synchronization, guest OS Customization, etc.

The result is that you have full control over the conversion process!

Note: you must click the Edit link beside each property to change their values

A lack of free space on the disk being converted can prevent you from doing hot conversions...

VMware vCenter Converter uses Microsoft Volume Shadow Copy Services (VSS) to quiesce the local disk. VSS needs between 500MB and 2+GB of free space on the disk being converted to hold snapshot files, converter agents, etc. If this space is not available, then Converter may not be able to hot convert your virtual machine.

If you encounter this problem, you should try to free up disk space and try again. You may be able to free up enough disk space to allow Converter to proceed. A great tool for freeing up disk space is CCleaner which is available for free. CCLeaner cleans up Windows patches, old temporary files, stale download files, browser cache files, etc.

To resize the target disk:

• Click Edit beside Data to copy
• To skip a disk, uncheck it from the disk roster
• To change the target disk size (up or down), click the Destination Size field
• To change the target disk datastore, click the Destination Datastore field

If your virtual disk size matches the source disk size, then Converter will perform a simple block by block copy of the source volume to the virtual disk. Depending on the size of the source volume, this copy could take a number of hours.

If the virtual disk size is different from the source disk size, the Converter will:

• Make the new virtual disk of the declared size
• Partition and format the virtual disk according to best practices for the target OS
• Align all partitions correctly for efficient storage access
• Copy all files/directories from the source volume to the virtual disk

File copies are used because that is the only way Converter can get the contents of the source volume to the new virtual disk. There are advantages and disadvantages to this approach

• Files are copied sequentially so the target disk is defragmented- The copy is faster because only disk blocks owned by files and directories are copied
• The target disk size does not need to match the source volume
• Overall copy speed for volume based cloning will be slower than for disk based cloning

As part of the P2V process VMware vCenter Converter will make a new VM on your designated ESXi host. VMware vCenter Converter tries to match the new VM's virtual hardware to the hardware profile of the machine being converted. As a result, unless you override the default settings, your new VM will have the same

• Number of vCPU cores as pCPU cores
• Memory size
• Number of NICs (up to 10)
• Number of virtual disks (subject to review and change)
• USB ports

It is important that you review the hardware configuration of your VM once the conversion process is completed. Over provisioning of physical hardware is one habit we do not want to carry over to our virtual world.

VMware vCenter Converter will download, install and use Windows agents to synchronize and snapshot local source volumes. These agents are activated once VMware vCenter Converter is told which disks will be converted (to virtual disks) and which disks will be left behind.

VMware vCenter Converter needs to update the operating system files on the newly converted OS disk. VMware vCenter Converter must:

• Update the OS HAL and Registry of the virtual disk so that the OS is correctly configured to use VM virtual hardware
• Install Guest OS drivers for VMware virtual hardware
• Remove references to source machine drivers configured into the OS
• Add VMware Tools to the Guest OS
• etc.

These changes are made so that, when the VM first boots and performs a virtual hardware scan, it can recognize and use virtual devices. You should also be careful to remove any hardware specific health monitoring agents from the VM. Tools like HP's Insight Manager, Dell's Open Manage, or IBM's Director agents will complain bitterly when the hardware they were designed to monitor no longer exists (because the hardware is now virtual).

If this is a test conversion, you may also wish to perform Guest OS Customizations to assign a new identity to the converted VM. In this way, your new VM will not identity clash (duplicate license, IP, FQDN, etc.) with the source machine.

Once conversion has completed, vCenter will connect to the source machine one last time to remove the agents used during the conversion process. That way, there is no risk of residual Converter agents causing problems if the source machine is kept in service.

Before Converter agents are removed, VMware vCenter Converter will commit any snapshots on source disks. Once the commit has completed, VMware vCenter Converter will delete the associated snapshot files.

Perform a quick audit on the newly created VM. Review and adjust the virtual hardware as needed:

• Check to see that you have a CD/DVD Drive 1 device. If not, add it
• Check to see that you have a floppy 1 device. If not (and you need one) add it
• Adjust the VM's RAM allocation up/down to suit the workloads RAM needs
• Adjust the CPU count up/down to suit the VM's actual CPU needs; and to adjust for the speed differences between the old source machine and the ESXi host CPU speed
• Remove any virtual COM and LPT ports present (unless you need them)
• Etc.

Once the VM boots, log in and check Device Manager. Remove references to no-longer present devices. Correct any hardware warnings you see.

Run Control Panel > Add/Remove Programs.

Check for server monitoring agents and remove any you find

Review Windows Services. Did all services start?

When selecting source machines for conversion, review the machine and applications looking for configurations that would prevent Converter from doing it's job, including:

• Hardware of a category that is not available with virtual hardware. Examples would include Voice cards, Fax modems, etc.
• Workloads that require more hardware resources than a VM can deliver. Examples would be workloads that need more than 8/32/64 cores of CPU cycles, more than 1TB of RAM, etc.
• Applications that require high end 3D accelerated graphics. It is possible to install a 3D hardware accelerated graphics card into an ESXi host and share it's display memory with VMs. To do this, you must: be using Windows 7 or Windows 8 VMs, (not Windows Server), must have a supported nVidia Quadro or AMD FireGL card, and be running the VM in a VMware View 5.2 or higher environment
• Applications that are keyed to the source hardware (such as NIC MAC address, disk geometry, motherboard UUID), etc. You can copy the MAC address of the NIC in your source machine into your VM NIC (just Edit the VM's settings, select NIC1 and edit it's MAC address to match the source NIC MAC address)

USB devices can be carried over. To do this:

• Add a USB controller to your VM
• Plug the USB dongle into your ESXi host
• Configure a USB device at your VM and map it to the physical USB port on your ESXi host

There are a couple of things that can slow down or stop a Converter P2V migration. You must open up the source machine's firewall sufficiently so that Converter can access the host on ports 137, 138, 139, 443, 445 and 902. You must not have software mirroring configured for the Windows boot volume (if you do, break the mirror, convert and then re-establish the mirror).

Converter works on most popular Windows releases and Linux, but not Solaris, BSD or NetWare, etc. If you need to P2V unsupported workloads, download VMware's stand alone Converter product or PlateSpin's Migrate product.

VMware vCenter Converter can migrate source Windows 2003/2008/2012, Vista and Windows 7, 8 machines without the need to reboot. This is because the Windows 2003 kernel can dynamically load and unload kernel level drivers. Windows XP lacks this feature so you must reboot these operating systems after the snapshot agents are installed and also after the conversion has completed (to remove the Converter agents from Windows).

VMware best practices Knowledge Base article for vSphere Converter is KB1004588

The P2V Admin ISO image is a great collection of tools that could come in very handy. It includes a number of tools (all free/open source) including:

• Disk defragmentation tools
• Partition alignment tools
• Guest OS drivers for virtual hardware
• Disk cloning tools
• File copy tools
• Sysprep files for W2k, Windows XP, W2k3 (all versions)
• Many additional utilities.

A quick web search should help you find where you can download the P2V Admin ISO.