In this article by Romain Serre, the author of Hyper-V 2016 Best Practices, we will learn about Why Hyper-V projects fail, Overview of the failover cluster, Storage Replica, Microsoft System Center, Migrating VMware virtual machines, and Upgrading single Hyper-v hosts.

(For more resources related to this topic, see here.)

Why Hyper-V projects fail

Before you start deploying your first production Hyper-V host, make sure that you have completed a detailed planning phase. I have been called in to many Hyper-V projects to assist in repairing what a specialist has implemented. Most of the time, I start by correcting the design because the biggest failures happen there, but are only discovered later during implementation. I remember many projects in which I was called in to assist with installations and configurations during the implementation phases, because these were the project phases where a real expert was needed.

However, based on experience, this notion is wrong. Most critical to a successful design phase are two features—its rare existence and someone with technological and organizational experience with Hyper-V. If you don't have the latter, look out for a Microsoft Partner with a Gold Competency called Management and Virtualization on Microsoft Pinpoint (http://pinpoint.microsoft.com) and take a quick look at the reviews done by customers for successful Hyper-V projects.

If you think it's expensive to hire a professional, wait until you hire an amateur. Having an expert in the design phase is the best way to accelerate your Hyper-V project.

Overview of the failover cluster

Before you start your first deployment in production, make sure you have defined the aim of the project and its smart criteria and have done a thorough analysis of the current state. After this, you should be able to plan the necessary steps to reach the target state, including a pilot phase.

instantly detected. The virtual machines running on that particular node are powered off immediately because of the hardware failure on their computing node. The remaining cluster nodes then immediately take over these VMs in an unplanned failover process and start them on their respective own hardware. The virtual machines will be the backup running after a successful boot of their operating systems and applications in just a few minutes. Hyper-V Failover Clusters work under the condition that all compute nodes have access to a shared storage instance, holding the virtual machine configuration data and its virtual hard disks. In case of a planned failover, that is, for patching compute nodes, it's possible to move running virtual machines from one cluster node to another without interrupting the VM. All cluster nodes can run virtual machines at the same time, as long as there is enough failover capacity running all services when a node goes down. Even though a Hyper-V cluster is still called a Failover Cluster, utilizing the Windows Server Failover Clustering feature, it is indeed capable of running an Active/Active Cluster.

To ensure that all these capabilities of a Failover Cluster are indeed working, it demands an accurate planning and implementation process.

Storage Replica

Storage Replica is a new feature in Windows Server 2016 that provides block replication from storage level for a data recovery plan or for a stretched cluster. Storage Replica can be used in the following scenarios:

Server-to-server storage replication using Storage Replica
Storage replication in a stretch cluster using Storage Replica
Cluster-to-cluster storage replication using Storage Replica
Server-to-itself to replicate between volumes using Storage Replica

Regarding the scenario or the bandwidth and the latency of the inter-site link, you can choose between a synchronous and an asynchronous replication. For further information about Storage Replica, you can about read this topic at http://bit.ly/2albebS.

The SMB3 protocol is used to make Storage Replica. You can leverage TCP/IP or RDMA on the network. I recommend you to implement RDMA when it is possible to reduce latency and CPU workload and to increase throughput.

Compared to Hyper-V Replica, the Storage Replica feature provides a replication of all Virtual Machines stored in a volume from the block level. Moreover, Storage Replica can replicate in the synchronous mode while Hyper-V Replica is always in the asynchronous mode. To finish, with Hyper-V Replica you have to specify the failover IP Address because the replication is executed from the VM level, whereas with Storage Replica, you don't need to specify the failover IP Address, but in case of a replication between two clusters in two different rooms, the VM networks must be configured in the destination room.

The use of Hyper-V Replica or Storage Replica depends on the disaster recovery plan you need. If you want to protect some application workloads, you can use Hyper-V Replica. On the other hand, if you have the passive room ready to restart in case of issues in the active room, Storage Replica can be a great solution because all the VMs in a volume will be already replicated.

To deploy a replication between two clusters you need two sets of storage based on iSCSI, SAS JBOD, fibre channel SAN, or Shared VHDX. For better performance I recommend you to implement SSD that will be used for the logs of Storage Replica.

Microsoft System Center

Microsoft System Center 2016 is Microsoft's solution for advanced management of Windows Server and its components, along with its dependencies such as various hardware and software products. It consists of various components that support every stage of your IT services from planning to operating over backup to automation. System Center has existed since 1994 and has evolved continuously. It now offers a great set of tools for very efficient management of server and client infrastructures. It also offers the ability to create and operate whole clouds—run in your own data center or a public cloud data center such as Microsoft Azure. Today, it's your choice whether to run your workloads on-premises or off-premises. System Center provides a standardized set of tools for a unique and consistent Cloud OS management experience.

System Center does not add any new features to Hyper-V, but it does offer great ways to make the most out of it and ensure streamlined operating processes after its implementation. System Center is licensed via the same model as Windows Server is, leveraging Standard and data center Editions on a physical host level. While every System Center component offers great value in itself, the binding of multiple components into a single workflow offers even more advantages, as shown in the following screenshot:

storage-practices-and-migration-hyper-v-2016-img-0 System Center overview

When do you need System Center? There is no right or wrong answer to this, and the most given answer by any IT consultant around the world is, "It depends".

System Center adds value to any IT environment starting with only a few systems. In my experience, a Hyper-V environment with up to three hosts, and 15 VMs can be managed efficiently without the use of System Center. If you plan to use more hosts or virtual machines, System Center will definitely be a great solution for you. Let's take a look at the components of System Center.

Migrating VMware virtual machines

If you are running virtual machines on VMware ESXi hosts, there are really good options available for moving them to Hyper-V. There are different approaches on how to convert a VMware virtual machine to Hyper-V: from the inside of the VM on a guest level, running cold conversions with the VM powered off on the host level, running hot conversions on a running VM, and so on. I will give you a short overview of the currently available tools in the market.

System Center VMM

SCVMM should not be the first tool of your choice, take a look at MVMC combined with MAT to get an equal functionality from a better working tool.

The earlier versions of SCVMM allowed online or offline conversions of VMs; the current version, 2016, allows only offline conversions of VMs. Select a powered-off VM on a VMware host or from the SCVMM library share to start the conversion. The VM conversion will convert VMware-hosted virtual machines through vCenter and ensure that the entire configuration, such as memory, virtual processor, and other machine configurations, is also migrated from the initial source. The tool also adds virtual NICs to the deployed virtual machine on Hyper-V.

The VMware tools must be uninstalled before the conversion because you won't be able to remove the VMware tools when the VM is not running on a VMware host. SCVMM 2016 supports ESXi hosts running 4.1 and 5.1 but not the latest ESX Version 5.5. SCVMM conversions are great to automate through their integrated PowerShell support and it's very easy to install upgraded Hyper-V integration services as part of the setup or by adding any kind of automation through PowerShell or System Center Orchestrator. Besides manually removing VMware tools, using SCVMM is an end-to-end solution in the migration process. You can find some PowerShell examples for SCVMM-powered V2V conversion scripts at http://bit.ly/Y4bGp8.

I don't recommend the use of this tool anymore because Microsoft doesn't spend time on this tool anymore.

Microsoft Virtual Machine Converter

Microsoft released its first version of the free solution accelerator Microsoft Virtual Machine Converter (MVMC) in 2013, and it should be available in Version 3.1 by the release of this book. MVMC provides a small and easy option to migrate selected virtual machines to Hyper-V. It takes a very similar approach to the conversion as SCVMM does. The conversion happens at a host level and offers a fully integrated end-to-end solution. MVMC supports all recent versions of VMware vSphere. It will even uninstall the VMware tools and install the Hyper-V integration services. MVMC 2.0 works with all supported Hyper-V guest operating systems, including Linux.

MVMC comes with a full GUI wizard as well as a fully scriptable command-line interface (CLI). Besides being a free tool, it is fully supported by Microsoft in case you experience any problems during the migration process. MVMC should be the first tool of your choice if you do not know which tool to use. Like most other conversion tools, it does the actual conversion on the MVMC server itself and requires its disk space to host the original VMware virtual disk as well as the converted Hyper-V disk. MVMC even offers an add-on for VMware virtual center servers to start conversions directly from the vSphere console.

The current release of MV is freely available at its official download site at http://bit.ly/1HbRIg7.

Download MVMC to the conversion system and start the click-through setup. After finishing the download, start the MVMC with the GUI by executing Mvmc.Gui.exe. The wizard guides you through some choices.

MVMC is not only capable of migrating to Hyper-V but also allows you to move virtual machines to Microsoft Azure. Follow these few steps to convert a VMware VM:

Select Hyper-V as a target.

Enter the name of the Hyper-V host you want this VM to run on and specify a fileshare to use and the format of the disks you want to create. Choosing the dynamically expanding disks should be the best option most of the time.

Enter the name of the ESXi server you want to use as a source as well as valid credentials.

Select the virtual machine to convert. Make sure it has VMware tools installed. The VM can be either powered on or off.

Enter a workspace folder to store the converted disk.

Wait for the process to finish.

There is some additional guidance available at http://bit.ly/1vBqj0U.

This is a great and easy way to migrate a single virtual machine. Repeat the steps for every other virtual machine you have, or use some automation.

Upgrading single Hyper-V hosts

If you are currently running a single host with an older version of Hyper-V and now want to upgrade this host on the same hardware, there is a limited set of decisions to be made. You want to upgrade the host with the least amount of downtime and without losing any data from your virtual machine. Before you start the upgrade process, make sure all components from your infrastructure are compatible with the new version of Hyper-V. Then it's time to prepare your hardware for this new version of Hyper-V by upgrading all firmware to the latest available version and downloading the necessary drivers for Windows Server 2016 with Hyper-V along with its installation media.

One of the most crucial questions in this update scenario is whether you should use the integrated installation option called in-place upgrade, where the existing operating system will be transformed to the recent version of Hyper-V or delete the current operating system and perform a clean installation.

While the installation experience of in-place upgrades works well when only the Hyper-V role is installed, based on experiences, some versions of upgraded systems are more likely to suffer problems. Numbers pulled from the Elanity support database show about 15 percent more support cases on upgraded systems from Windows Server 2008 R2 than clean installations. Remember how fast and easy it is nowadays to do a clean install of Hyper-V; this is why it is highly recommended to do this over upgrading existing installations. If you are currently using Windows Server 2012 R2 and want to upgrade to Windows Server 2016, note that we have not yet seen any differences in the number of support cases between the installation methods. However, clean installations of Hyper-V being so fast and easy, I barely use them.

Before starting any type of upgrade scenario, make sure you have current backups of all affected virtual machines.

Nonetheless, if you want to use the in-place upgrade, insert the Windows Server 2016 installation media and run this command from your current operating system:

Setup.exe /auto:upgrade

If it fails, it's most likely due to an incompatible application installed on the older operating system. Start the setup without the parameter to find out which applications need to be removed before executing the unattended setup.

If you upgrade from Windows Server 2012 R2, there is no additional preparation needed; if you upgrade from older operating systems, make sure to remove all snapshots from your virtual machines.

Importing virtual machines

If you choose to do a clean installation of the operating systems, you do not necessarily have to export the virtual machines first; just make sure all VMs are powered off and are stored on a different partition than your Hyper-V host OS. If you are using a SAN, disconnect all LUNs before the installation and reconnect them afterwards to ensure their integrity through the installation process. After the installation process, just reconnect the LUNs and set the disk online in diskpart or in Disk Management at Control Panel | Computer Management.

If you are using local disks, make sure not to reformat the partition with your virtual machines on it. You should export VM to another location and import them back after reformatting; more efforts are required but it is safer. Set the partition online and then reimport the virtual machines. Before you start the reimport process, make sure all dependencies of your virtual machines are available, especially vSwitches.

To import a single Hyper-V VM, use the following PowerShell cmdlet:

Import-VM -Path 'D:VMsVM01Virtual Machines2D5EECDA-8ECC-4FFC-
ACEE-66DAB72C8754.xml'

To import all virtual machines from a specific folder, use this command:

Get-ChildItem d:VMs -Recurse -Filter "Virtual Machines" | %{Get-
ChildItem $_.FullName -Filter *.xml} | %{import-vm $_.FullName -
Register}

After that, all VMs are registered and ready for use on your new Hyper-V hosts. Make sure to update the Hyper-V integration services of all virtual machines before going back into production. If you still have virtual disks in the old .vhd format, it's now time to convert them to .vhdx files. Use this PowerShell cmdlet on powered-off VMs or standalone vDisk to convert a single .vhd file:

Convert-VHD –Path d:VMstestvhd.vhd –DestinationPath 
d:VMstestvhdx.vhdx

If you want to convert the disks of all your VMs, fellow MVPs, Aidan Finn and Didier van Hoye, provided a great end-to-end solution to achieve this. This can be found at http://bit.ly/1omOagi.

I often hear from customers that they don't want to upgrade their disks, so as to be able to revert to older versions of Hyper-V when needed. First, you should know that I have never met a customer who has done that because there really is no technical reason why anyone should do this. Second, even if you would do this backwards move, running virtual machines on older Hyper-V hosts is not supported, if they had been deployed on more modern versions of Hyper-V before. The reason for this is very simple; Hyper-V does not offer a way for downgrading Hyper-V integration services. The only way to move a virtual machine back to an older Hyper-V host is by restoring a backup of the VM made earlier before the upgrade process.

Exporting virtual machines

If you want to use another physical system running a newer version of Hyper-V, you have multiple possible options. They are as follows:

When using a SAN as a shared storage, make sure all your virtual machines, including their virtual disks, are located on other LUNs rather than on the host operating system. Disconnect all LUNs hosting virtual machines from the source host and connect them to the target host. Bulk import the VMs from the specified folders.
When using SMB3 shared storage from scale-out file servers, make sure to switch access to the shared hosting VMs to the new Hyper-V hosts.
When using local hard drives and upgrading from Windows Server 2008 SP2 or Windows Server 2008 R2 with Hyper-V, it's necessary to export the virtual machines to a storage location reachable from the new host. Hyper-V servers running legacy versions of the OS (prior to 2012 R2) need to power off the VMs before an export can occur. To export a virtual machine from a host, use the following PowerShell cmdlet:
Export-VM –Name VM –Path D:
To export all virtual machines to a folder underneath the following root, use the following command:
Get-VM | Export-VM –Path D:
In most cases, it is also possible to just copy the virtual machine folders containing virtual hard disk's and configuration files to the target location and import them to Windows Server 2016 Hyper-V hosts. However, the export method is more reliable and should be preferred.
A good alternative for moving virtual machines can be the recreation of virtual machines. If you have another host up and running with a recent version of Hyper-V, it may be a good opportunity to also upgrade some guest OSes. For instance, Windows Server 2003 and 2003 R2 are out of extended support since July 2015. Depending on your applications, it may now be the right choice to create new virtual machines with Windows Server 2016 as a guest operating system and migrate your existing workloads from older VMs to these new machines.

Summary

In this article, we learned about Why Hyper-V projects fail, how to migrate VMware virtual machine and also about upgrading single Hyper-V hosts. This article also covers the overview of the failover cluster and Storage Replica.