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Highly available virtual machines are one of several possible roles in a failover cluster. The preferred tool for managing them is still the failover cluster manager (FCM). For the management of VMs, it resembles the user interface of Hyper-V Manager, so that admins largely find the same dialog boxes there.
Like the other RSAT tools, the FCM has not received any significant update for quite some time. If you start the FCM under Windows 10, you will see a message that recommends Windows Admin Center (WAC) over the FCM.
Microsoft promotes the WAC as an alternative to the FCM but cannot completely replace the RSAT tool
In fact, a number of innovations, such as for the management of Azure Stack HCI or the software-defined networking of Hyper-V, exclusively benefit the WAC. At the same time, however, it still lacks some basic functions, for which one must fall back on other tools.
Prerequisites for creating a VM
Thanks to the Cluster Creation Tool, a Hyper-V cluster can be set up completely in WAC. The starting point is a few computers with a freshly installed Windows Server. The tool then takes over the entire workflow, including domain join, installation of updates and server roles, setting up the virtual network, and shaping the cluster.
In a conventional Hyper-V cluster, the virtual disks are usually stored on a shared storage, which is typically connected via iSCSI or FC. WAC lacks essential functions here because you cannot activate and configure the iSCSI initiator on the nodes with it.
Therefore, this task must be done the conventional way, i.e., using iscsicpl.exe or PowerShell. The former also works on Server Core if you connect to the nodes via RDP.
Separate tools must be used to configure the iSCSI initiator
The next step is to convert the assigned LUN into a Cluster Shared Volume (CSV). Here, too, the WAC lacks the respective function, so that one is dependent on the conventional means.
Create a highly available VM
Highly available VMs, which restart on another host if a node fails, are a cluster feature. Therefore, you create them via the WAC Cluster Manager as soon as all requirements are met.
There, you will find the Roles entry in the navigation. You can add new roles via the corresponding page. Unlike in FCM, however, you do not get a selection of available roles; you can only enter a name for a quasi-empty role.
Highly available VMs created via Virtual Machines subsequently appear under Roles
Instead, you create a VM via Add > New under Virtual machines, which then appears later in the overview for the roles. The dialog for the new VM contains the most important settings, such as name, path for saving the configuration, the number of processors, or the size of the RAM.
Problems when creating a VHD
To attach a VHDX to the virtual machine, click on + Add under Storage. If you want to create a new virtual disk, you can only select its size; the name will be generated automatically. But the Create button might remain disabled.
Disabled buttons prevent the configuration of the VM storage
In this case, you have to switch to the FCM to create a VHD(X). When using a CSV, the link to the shared storage is found by default under C:\ClusterStorage.
Create a new virtual drive for the VM in the FCM
In my lab, VHDs stored there did not appear in the VM overview of the WAC; they are considered unavailable.
Assign installation media
The disabled Create button also affects the selection of the ISO from which the operating system is to be installed, because it applies to the entire storage section. In addition, the Browse dialog box sometimes does not show the file system of the host selected in the settings above.
In this situation, as well, you have to resort to FCM or PowerShell. Generally, the limitation that generation 2 VMs cannot access physical DVD drives also applies there, and an ISO file for a virtual DVD must be located on the local storage of the host.
Once you have overcome these hurdles and created the VM, you can start installing the guest OS. To do this, you should first check the boot order in the VM settings to see if the DVD drive configured as the first boot device.
Start the VM and establish a connection
In the Hyper-V Manager, you first establish a connection to the virtual machine via VM Connect, then start it from there, and finally confirm booting from DVD by pressing a button. This procedure, however, does not work with the browser-based WAC.
A connection to the VM can only be established when it is switched on
Here, you start the VM first via the Power menu and only then can you connect to it via Remote Desktop. By the time you have logged in, it is usually too late to select the boot medium. Therefore, restart the VM via the menu item Send Ctrl + Alt + Del and then go through the OS setup.
To get to the setup you may have to restart the VM via Send Ctrl+Alt+Del
Conclusion
With the Cluster Creation Tool, the Admin Center masters the entire workflow for setting up a cluster, and it only requires a standard installation of Windows Server on the individual nodes. But the browser tools are still missing some essential functions for the complete management of a cluster; hence, admins still have to switch to the FCM or PowerShell.
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In addition to the functional gaps, the Admin Center suffers from notorious quality problems. Hardly any complex task can be completed without being confronted with one of the numerous bugs or unexpected errors. The convenience of browser-based management also comes at the price of slow performance.
