Virtualization

Until recently, most of the servers in my setup hosted single functions, such as Domain Services, DFS or single applications. I decided that I wanted to see if virtualization offered any advantages for my home setup, so I am now on a journey to explore its use in my home environment.

There are far better resources on the web (Google is your friend!) that cover the subject of virtualization than my pages here, but I have made a few notes, mainly as a learning exercise for me, that others may find useful, so FWIW, here you go . . .

Hypervisors are broadly defined as two types :-

• Type 1, where the hypervisor runs directly on the system hardware - so called, "bare-metal" hypervisors, and
• Type 2, where the hypervisor runs on a host operating system that provides hypervisor services

Recent versions of Windows Server have a Hyper-V Type 1 hypervisor edition as well as a Type 2 hypervisor that can be installed as a server role. Microsoft makes the Hyper-V Server available for FREE! The Windows 2012R2 Hyper-V was available for download until March 2020, when it was retired. Since then, versions of Hyper-V Server built on Windows Server 2016 and 2019 continue to be available. Given the age of my hardware, the 2012R2 version seemed to be the most appropriate for me to try.

The decision on whether to use a Windows Type 1 or a Type 2 hypervisor is influenced by a number of factors, including :-

• Cost - the Type 1 hypervisor is available for free (though the guest OS(s) do need to be licensed)
• Security - the Type 1 hypervisor resembles Server Core, it does not have a GUI and is less susceptible to attack

Another consideration is around hardware configuration and monitoring of the physical server hardware. HP ProLiant servers have a large suite of hardware configuration and monitoring programs available, these must be installed on the base server and are much easier to use when the full version of the server, with GUI, is being used. (more details here)

Windows Hyper-V

For my first foray into the world of virtualization, I chose to use the Type 1 hypervisor, installed on ProLiant DL360 G5 hardware.

After some initial success, it became clear that the resources available on the hardware that I was using was going to severely limit the number of virtual machines that I could run when installing the most recent server operating systems such as Windows Server 2016 and 2019 and a hardware upgrade was going to be needed. 

VMware ESXi

I managed to pick up a couple of more powerful, but still quite old, ProLiant Generation 7 servers for a very good price that were intended to help me migrate to more capable hardware. The only problem with these servers was their limited number of drive bays. They were the 4 bay version and not easily upgradeable to 8 so I was worried about the lack of affordable disk space. However, the servers had internal USB and SD card slots in which a full version of VMware's ESXi type 1 hypervisor could be installed, allowing all of the hard disk bays to be used for Virtual Machine data stores.

When I bought the servers, the seller also supplied a copy of the HP custom build of ESXi for the machines. ESXi can also be installed for free, and this persuaded me to try out VMware. When ESXi is first installed, the full suite of features are enabled for 60 days in "evaluation" mode, if the software is not licensed after that time, if reverts to the free version which only allows a very limited subset of the features to work, but the hypervisor and guest OSs continue to function.