This is my third article on building a lab to study for VCP5, the first was about using a computer you also use for other things and hosted virtualisation, the second was about retired servers. This one is about dedicating a PC running ESXi.
A desktop class computer will run quieter and consume less power than a server. It is also easier to buy quiet and low power components to make your white box even less intrusive, compared to servers. If you can dedicate a PC to being an ESXi host then it can stay on most (all) of the time, saving you the start-up and shutdown time that is inherent in non-dedicated use. The dedicated PC will also likely be a desktop, this usually means a faster CPU, more DIMM slots and larger hard disk than a laptop of the same price.
While they are not on the HCL ESXi supports desktop class motherboards. With ESXi v5.0 even some low end NICs will work, including the RealTech one on my motherboard. As time has passed it has become much more practical to run ESXi on inexpensive hardware. There are a number of web sites with ESXi 4.0 compatibility lists. I haven’t yet found a good V5 list, although V5.0 seems to support everything 4.1 supported and some more.
Since ESXi can be run in a VM on ESXi you can do all of your training and testing using nested ESXi, while also running other VMs to provide services to the network, like a NAS VM, mail server or other roles.
This is how my lab ran for two years. My whitebox lab was a Asus i7 Motherboard with triple channel memory. This means six DIMM slots, so with 4GB DIMMs that was 24GB, unfortunately triple channel memory seems to be a thing of the past. Enough to run a full SBS, vCentre and a full View implementation as well as a few utility VMs. I have an Intel RAID adapter with six 1.5TB SATA disks in RAID10, so I got reasonable disk performance and redundancy. In addition I installed two Intel desktop class NICs as the RealTech wasn’t supported with ESXi 4, teh Intels will also perform better.
The limitation on desktop class motherboards tends to be DIMM slots and supported DIMM size. Few motherboards have more than 4 DIMM slots or support 8GB DIMMs, so usually 16GB is the maximum. I have only moved to the blade servers so I could put more RAM in and run SRM or VSA nested to learn about them.
Installing ESXi on a dedicated desktop allows more VMs to be run than using hosted virtualisation (Workstation or Player) on a dedicated PC. If you don’t have access to vSphere licensing the host could run the free edition of ESXi, called the vSphere hypervisor. The free edition uses exactly the same software as the licensed ESXi, it simply has restrictive licensing.
On the other hand using ESXi means that the PC is dedicated to being the lab server, it can’t also be used to play games or as a media centre PC. To use the PC for other things as well take a look at my post about hosted virtualisation.
© 2011, Alastair. All rights reserved.