Virtualized data centre–Part three: Architecture
- by marc dekeyser
Having the basics (like discussed in the previous articles) is all good and well, but how do we get started on this?! It can be quite daunting after all! From my own point of view I can absolutely confirm your worries and concerns, but also tell you that it is not as hard as it seems! Deciding on what kind of motherboard to buy, processor and how much memory is an activity you will spend quite some time doing research on. And that is not even mentioning storage! All in all it comes down to setting you expectations and your budget. Probably adjusting your expectations according to your budget :). Processors As a rule of thumb you want VT-D (virtualization) technology built in to the processor allowing you to have 64 bit machines running on your host. Memory The more the better! If you are building a home lab don’t bother with ECC unless you are going to run machines that absolutely should be on all the time and your comfort depends on it! Motherboard Depends on what you are going to do with storage: If you are going the NAS way then the number of SATA port/RAID capabilities do not really matter. If you decide to have a single server with lots of dedicated storage it obviously matters how much SATA ports you will have, alternatively you could use a RAID controller (but these set you back a pretty penny if you want one. DELL 6i’s are usually available for a good bargain if you can find one!). Easiest is to get one with a built-in graphics card (on-board) as you are just adding more heat, power usage and possible points of failure. Networking Just like your choice of motherboard the networking side tends to depend on how you want to go. A single virtualization host with local storage can usually get away with having a single network card, a cluster or server which uses iSCSI storage tends to have more than one teamed up :). Storage The dreaded beast from the dark! The horror which lives in the forest! The most difficult decision you are going to make in the building of your lab. Why you might ask? Simple my friend, having the right choice of storage can make or break your virtualization solution. The performance of you storage choice will have an important impact on the responsiveness of your virtual machines and the deployment of new machines. It also makes a run with your budget! If you decide to go the NAS route you will be dropping a lot more money than if you would be having just a bunch of disks sitting in a server and manually distributing the virtual machines over the disks. Platform I’m a Microsoftee so Hyper-V is a dead giveaway for me. If you are interested in using VMware I won’t stop you but the rest of my posts will be oriented on Server 2012 Hyper-V (aka 3.0)! What did I use? Before someone asks me this in the comments I’ll give you a quick run down of what I am using. - Intel 2.4 quad core processors (i something something) - 24 GB DDR3 Memory - Single disk in each server (might look at this as I move the servers to 2012) - Synology DS1812+ NAS - 3 network interfaces where possible - HP1800 procurve managed switch I decided to spring for the NAS as I will also be using it for backups and media storage (which is working out quite nicely with my Xbox 360 I must say). At the time of building my 2 boxes (over a year and a half ago) these set me back about 900 euros each so I can image you can build the same or better for a lower price. Next article will be diagramming what I want to achieve and starting a build on the Hyper V 3.0 cluster!