My job now involves more and more virtualised (or virtualized if you’re one of our American cousins from across the pond) server implementations so this is a good excuse to go and build my own VMware ESX test environment.
As most of you probably know much of issues faced by those wanting to build their own cheap ESX test server is having SCSI disk on which to present the Virtual Machine File System (VMFS).
There are a handful, and more with ESX v3.5, of SATA disk controllers that present the disks to ESX as being SCSI. Obviously due to the cost of SATA Vs SCSI/SAS disks this is preferable for a low cost ESX box.
I was wanting a server that would offer half decent performance and wasn’t going to cost the earth. Probably the cheapest, and one of the most hassle free ways would be to purchase an HP Compaq D530 desktop. vinf.net has blogged quite extensively here and here about his experiences with running ESX on the D530. A basic model can be picked up on EBay from about £80 (with minimum memory and disk) though it would be worth hunting around for a version with the 2.8Ghz Hyper Threaded (HT) CPU which will offer more in the way of performance.
The D530 is an attractive little unit on many fronts though I was a little concerned about the performance as ESX and it’s VM’s would be running off of a single hard drive. Although this would be fine for any low/moderate resource intensive VM’s I was hoping for something which would give me that added flexibility of a little more horse-power under the hood, especially in the area of disk access speeds.
I have an existing homemade desktop machine which has an AMD X2 4200 CPU, 4GB memory and onboard RAID 0 SATA II 320GB hard disks which runs very well. All I would have to have added to this PC is an ESX compatible SATA controller such as the LSI MegaRaid 150 and a compatible network adapter. The LSI MegaRaid 150 is a 64bit PCI adapter and as such I would have lost valuable bandwidth as my ABit motherboard only had 32bit PCI slots available. So to get the most out of the disk controller I would have had to have purchased a new motherboard and in using my existing PC as a dedicated ESX test rig I would be down one PC that I use for all my day to day computing bits and pieces.
After much more trawling of VM forums regarding ESX white boxes I decided to take the plunge and go for an entry level HP server with an entry level ESX certified disk controller.
As budget is an issue the HP Proliant ML110 (Intel) or HP ML115 (AMD) seemed like an obvious choice. I have worked with HP Proliants for a number of years now and have always been impressed with their build quality and reliability even on low end models.
Both the ML110 and ML115 have onboard SATA raid though there wasn’t any clear definitive information on whether the controller would allow the SATA disks to be seen as SCSI based by ESX – as is necessary for the VMFS volume. This wasn’t to be an issue however as I had also decided to buy and install an HP Smart Array e200i Controller. This controller can control both SATA and SAS drives so offered some future proofing for when SAS drives become more affordable and mainstream in the home market. Unfortunately the e200i only offers SATA I (1.5Gb/s) speeds though hopefully by using 2 disks in a RAID 0 (Ok, I know where’s the redundancy? – but keep in mind that this is only a test rig) configuration I should get decent enough performance in the disk access department. An HP specific 4 port SATA cable is also needed (HP PN: 430762-001).
UPDATE: I have posted another article that outlines things to look out for when going to buy an HP Proliant ML110 G4 to run ESX. Click here for more details.
The cost of a new ML110 (G4 or G5) was inexpensive enough to make it not worth the time trying to hunt for a bargain on EBay or the like. The cheapest (UK based) online vendor I found to buy an ML110 was ‘Servers Direct’. They, apparently have bought up all of HP’s remaining ML110 G4 models (G5 is the latest) from HP so are now selling them off at a reduced price (ie: £149.00). *UPDATE: Check out the TechHead ‘Hot Deals’ page for the best up to date pricing I can find for the ML110 or ML115’s.
Here is an overview of the HP ML110 G4 specification:
I have never used, or bought, an ML110 before and am used to using it’s more SMB and Enterprise level Proliant cousins such as the Proilant DL380, etc.
The first thing that struck me was it’s size… it’s really small. Smaller in fact than my current PC’s midi-tower case. This is good news as I have limited space in my inner-city London flat.
I set about installing 2 Samsung SpinPoint 320GB hard disks – to be used in a RAID 0 configuration off of the e200i controller.
My plan with the hard disks is to run ESX off of the SATA hard disk that came with the server (160GB) which runs off of the motherboards SATA controller and then create the VMFS volumes on the raided 320GB drives which are connected to the e200i.
The HP Smart Array e200i comes with 128MB of Battery Backed Write Cache.
Here is the necessary HP SAS/SATA cable that connects the hard disks to the e200i array controller.
Unfortunately standard SATA cables won’t work. It costs £14 and the HP part number is 430762. Most of the suppliers I contacted always seemed to be out of stock.
Once I had added the memory it was time to start it up and install ESX v3.5!
Another item of note with the ML110 is how quiet it is. It is perfectly quiet enough to have this server running in a room without really knowing it’s actually switched on. I wouldn’t say it’s completely silent but it is no louder than your average PC.
Installing VMware ESX v3.5 was straight forward. It picked up all the hardware devices first time (ie: disk controllers, NIC, etc).
Before I knew it I had a working ESX installation which I could connect to via the VMware Infrastructure Manager which is running on my PC.
One interesting point of note is that ESX see’s the hard disk connected to the onboard SATA controller as a SCSI VMFS3 device so I could have saved some money and run my ESX install and the VM images off of the onboard SATA controller.
I have created a VM instance on the disk connected to the onboard controller and can confirm it works just fine. Though, as with the D530 if you want to spin up a number of VM instances depending on what these instances are doing (ie: a task that involves moderate or high disk IO) I could foresee disk access being a potential bottle neck and a separate disk controller preferable. That said, as this is just a ESX test server then in most cases the VM instances will most likely not be doing anything too resource intensive.
So all up this is what creating my VMware ESX v3.5 test server cost:
1 x HP ML110 G4 £149.00 (www.serversplus.com)
1 x HP e200i Array Controller £173.00 (www.serversplus.com)
1 x HP SATA/SATA Cable £14.00 (www.serversplus.com)
4 x Corsair 1GB XMS2 Mem £80.00 (www.overclockers.co.uk)
2 x Samsung 320GB Hard Disk £104.00 (www.overclockers.co.uk)
I hope this has helped you if you’re currently looking around for a low cost ESX test server. Please leave any comments or questions.
UPDATE: Check out my blog article here on installing VMware ESX 3i 3.5 on an ML110 G5.
UPDATE: I have had a number of queries regarding the NIC and the onboard disk controller running with ESX. I am currently creating an article that outlines what revisions (eg: G4, G5) of the ML110 and ML115 are fully compatible with ESX (v3.5) and those that aren’t or where there are tweaks or a work around. Here is a link to my temporary blog posting – whilst I compile this information. Check back soon or add me to your RSS feed to be notified when I finish the final article.