As a geek and IT person by trade I have a somewhat unique setup at my home, in terms of computers. I have several web servers, a mail server and a large storage array that I keep running for my personal use. On the one hand, it’s fun for me and allows me to do things most people can’t dream of, but on the other hand it’s all valuable training setup and a great place to do testing before trying it on production servers at the office. The stakes are much lower for me then for the company I work for. To that end I have a stack of server hardware, sitting in my basement, running all day and night sucking down power.
As a lone person accessing the network and with several pretty low profile web sites it’s not crucial for me to have ultra high performance. All I really need is reliable hardware, and the cheaper the better. With the exception of my recent router upgrade all the hardware I use for servers are just old desktops that were replaced for one reason or another. Free hardware is (was) better then having to spend money and is a great way to get started.
These days though I’ve begun looking at not just the cost of getting the hardware, but also the cost of running it all the time. For instance, I swapped out a router that used to be running on an old desktop, to a small 6 watt embeded style device. This little box has higher specs then the tower it replaced and cost me less then $200 to put together. The old machine, when it was built was a high performance machine pulling down several hundred watts of power just to router my web traffic. The new one, in contrast, is about the size of two CD jewel cases stacked on one another and cost next to nothing to run. It was a huge step up in both performance and power savings.. and it got me thinking.
The main core of my network, as I have discussed here before, is an old machine I used to use in my recording studio. It’s a high end, or was at the time, Pentium D based system built out to handle large sessions with all the bells and whistles. It’s pulling down north of 500 watts and is tasked as a VMWare Server machine hosting all of my other servers. Plus, it’s loaded up with 4 older but hgh capacity hard drives. Without getting too technical, it sadly does not have the hardware level support for virtualization and as such seems to struggle under the load these days. I keep asking more from it and it manages, but for how long, and at what recurring cost?
The goal, going forward, is to eliminate as much power waste as possible while also giving myself a margin for failure which I currently lack. If that one machine goes down, that’s it, I’ve lost access to my storage, all my websites, and my email until I can rebuild it. In detail, I need to keep running my storage array which is attached to the computer via a full height PCI card. I need to keep three websites online and I need to keep my email server online. I want to do this on three machines, one for storage, one for web, and one for email and I want to keep the power load around 100watts total. Steep requirements…
As I began researching this project I discovered Intel’s Atom desktop boards for pretty short money. Intel’s Atom processor has been getting a lot of fanfare, in tech circles at least, as of late for their lower power consumption and reasonable speed. They are at the core of most netbooks after all. Depending on who you ask they are about as fast as a later model Pentium 4 processor and the Atom 330 model is both dual core, and hyper-threaded so it should offer me perfectly reasonable performance. The real kicker though is that the processor uses only about 8 watts of power under full load. Of course the processor of a machine is only one part of the whole package and other items will use power as well, but considering the Pentium D processor alone that I’m using now sucks down between 95 and 130 Watts, it’s a good start.
Link to: Motherboard @ Newegg.com
The next step for me was to find a case that could hold the tiny motherboard the Atom chip is attached to, offer good power efficiency and allow me to install a full size PCI card. This proved all but impossible. When Intel and most other manufactures build motherboards for these processors they make them very small. They for the most part adhere to the ‘Mini-ITX’ standard which means the board can be no larger then about 6.5″ square. This alone is Ok, but manufactures also want to build small cases to hold small motherboards. These cases almost always have fancy front panels masking the CD-Rom bay and do not support a full size PCI card. To make it worse, they often use cheap, inefficient power supplies that will draw more power then is necessary which minimizes the power savings of the processor.
Since I really wanted this machine to be a server and ideally be rack mounted I turned my sights away from the small desktop style boards to the world of rack mount computer cases. One company has announced a Mini-ITX 1U server chassis but it supports only a specific motherboard and has very few options for expansion or redundancy. They have not mentioned price or availability though so I can’t guess as to what the cost will actually be. It appears to be a modified case that they already offer, which isn’t cheap, and then you have to buy the motherboard from them as well. Not exactly the way to pinch pennies for a guy like me. The next option is to buy a more generic case and outfit it how I see fit. I have found a 4U pretty vanilla rackmount case that I am going to order and try out. It comes pretty cheap and has no power supply, which was fine by me.
Link to: 4U Rackmount Case @ Newegg I have been reading about these ‘80 Plus Certified’ power supplies and wanted to try one. I have found a 300 Watt supply for short money and am going to give that a go. To my mind this heavy duty efficient supply should be able to supply me the power I need with little wasted overhead. I could buy an ‘ITX’ power supply that can only handle 60 or 100 watts but since it’s going to be closer to capacity all the time and less efficient I think it will ultimately draw more power then the higher rated one. Just because a supply can pump out 300 watts, doesn’t mean it will do that all the time. They are built to use only what is needed. We’ll see.
Link to: 300 Watt 80 Plus Certified Power Supply @ Newegg
Aside from the RAM for the machine, which will be 2GB, the maximum the board supports, the only piece left was hard drives. This first Atom server will take over the role of file server. I already own a Norco DS-1220 and will continue to use it for the actual storage array but I don’t want to install the operating system on that array, so I need at least a couple disks in the server. Also, going forward the servers will use only local storage to host the web sites and databases so I did some real research into low power hard disks.
The new solid state drives are not in the running for me right now. They aren’t saving any real power at this point and are very expensive for pretty low capacities. I did some research into the power use of desktop style hard drives and of laptop drives. In the DS-1220 I use exclusively Western Digital Green Drives for their low power and cool running qualities but they are not a great fit for the OS on the machines. Don’t get me wrong, they could do it without a problem but they only come in sizes starting at 500GB and use about 3 watts at idle and about 6 watts when in use. That’s really great for large capacity storage when compared with standard drives that idle at nearly 8 watts but I don’t need nearly that much storage, I only need a few gigabytes per server.
I turned to Fujitsu’s higher performing laptop drives. These disks spin at the same speed as desktop class drives and are nearly as fast but idle at less then 1 watt and use slightly more then 2 watts under load. Perfect. I can get an 80GB disk for $40 but since it’s a server I’ll get two and run them in a RAID 1.
Link to: 80GB 7200RPM Hitachi 2.5″ SATA Drive
I then had to sort out how to mount such small drives in such a large case. What I discovered is a small device that will allow you to mount 4 of these drives in the space of a CD-Rom drive bay. For this first server, I only want two disks, so the device will only be half full. In future servers that will host websites and databases I may want to use all four slots. Since the motherboard only has two SATA ports I’ll need to add a PCI SATA card but since I have the full size PCI slots in the case, that’s not a problem. See, planning does pay off!
Link to: Athena Power 2.5″ SATA Backplane Unit @ Newegg.com With a total cost of about $400 shipped I can setup two of these machines for well less then $1000 and still have huge power savings. I’m going to order the parts for the first one in the coming weeks and will do some testing to determine how much power is used and if I can or should try to make more cuts. I’m going to pickup a ‘Kill-a-Watt’ to help with that.
You’ll notice I didn’t add a CD-Rom drive to the setup. If I decide I actually want one, I’ll use one of the spare drives I have kicking around. Odds are I will use it for installation and then never again, so I’ll probably just use a USB one for that. No reason to leave it plugged in and on all the time if I’m not going to use it.
So far, I see only two problems with the setup. The first one is that these machines won’t be able to handle much if any real virtualization load. I plan to work around that by making better use of the software available to me. Right now each web site has it’s own unique virtual machine sucking up more resources then it really has to. I should be able to consolidate all my web sites onto one machine with Apache virtual hosts. Fingers crossed..
The other possible issue is the rack mount case I have chosen is not specifically a Mini-ITX case so there is a chance it won’t have the screw holes I need to mount the motherboard to it. From the pictures it looks like it has way more screw holes then any computer case I’ve ever seen so I’m hoping they have planned for all kinds of systems. If not, it’s a simple matter to drill out a couple more holes. These machines aren’t going to get bumped around so they don’t need to be super hardy anyway.
Check back for more info!
Topslakr
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