Archive

Monthly Archives: January 2013

Lets talk about the motherboard. As I wrote in the previous post I was looking for the smallest possible board. That’s the Mini ITX size. I wanted to put the latest Intel CPU on it, that means LGA 1155 socket. I wanted the server to use ECC memory. There are a lot of discussions on the Web talking ECC up and down. After reading some boards and some papers, I came to the conclusion that if I have the box to handle a huge amount of data, I’d rather make sure a chance of it getting corrupted in memory is minimized. Finally, I wanted to get some decent graphics support from the Intel CPU itself, that means C206 chipset. I could find only two motherboards that satisfy these requirements: WADE-8011 from Portwell and S1200KP from Intel. The latter was widely available and relatively cheap comparing to the former one, so the decision was simple: I ordered the Intel board. Please note that S1200KP does not support Ivy Bridge CPUs. Intel has an updated version S1200KPR out that supports both Sandy and Ivy Bridge.

The choice of the CPU was pretty straightforward as well — I went with the cheapest Xeon CPU that supported graphics and 8 threads: e3-1235. In retrospect, I could have used a less power hungry CPU, e.g., i3-2125. I thought that 30W tradeoff was worth additional speed and performance. I might have been wrong, but boy! Does this thing fly!

One thing that surprised me while I was building the server is how small was the selection of possible components. Living in the Mac Universe and listening to stories about how much variety and choices the PC side has, I sort of assumed that if you are to build a computer from parts, there will many different models to choose from. Not exactly true…

Lets start with the case. As I said I want the server to be as small as possible. That comes down to a Mini ITX motherboard and the corresponding case. Lets find a case designed for a Mini ITX board that can hold 6 hard drives, one optical drive, and one SSD drive. After searching high and low I found only two cases that satisfy these requirements: Lian Li PC-Q08 and Lian Li PC-Q18.

Lin Li PC-Q08A

Lian Li PC-Q18A

If you know of any other cases that meet the above requirements, please drop me a note in the comment section.

The former case is about two years old, the latter showed up in the stores right when I was building the server. After looking at the specs I picked PC-Q08 for two simple reasons: It has space for a 110mm CPU cooler (PC-18Q can only accommodate 80mm cooler) and it does not have the ugly Lian Li label in front of the box. And, it was about $50 cheaper at that time. There are some aspects where the newer case is better: it has 140mm fan on top of the case (instead of 120mm); it has a dedicated motherboard tray inside (the former case mounts the motherboard on a side panel). There is some space behind the tray for better cable management. It also has a bit more space for a PSU (160mm vs 140mm). Four of the drives are mounted on a “real” SATA backplane, making installation and management of the drives easier. I read that the overall construction is more solid resulting in significant vibration reduction. However, the cooler height was a very important factor for me and I will talk about it in one of the next posts.

I finally got a bit of time to write about the new server I built last year. It has been up and running since May 2012. It runs Mountain Lion Server with Open Directory allowing me to manage multiple users and devices on my home network; stores and shares my media collection; handles Time Machine backups; and serves as a web server for some of my small projects.

The Microserver is now serves as an offsite backup unit storing nightly zfs snapshots of the data. It seems to work fine for this purpose.

Lets start with listing the requirements I had for the server box. Here they are in no particular order.

  1. Capacity. I want the server to maintain a huge data storage pool. The box has to hold a lot of hard drives. How many hard drives should I plan for? That sort of comes down to the next topic…
  2. Reliability. I want the storage to be very reliable to possible hard drive failures. If I use zfs for storage, I can dedicate some drives for the actual data and some for redundant information that can recover files in case of drive failure. (It does not work exactly like this, but it’s OK for the analysis.) I estimated that I need space for 6 drives: 4 to old the data and 2 for redundancy. If I go with 2TB drives, it gives me 8TB storage. If I use 3TB drives, it comes to 12TB storage, which should serve me well for quite a while.
  3. Blu-ray. I need a space for a Blu-ray drive to watch movies and write and occasional disk.
  4. Finally, I need space for a system drive, because it’s very likely I would not be able to boot from a ZFS drive.
  5. The box has to be small. I have a Mac Pro at home and I do not need another box of similar size sitting around.
  6. It has to be quiet. The box will be sitting in a living room and I do not want to hear it.
  7. I want the box to run MacOS X. I can configure a Linux box, but it would take me too much time and effort that I do not want to expend.
  8. It has to be powerful enough to run some computational tasks, like indexing and searching of document collections.
  9. It’s a server, so it does not need support for a very good graphics card. At the same I want to be able to plugin a DVI monitor occasionally.

Why did I want to replace the Microserver? With 6 drives mounted inside, it has no space for an optical drive (fail on #3). It uses a very power efficient CPU, which is fine for a file server, but insufficient for any other tasks (fail on #8). It uses AMD CPU. OSX for AMD is getting less and less support from the hackintosh community and AMD compatibility with the current OSX versions is falling behind. For example, OSX kernel runs in 32 bit mode on an AMD CPU. The latest ZEVO requires 64 bit kernel. So, I cannot update my ZFS setup on the Microserver beyond the ZEVO Developer Edition beta from last summer.

So, why did I not go with a Mac Pro? Because of three reasons: Mac Pro is huge (#5), there is not enough space for 6 hard drives in a Mac Pro (#1), and it’s expensive. Very expensive. Finally, while researching the information about the Microserver, I got drawn into the experience of building a computer and I wanted to build one.

This story will have multiple parts. I will cover the hardware parts, the assembly, the system installation, the software, and configuration. I plan to organize the notes I made, write down the reasons for the choices I made while assembling the server, and describe the lessons I learned in the meantime.