Because storage has become so inexpensive, what’s stopping you from building your own disk-to-disk backup system for a fraction of the cost of a large storage area network? I am going to walk you through the process of building your own 16-terabyte, disk-to-disk backup system for around $5,000.
First, let’s go over the parts list. The RAID card is probably one of the most important decisions, because it is the part you will depend on the most. I chose an Areca ARC-1261ML . This is a 16-port SATA card that uses PCI Express. If you require more than 16 channels, the next size is a 24-port. This RAID card has a nice web admin interface, sends e-mail alerts about activities within your RAID system, and is easy to manage.
Next, I included 18 WD Caviar Black 1TB  hard drives. Sixteen of the drives are plugged into my RAID card, one is a spare kept outside the system, and the last is my operating system drive. These hard drives come with 32 megabytes of cache and are backed by a five-year replacement warranty. You will also want to purchase some long SATA cables, because the hard drives normally do not come with cables, and if they do, they are too short. I suggest cables at least 18 inches long. You might want to buy them in different colors for each hard-drive bank.
The case for this setup has five hard-drive banks, and each bank holds four hard drives. I also installed a DVD burner into the system. Any DVD burner will do. An Intel Q6600  CPU with 8 gigabytes of Crucial memory  is plugged into my Gigabyte GA-G31M-ES2L  motherboard. The quad-core CPU provides plenty of horsepower, and the Gigabyte Micro ATX motherboard has just the basics you’ll need for this backup solution.
This motherboard comes with its own video card and 10/100/1000 network port. The Norco RPC-4020 4U rack-mountable case I chose has plenty of room inside, includes five fans for cooling and can hold 20 hot-swappable hard drives. Toss in a Corsair TX650W  power supply to provide plenty of stable power, and we are all set. If you are going to rack-mount this server, pick up a RackSolutions 4 post rail kit .
One last thing to mention is network bandwidth. Depending on how much data you need to back up each night and the length of your backup window, you might want to buy an additional dual- or quad-port Gigabit Ethernet card and set up an Ether Channel on your switch. This could provide 2 to 4 gigabits of network speed to your server. Consider an Intel Gigabit VT quad port server adapter .
Now that we have all the parts, the fun is in putting them together and turning on the computer when you are done. Take all your parts out of the boxes and put them on a flat surface (not your carpet). Carpet creates static electricity, and that is something we want to avoid.
First, address the case, since everything goes in it. You will receive a metal IO shield with the packaging of your motherboard. Replace the one in the case with the one that came with the motherboard. Also, screw in any extra spacers to make sure you have one spacer in the case for each screw hole in the motherboard. These spacers prevent the motherboard from short-circuiting. I always place the motherboard in the case a few times just to make sure I have enough spacers.
Now, before you put the motherboard in, you have to install the power supply. This is a pretty simple process. Typically, there are four screws on the back of the case to which the power supply needs to be bolted. I always install my CPU and heat sink/fan on the motherboard before I place the motherboard in my case. I do this mainly because some heat sinks require special brackets to work properly, and you must install them before the motherboard is in the case.
When placing the motherboard in the case, be careful how you grip it, and watch those corners as you are lowering it in. There are plenty of little resistors you can accidentally bend or break during this process. Once the motherboard is secured, install the memory chips and fasten all the power connections from the power supply to the motherboard. This is when you should reference the manual and find out the exact use of each port on the motherboard.
There will also be power, HDD LED and reset button cables from the case that need to be plugged into the motherboard. From here, you can install the CD-ROM and RAID card. The RAID card should fit snugly in the PCI Express slot on the motherboard. Then you can start placing the hard drives in the hard-drive trays. Once the hard drives are installed, all that is left is plugging in the power and data for the CD-ROM and hard drives.
One tip: Label your SATA cables and hard drives. Your RAID card has 16 channels, which means you’ll have 16 SATA cables and 16 hard drives. Use some sort of label maker to tag the cable going from the RAID card to the hard drive, and also label the front of the case on the removable hard drive cage. This will make things much easier to troubleshoot when you are having RAID issues. Also make sure you wire-tie your cables together. Even energy-efficient hard drives create a decent amount of heat. Keeping the inside of the case neat and tidy will provide greater airflow and lower temperatures.