[Guide] Direct Attached Storage (DAS) - Add up to 16 3.5" drive bays to an existing server for less than $300

Update
Another good option for the large DAS is the NZXT Source 210, with 8 bays native. https://www.newegg.com/Product/Product.aspx?Item=N82E16811146077&cm_re=nzxt_source_210--11-146-077--Product

Objective:
Add up to 16 3.5" / 2.5" bays to an existing storage server, directly attached to the server through SAS->SATA connections. This allows for increased bandwidth compared to NAS solutions, and decreased complexity. In theory, you can add up to 16 drives for each x8 PCI-E slot available in your server. So add as many DAS setups like this as you want! The drives in the DAS will be passed through directly to the host-OS, as if they were internal drives. Therefore, you will be using software RAID or JBOD.

This first part of this guide will detail the parts needed to add 12 drives to your existing setup with a full-size DAS. 16 drives may be added by adding another set of cables and another drive cage. This build will be fully SSD and HDD compatible, so feel free to use any combination of those.

This second part of this guide will also outline a mini DAS build for those that don’t need more than 6x3.5" drives, or if you are using a more 2.5" HDD/SSD focused build. The mini DAS can support 6x3.5" and 8x2.5", or 14x2.5".


Rules for buying used server-grade parts on eBay:

  1. Buy from highly-rated, reputable sellers
  2. When “Or best offer” is available, use it. Sellers will likely discount parts, often up to 30%.
  3. Shop around. There are many resellers selling the same exact parts on eBay, find the one with the best price. Sometimes Amazon or Newegg prices are better.
  4. When in doubt, join the #hardware channel of the /r/plex discord and @JDM_WAAAT with questions in the #hardware channel. I’ll do my best to get back to you.

12/16 Bay full-size DAS Build

Type Item Price (eBay)
Recommended Case CoolerMaster N400 8x3.5" bay $63
External SAS card LSI 9201-16e $44
3x SAS-> SATA cables SFF-8088 -> 4x SATA $20 each / $60 total
PSU EVGA 500W $40
HDD Cage Caselabs 4x3.5" HDD + 120mm fan mount $40
3x SATA power cable 4xSATA power splitter $5 each / $15 total
120mm Fans 5x120mm Fan pack $23
SATA Fan Controller Thermaltake 10 port fan splitter $13
Total $298

6/10/14 Bay mini DAS Build

Type Item Price (eBay)
Recommended Case Fractal Design Node 304 ITX $100 w/ shipping
External SAS card LSI 9201-16e $44
2x SAS-> SATA cables SFF-8088 -> 4x SATA $20 each / $40 total
PSU EVGA 500W $40
2x SATA power cable 4xSATA power splitter $5 each / $10 total
SATA Fan Controller Thermaltake 10 port fan splitter $13
Total $247

About this build:

  • General: This build assumes that you have an existing server with a free PCI-E x8 or x16 slot. One free PCI-E slot is all that is needed in order to add up to 16 drives (SSD or HDD) via an external DAS. This build guide outlines the requirements to connect one DAS. If you would like more than one, just build another!
  • PSU: Any PSU will work. If you find a better deal on a PSU, feel free to take that route. Modularity isn’t a hude deal here because there will be plenty of room to manage cables. Also, we’re only going to be using the SATA cables, so as long as the PSU has 4 SATA power we can split them off into 16 SATA power. The PSU on/off switch will be what turns the DAS on and off. It is helpful to make sure that the PSU select actually has a physical switch, otherwise unplugging / plugging in the cord will be your on/off switch.
  • Case 1 full-size DAS - 12/16 bay: This case is really good value. 8x3.5" are native, and you can add 4 or 8 3.5" or 2.5" by using 1 or 2 Caselabs 3.5" or 2.5" cages. Mount the 2.5" cages with double-sided velcro in a convenient location. Mount the 3.5" cages in the two top 120mm fan locations. Note: fitment up top while using two cages will be tight, and may take some finageling to make it fit - but it will fit. I suggest using the top 120mm fans and rear 120mm fans as exhaust, and the front as a passive intake. Your front 8 drives will be adaquately cooled in this configuration, requiring only 3 fans total. Reminder, if you expand to 16 drives instead of 12, you need another SATA power cable and another SAS->SATA cable in addition to what is outlined above.
  • Case 2 mini DAS - 6/10/14 bay: I love this case. It’s tiny, fits a full size PSU, and natively supports 6x3.5" or 6x2.5" drives, or any combination therein. You can add 4 or 8 2.5" easily by using 1 or 2 Caselabs 2.5" cages, and using doublesided velcro to mount the cage where the motherboard would go. Note: The Caselabs 3.5" cage WILL NOT fit in this case - only the smaller 2.5" cages will fit. Make sure to add an appropriate amount of SATA power splitters and SAS->SATA cales, 1 of each for every 4 drives. The single 140mm fan will be enough to cool however many drives you fit in this case due to the way air flows in this case.

Upgrades, other parts

  1. 2TB Refurbished HDD’s on ebay - look for Western Digital 2003FYPS or similar, they run around $45. Hitachi/HGST 2TB refurbs can run as low as $28 per drive.
  2. Link for Caselabs 120mm 4x3.5" add-on cage - includes mounting hardware, NO FAN INCLUDED
  3. Link for Caselabs 4x2.5" add-on cage - includes mounting hardware
  4. Fan speed reducer (if you don’t want your fans to run full speed) - $7 for 5 pack

Build and setup

  1. Configuring the PSU - First, we need to make the PSU be able to turn on via the switch at the back of the PSU. We will be shorting out the green wire on the 24-pin ATX connector to any other black (ground) wire. This simply jumps the two connectors, simulating what happens when the PSU is plugged into a motherboard and the power button on the PC is pressed. I suggest using a long staple or part of a paperclip. You can wrap this with electrical tape if you wish, but no significant amount of current will be flowing through this connector so it’s not necessary. If you need more information, follow this link: http://www.instructables.com/id/How-to-power-up-an-ATX-Power-Supply-without-a-PC/
  2. Install and re-flash the LSI card in the server - Install the LSI 9201-16e into any free x8 or x16 PCI-E slot. I used the windows application (Megaraid Storage Manager) found here to flash the card with the IT firmware and bios found on LSI’s website found here. The MSM application is available for other OS’s as well. I found this to be much easier than this way, but both work just fine. IT mode passes the drives directly to the host OS, and does not use any hardware RAID features. It’s JBOD (just a bunch of disks)! Don’t forget to restart your server after flashing the LSI card.
  3. DAS Setup - Install the parts into the DAS, starting with the power supply. Mount the HDD’s / SSD’s into the cages or native case mounts, and then wire the SATA power splitter to the drives. hook up the SAS->SATA cables to the hard drives, and router the wires either through the PCI expansion slots on the case or where the motherboard I/O shield would normally go. The SAS SFF8088 ends will connect to the LSI card in the server, but don’t connect that yet. Once your drives and PSU are installed, make sure to connect the PSU to the SATA power splitter and the fan controller. Don’t forget to cable manage! There should be plenty of space to tuck and manage stray cables. Close up the DAS, and plug the PSU into the wall. The only cables coming out of the DAS should be the SFF8088 cables.
  4. Shut down the server - while the server is shut down, plug the SFF8088 ends from the DAS into the server’s LSI 9201-16e. Don’t worry about what ports you use for which cable, it doesn’t matter. You can plug them into any port, even after the RAID is configured. Turn on the DAS via the PSU’s power switch - you should hear the fans and drives spin up.
  5. Turn on the server - the disks should show in the host OS as being configurable for whichever software RAID method you are using.
  6. Notes on using the DAS - The DAS is always the first thing you turn on before turning on the server, and the last thing you turn off after shutting the server down. You can also leave the DAS on between restarts and shutdowns, you do not have to turn it off. DO NOT turn off the DAS while the server is turned on, even if you are not logged in. Doing so could result in DATA loss.

Please feel free to leave a comment or ask questions below.
Keep calm, Plex on!

Thanks for taking the time for this guide JDM. I greatly appreciate your comments and help on reddit as well!!

1 Like