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Can we combine compact size, high performance, and loads of storage? We’ll give it a shot

Length of Time: 1–2 Hours | Level of Difficulty: Low

The Mission

If you couldn’t tell by now, we’re performance junkies here at Maximum PC. Just last summer, we were crazy enough to build a $30,000 liquid-cooled computer with two PCs inside it. But you can’t drive in the fast lane all of the time. Sometimes it’s better to take a quiet Sunday drive down to the park and have a picnic. That doesn’t mean the meal has to be bland, but we will be shifting gears for a new palate (with a side of mixed metaphors).

For this righ, instead of building for just speed, we’re also building for capacity. But that’s a pretty straightforward challenge; anyone can slap a bunch of hard drives in a case and call it a day. We’re going to up the ante by shoving eight hard drives into a mini-ITX case. At least, that was the original plan before motherboard maladies intruded. Whatever, we like having massive storage options in addition to our turbo-charged gaming PC or A/V production workstation. This way, we can create a library of full-system backups, and stream media to devices, in a discreet and portable form factor.

Hybrid Theory: Big Capacity, Small Form

Rocking Out

If you want to cram a large number of drives into a mini-ITX system, special gear is required. We were originally going to go with the Asrock C2550D4I, which has 12 SATA ports and an integrated lowpower Avoton quad-core CPU, and support for ECC RAM. Unfortunately, we discovered it’s quite finicky about what RAM it will accept, and appears to strictly adhere to modules on the qualifi ed vendor list. After many failed boot attempts and different slot confi gs and half a dozen DIMMs, we had to give up. It’s not just us either, the Internet is rife with people reporting similar problems.

So, we had to switch to Plan B: a conventional Intel Z97 motherboard and Haswell CPU. This cuts our maximum drive count to four, but we could always install a RAID card in the PCIe slot to add more if we wanted. You can also remove a part of the 3.5-inch drive cage to make room for a long card, though this does sacrifi ce one drive tray.

But what kind of mini-ITX case could even hold eight 3.5-inch drives? Enter the SilverStone DS380, whose entire front is a series of drive bays measuring about 11-inches tall. It’s also over 8-inches wide, giving us room for a variety of activities. This case also takes SFF (small form factor) power supplies, and we went with the Silver-Stone ST45SF-G, a bronze-rated unit pumping out up to 450 watts.

Hybrid Theory: Big Capacity, Small Form ingredients

 

1. Step on Board

Our replacement motherboard is the Asus ROG Maximus VII Impact. Compared to Plan A, this one has a full x16 slot, USB 3.0, shielded integrated sound, dualband 802.11ac, and of course, a spot to install a Haswell CPU. (We went with an unlocked model because we didn’t have the locked version handy and this board with a locked CPU would be a crime.) You have to install a couple of modules on the board such as the Wi-Fi.

 

Hybrid Theory: Big Capacity, Small Form step 1

Our max RAM capacity is reduced to 32GB, and we lose eight SATA ports and one fan header. You can install a RAID card to add more SATA ports, instead of the video card, but we wanted a hybrid build. By way of compromise, we slapped in three 6TB hard drives and one high-powered 1TB solid-state drive.

2. Getting Cagey

This is a compact case, so we need to temporarily remove both drive cages to give the board enough clearance for installation. The main drive cage in the front is secured with four small black screws on the side, and two chromed screws underneath the case. Once those are removed, you can slide the drive cage toward the rear, and lift it right out. Then, the 2.5-inch drive cage at the top of the case comes out.

Hybrid Theory: Big Capacity, Small Form step 2

The motherboard has a vertical extension that holds additional voltage regulators, which is attached via two screws. Remove these, line the board’s four corner holes up with the pre-installed standoffs in the case, and screw in the board.

3. All Wired

With the board installed, we can begin hooking it up. We attach all four SATA cables now, since they’re easy to reach with the drive cage removed. The Impact’s audio comes in though a daughterboard. We plug that in, screw it down, and connect the front-panel audio cable to it. There’s an additional minicard to add two fan headers, and another for Wi-Fi. The I/O shield has perforated holes that you tap out and send the Wi-Fi connectors through.

Hybrid Theory: Big Capacity, Small Form step 3

4. By the Power Supply of Greyskull

Since we have the case open, now is a good t ime to install the power supply. It goes in the top, and there’s an intake grill right there for the PSU to get cool exterior air. We take the flatcable kit and connect the motherboard power, CPU power, SATA power, and Molex. Our hard drives will be getting their power from the PSU’s Molex cables; both of them plug into the drive cage’s backplane and provide all the juice needed there. We’d never find an SFF PSU with eight SATA connectors anyway (this one has two).

Hybrid Theory: Big Capacity, Small Form step 4

The motherboard power cable is a bit tricky to plug into the board because it’s nearly flush with the bottom of the case, but we managed to wiggle it in after a few tries. The CPU cable also has one end specifically for the PSU and another for the mobo.

5. Piecing it Together

With the motherboard hooked up, we can drop the drive cages back in. Note that the backplane of the 3.5-inch cage has two data connectors per drive. One is actually for dualchannel SAS drives, while the other is for SATA or singlechannel SAS. (They’re clearly labeled to avoid confusion).

Hybrid Theory: Big Capacity, Small Form step 5

We take the other ends of those SATA cables we plugged into the motherboard earlier, and we attach them to the SATA side of the backplane, one by one. Then we put the cage’s screws back in and unlock the door, which uses a five-sided bit as a key. With the door open, the drive trays slide out from the front. Since the backplane has integrated SATA/SAS connectors, you just put the drive into the tray, attach a few screws, and slide the tray back in. The drive is now installed.

Although we can’t populate the whole cage with drives, three 6TB units give us 18TB, which is a very good start. Plus there’s the 1TB on the SSD, which we’re using to boot Windows. If only we had 10TB drives!

6. In Plane Sight

Since the SATA ports on the board are close to the backplane, we can tuck most of the SATA cabling behind the cage. All three fans have twist ties pre-attached, so they need minimal adjustment. The rear fan cable is a bit tricky, though. Its cable is not sheathed, so the wires are easily snagged. You can tuck away the wires, as there isn’t a fan header particularly close by. You also want to keep it well clear of the CPU’s heatsink, to keep the wire insulation intact. We ended up just stringing it along the bottom of the case. It’s not pretty, but it gets the job done.

Hybrid Theory: Big Capacity, Small Form step 6

The other cables are mostly hidden by the sheer bulk of the 3.5-inch drive cage (which would weigh over 15 pounds after populating all eight trays). This is not a flashy case with a side window, but you’re unlikely to be fiddling with its innards often, so appearance is not a high priority.

 


 

Hybrid Theory: Big Capacity, Small Form callout

1.) These funny-looking cylinders are capacitors that help provide power to the storage devices in the 3.5-inch drive cage. 2.) With 8TB 3.5-inch drives on the way, this eight-tray cage could hold 64TB of data—plus the four-drive 2.5-inch cage. 3.) We wanted to add a third-party CPU cooler for overclocking, but the space here is just a little too tight. 4.) We added a grill to the rear fan, since there’s a non-trivial amount of wiring hanging around the area, even after tidying up.

Fancy Toys Bring High Price and Mixed Results

Ironically, we started with the Asrock C2550D4I because we wanted a more straightforward build. With an integrated CPU and cooler, it cut down on the steps we needed, giving us more time to fiddle with Ubuntu (the CPU on the original board doesn’t support desktop versions of Windows, and we couldn’t justify $700 Server 2012). It’s been a while since we gave desktop Linux a spin, but that’ll have to wait.

As far as we can tell, the C2550D4I is picky as hell with RAM. Asrock has a very short QVL list for RAM and many of them aren’t sold in the United States. After burning hours trying to get the board to POST with a fistful of different modules in every possible configuration, we gave up. But rather than completely bail, we decided to make something of the system, especially since we had some nice hardware waiting in the wings.

Almost no video card would be possible without the removable section on the 3.5-inch drive cage. Not even that shorty Nvidia GeForce GTX 760 that we used in one of the Minecraft builds last month. Even then, the dimensions of the cut-out clearly limit you to a reference-sized card—we ended up with only a few millimeters between the card and the edges of the cage. Luckily, we have several reference units lying around (and we made sure we chose one you could still buy).

Problem Fans

The other half of the equation was Silver-Stone’s cable kit, which is short and flexible. At $30, it’s not a cheap kit, but with over $3,700 already invested, it’s a relatively small expense. You could try using your own cable set, but, for safety reasons, we don’t recommend it. Each power supply’s set of cabling is designed for a specific range of tolerances. Our original power supply was 300 watts and had integrated cables, but only one PCIe connector. We needed two for the GTX 780.

We almost fit a Cooler Master 212 EVO on top of the CPU, but the capacitors on the drive cage’s backplane poke into that space. Putting the fan on the other side of the radiator fin stack would also compel us to reverse the airflow of the rear exhaust fan, or else the rear exhaust and CPU fan would be fighting over the air coming their way. There would be no proper exhaust for the case, and heat would build up. We could’ve experimented with a 120mm closed-loop water cooler, but the build was already in overtime.

We’d consider this build a qualified success but we honestly don’t recommend anyone follow our blueprint. It would have been cool to slap a load of high-capacity drives in there and see what the Asrock CPU-plusmobo combo could handle. At $280, the C2550D4I would also have been considerably cheaper. On the bright side, we get more adaptability with the higher cost and desktop OS driver support. But our price tag is on the high side. You’d probably be fine with an Intel Core i5 CPU, $125-ish mobo, 8GB of RAM, and 250GB SSD. That slashes about $1,000 off the build. Then you can go with much less expensive 4TB or 3TB drives. But like we said, why let the fancy toys collect dust?


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YouTube CopyrightFollow these steps to avoid having licensed music removed from your YouTube videos

If you’ve ever tried to legally inject a copyrighted song into your YouTube video (meaning you licensed it or otherwise own the song in question), you know it can be an exercise in frustration. It’s not that using music is difficult—the problem stems from YouTube’s sometimes overzealous efforts to keep everything on the up and up. Even though you have permission to use an audio track, or own the copyrighted song, YouTube may take down your video, essentially claiming you’re a copyright crook. Have it happen enough times and you might even find yourself banned.

Part of the issue has to do with Content ID, which is a system YouTube uses to look for copyrighted music. It automatically scans every video that gets uploaded and sniffs out potential copyright violations, but one of the problems with Content ID is that it only identifies the song, not the license. Alternately, someone can file a copyright claim on music contained in your video and, well, it can be a hassle.

Well folks, the good news is there’s a relatively easy way avoid the headache of having your video removed from YouTube over false copyright concerns. Here’s how.

Obtain Permission

The first thing you need to do is make sure you have permission to use the copyrighted song you want in your video. Depending on the song, this can be relatively easy or a bit of pain in the backside, and potentially time consuming. Be that as it may, it’s necessary if you’re not trying to skirt the law.

You can request permission from major music labels by using the following links:

For other labels and music rights holders, you’ll need to do some digging on Google, Bing, DuckDuckGo, or whatever happens to be your search engine of choice.

Or Use YouTube’s Catalog of Music

If you don’t want to go out and license music on your own, you can swap out audio tracks on your video using YouTube’s audio swapping tool. Here’s the thing—YouTube possesses over 150,000 tracks that are free to use, and since they’ve all been pre-approved, you don’t have to worry about a copyright claim yanking your video offline.

YouTube Audio
YouTube provides plenty of free music to add to your videos.

You can find step-by-step instructions by clicking here, though if your click finger is sore, here’s what you do:

  1. Go to your Video Manager page, and click the arrow next to Edit on the video you’d like to edit
  2. In the drop-down menu, click the Audio button
  3. Select a track by clicking on it and preview your video with the music track added
  4. Search for a track using the search box, or browse by genre using the Featured Tracks tab
  5. Once you’ve found a track you like, click the Save button, and the new audio will be applied to your video. Audio tracks can be positioned in a precise part of your video using the Position Audio feature.

That’s it, you’re finished, there’s nothing more to see here. For the rest of you, move on to the next step.

Be Audacious and Grab Audacity

If you routinely work with music files, then you’ve probably heard of Audacity. And if not, well, here’s your chance to get acquainted with the program. It’s free, open-source, and works on multiple platforms, including Windows, Mac, and GNU/Linux. You can grab Audacity here.

What we’re going to do with Audacity is ever-so-slightly alter the speed and pitch of the copyrighted song that you licensed. By doing this, it throws YouTube off the scent and greatly reduces the risk that your video will be taken down.

Once you’ve installed Audacity, fire it up and load your song inyo the program. You can either drag-and-drop the music file into Audacity, or load it the old-school way: File > Open and select your song.

With your song loaded into Audacity, go ahead and highlight the length of the track. Since there’s no “Select All” option, the easiest way to do this is to click the gray area on the left-hand side. Alternately, you can scroll until you reach the end of the track, click in the gray area, and drag left until you’ve highlighted the entire song.

Audacity Change Speed
Don’t go overboard or your altered track will sound noticeably different from the original.

After you’ve selected the length of the song, it’s time to alter the speed. Click on Effect > Change Speed. A pop-up box will appear giving you the ability to speed up or slow down a track, either by dragging the slider or entering a percentage. You don’t want to go crazy here, or the song will sound funky, but at the same time, a slight change won’t be enough to duck YouTube’s filter.

We recommend changing the speed by 0.3 percent—it doesn’t matter if you speed it up or slow it down. It will take anywhere from a few seconds to a few minutes to process, depending on the length of the song and your PC. When it’s finished, give the altered track a listen. With such a small change in speed, only the most discerning ears should be able to notice a difference.

Locate Lame
You’ll need Lame to save to MP3 files with Audacity.

If you’re happy with the result, go to File > Export Audio and save the track to WAV or MP3. If you choose MP3, you may get a message letting you know that Audacity needs the file lame_enc.dll. Don’t sweat it—just hit the Download button (or click here) and follow the instructions.

Pitch Imperfect

If changing the speed doesn’t do the trick and/or you want to err on the side of caution, you can also alter the pitch. The steps are mostly the same—load up your music file and highlight the entire track, but this time select “Change Pitch” from the Effect menu.

Audacity Change Pitch
Alter the pitch too much and it will sound like Alvin and the Chipmunks hijacked your track.

Under the Frequency heading, there’s a Percent Change box. We suggest changing the pitch anywhere from 3 to 5 percent in either direction (for slower songs or tracks with an emphasis on instrumentals, like bluegrass, you’ll probably have better results with negative percent changes). Try it one way and give it a listen. If you don’t like the result, go to Edit and select Undo Change Pitch. Try again in the other direction and/or alter the percentage.

Upload and Enjoy!

All that’s left now is to upload your slightly altered, licensed music track to your YouTube video. It’s still possible that a person could manually report your video, so you may want to leave a note letting viewers know that you licensed the copyrighted song(s) in your video.

NOTE: Maximum PC does not condone the stealing of copyrighted material, so we do suggest that you ask for permission whenever possible. 

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RAID 1 and 0: Together, forever

When you’re trying to get the best performance out of multiple drives, a redundant array of independent disks (RAID) is your best bet. There are plenty of RAID modes levels (modes) to choose from, but many favor RAID 10 for its reliability and speed.

RAID 10 is an example of nested RAID, where two or more arrays are integrated into another RAID that is then visible to the system. In the case of RAID 10 (also known as RAID 1 + 0), this means having two or more RAID 1 arrays combined into a RAID 0 array. RAID 10’s sibling is RAID 0 + 1, where the top level RAID 1 array is comprised of two or more RAID 0 arrays.

RAID10 diagram

RAID 10 is an example of nested RAID.

As a result, RAID 10 offers both the great resiliency of RAID 1 with the hot striping action of RAID 0. The only downside is that it requires at least four drives to work. Since RAID 10 stacks a series of RAID 1 arrays together, expanding storage means adding at least two drives, not just one.

As far as speed is concerned, you get all the speed benefits of RAID 0, but instead of speed as a function of the number of drives, speed is calculated as a function of the number of RAID 1 stripes. 

To use RAID 10, there are two methods we’re going to show here: software RAID and FakeRAID. Software RAID is implemented by the OS, and the OS handles the logic for the array. FakeRAID is often denoted by motherboard manufacturers as “onboard RAID.” FakeRAID is still software driven, but that software works at the BIOS level, rather than the OS. 

If you’re only running one OS, or you’ll only need your RAID in one OS, go for software RAID. If you’re going to need to share the RAID 10 array between two OSes, or plan on installing an OS on top of your RAID, go with FakeRAID.

Prepare your hardware

If you’ve been following along in our series, you’ll know that it’s always best to use drives of identical make, model, and capacity when constructing a RAID array. Even if you’re forced to use different makes and models (as we were in our examples), you have to make sure that the drive capacities are identical. Mixing drives will at best result in an array that will performs as if each drive were the slowest one.

When connecting your drives for use in RAID, be sure to use the same interface for the drive. If two drives in your array are using SATA 6Gbps, use the same interface for every other drive you intend to add to the array. If your motherboard has multiple SATA controllers (our Gigabyte board had the built-in Intel controller as well as a Marvell controller), make sure you use the main controller if you plan on using FakeRAID. We had problems getting our BIOS to detect drives that were attached to our motherboard’s additional Marvell controller.

It’s also a good idea to make sure all of the drives in your array are using the latest firmware. Firmware fixes can result in better speeds and fix potential bugs that can wreak havoc on your data.

If you’re going to use FakeRAID, make sure your motherboard has “onboard RAID.” Most recent motherboards do, but if you’re building a server out of an old machine, this is something you should check.

Windows: Storage Spaces and Disk Management

Unlike with other RAID levels like 0, 1, or 5, Windows 8 doesn’t have an obvious option for creating RAID 10 arrays using Storage Spaces. Similarly, Windows 8 can’t combine RAID arrays in its Disk Management utility either. It can however combine RAID 1 arrays created with Storage Spaces with RAID 0 in the Disk Management utility.

To start, hit Win+S and search for “storage spaces” and open the utility. Next, click create a new pool and storage space. You’ll be prompted for administrator access.

You’ll be greeted by a windows showing all the unformatted disks that can be used. Here, you’ll have to decide how you want your disks spread out in your arrays. Remember that you’ll need at least two drives for each RAID 1 stripe. Since we used four drives in our example, we selected the first two drives for our first stripe. Select the drives you want to use and click Create pool.

Create storage space pool

Each pool will represent a RAID 1 array that will be a stripe for RAID 0. Choose your drives for your storage pools accordingly.

Next, the wizard will prompt you to create a storage space in the pool. For Resiliency type, select “Two-way mirror.” This is the equivalent to RAID 1. Don’t worry about the filesystem or drive letter: that will be rendered irrelevant later. However, label each stripe something memorable (like Mirror 1, Mirror 2, etc.) so you’ll be able to find it later. When you’re ready, click Create storage space to create the array.

Create storage space

Give your storage space a drive label so you can find it later.

Once you’re done with the first pool, repeat the steps for every other stripe that you’ll be creating. In our case, we repeated the steps with our remaining two drives.

To tie these RAID 1 arrays all together, we’re going to use Windows’ Disk Management tool. To open it up, search for “Disk Management.”

When Disk Management is open, you should see your disks (RAID 1 arrays) in the bottom part of the window, identified by the labels you gave them. Now, we’re going to get rid of the filesystems on those drives. For each disk, right click on the blue segment and select “Delete Volume.” Be careful to leave your system disks and any other attached drives intact. When in doubt, double-check and cross-reference the drive label with the one shown in Storage Spaces.

Disk Management delete volume

Deleting a volume will remove the selected partition on that disk. 

Once all the RAID 1 disks are clear of filesystems, it’s time to create our RAID 0 array. Right click one of your RAID 1 disks and select “New Striped Volume…” In the popup window that follows, add each of the RAID 1 disks you want to use and click Next.

Assign the RAID 10 array a drive letter. This isn’t necessary, but if you want to use your drive right away, it’s the fastest method to do so. The next screen of the popup window, select the filesystem you  want (NTFS or ReFS), and enter a drive label. You can also enable drive compression here. If you forget, you can always change it later in Windows Explorer. 

Striped volume options

You’ve done the hard part. Now all you have to do is give the volume a name.

The last screen will ask you to review your options. When you’re satisfied everything looks good, click Finish. A final popup will ask you if its okay to convert your drives into dynamic disks. This basically is warning you that you’ll lose any data on them, and that other OSes won’t be able to see them. We’re okay with this, so click Yes.

That’s it! It will take Windows a while to format the drives for use, but when it’s all done, you’ll have a shiny new RAID 10 array.

Next, we’re going to see how Linux and FakeRAID handle RAID 10. (Spoiler alert: It’s much easier.)


 

Linux and mdadm

The great thing about creating RAID volumes in Linux is that it’s so easy. RAID is really important for servers, and like most server software on Linux, it gets a lot of development attention. In our example, we used Ubuntu 14.04 LTS Desktop on a live USB stick.

Ubuntu Desktop doesn’t come with the driver that handles RAID out-of-the-box, so we’ll need to download and install it. Open up a terminal and enter the following command:

sudo apt-get install mdadm

install mdadm

Installing mdadm only takes a couple seconds. 

From here, we can create the RAID 10 array with GUI tools or the command line.

If you prefer GUI, search for “Disks” and open the Gnome Disk Utility (it will appear as “Disks”).

When the window open, look for a check mark at the top of the list of devices. Click the checkmark, and you’ll be able to select a bunch of devices. If you select more than one writable storage device, a button at the bottom will appear with the label “Create RAID.” Select the drives you want to use and click the button.

Select disks for RAID

Make sure to only select the disks you want to use for your array.

In the popup window, select “RAID 10 (Stripe of Mirrors)” as the RAID Level and give the array a name. You can adjust the chunk size (the size of striped data) as well. When you’re done, hit Create.

That’s all there is to it. Easy, right? If you want to feel a bit more like a wizard, you can do the same thing with a couple of command line entries.

First, we need to know what devices are called in the filesystem. You can use lsblk to figure that out:

lsblk -o name,mountpoint,size,type,model

lsblk on Ubuntu

lsblk is handy when you can’t remember devices’ names.

Once you’ve identified the drives you want to use, use the mdadm command to create your array. In our example setup, we used the following:

sudo mdadm –create /dev/md10 –level=10 –raid-devices=4 /dev/sdb /dev/sdc /dev/sdd /dev/sde

We got a couple errors because we had previously used the same drives in another RAID 10 array, so mdadm asked us if it was okay to write over that data. 

mdadm command line

How’s that for a one-liner?

Easy peasy.

You’ll have to wait for Linux to synchronize the drives before you use them, however. Once the array is synchronized, you’ll need to partition, format and mount the array to actually use it.

FakeRAID

Onboard FakeRAID is harder to set up, but is your only real choice if you want your RAID array to be accessible to both Windows and Linux. You can also install an OS on top of a FakeRAID array.

Once your drives are physically installed, boot into your BIOS by tapping the key prompted on startup. The message will say “Press DEL to enter Setup…” or something similar.

Once you’re in your BIOS, look for an option called “SATA mode.” This option is in different places for each motherboard manufacturer, so refer to your user manual if you can’t find it. Once you’ve found the setting, change it from AHCI to RAID. This will let your onboard RAID software know that there are possible RAID devices to be started. When you’re done, save and reboot.

RAID mode

For FakeRAID, switch the SATA mode from AHCI to RAID.

On the next boot, you have to get into the RAID software to set up your arrays. If you have an Intel RAID controller, you may be prompted to hit CTRL+I to start the Intel Rapid Storage Technology (RST) RAID software. The software varies by vendor, so consult your motherboard manual on entering the RAID utility. In this example, Gigabyte’s implementation let us use the RST tools from inside the UEFI BIOS utility.

In Intel’s RST menu, you should see some options and a list of hard drives on your system. Select “Create RAID Volume.” Give your volume a name and select “RAID10 (0 + 1)” as the RAID level.

select RAID level

Intel RST FakeRAID only supports RAID 0, 1, 5 and 10.

Next, select the drives you want to include in your array. Other RST implementations may have you select drives first. Make sure that the drives you select are the correct ones; you’ll lose any data saved on the drives that you use in a FakeRAID array.

On the next boot, your FakeRAID array will appear as a single disk to the operating system. Additionally, RST may display the status of your RAID disks during the boot process, before the operating system loads.

In order for Windows to be able to repair any drives in your FakeRAID setup, you’ll have to install  the appropriate driver. For Intel RST, the driver is available on Intel’s website. In Linux, you’ll have to install mdadm to use the array.

RAID 10 arrays aren’t cheap due to the number of drives you need in order to set them up, but if you’ve got the coin (and the spare SATA connections) to implement it, RAID 10 offers a rock-solid combination of resiliency and speed for your data.


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Striping and parity across three drives, oh my!

Of all the RAID levels that consumers are likely to use on their home systems, RAID 5 is one of the more exotic choices. While RAID 0 and 1 are pretty straightforward, RAID 5 is a little more complex.

As we discussed in earlier articles, RAID 0 stripes data across an array of drives, making reads and writes faster, while also sacrificing redundancy. RAID 1 does the opposite, writing identical data across every drive in the array, creating a redundancy in the event of failure. RAID 5 is somewhere in between.

Intel RST in Gigabyte UEFI BIOS

Like RAID 0, RAID 5 stripes data across an array of drives. However, one of the drives is reserved as the redundant copy of the piece of data. As each block of data is written, the stripes and redundant copy rotate places, so that no single drive fills up with redundant copies (this is called distributed parity). For this to work, RAID 5 requires a minimum of three drives.

When a drive in a RAID 5 array fails, the data can be located somewhere else in the array. If failure occurred on a drive that held a striped copy, the entirety of the data can be found on the drive that holds the parity copy. If the parity is missing, you still have a copy of the data striped across the other drives. On the flip side, if you lose more than one drive, you’ll lose the entire array because parity is distributed across all the drives.

In terms of performance, read operations will be similar to that of RAID 0, as the striped data can be read from several drives at one. Write operations, however, are more like RAID 1, since the parity data is written to only one drive.

Drive space is also pooled, but less so than in RAID 0. In RAID 5, it works a bit differently. Due to the way parity works, if you have three drives, the available space will be equal to a RAID 0 array with two drives. In our examples, we used three 120GB SSDs, which resulted in arrays with 240GB of space.

If you want install an OS on top of a RAID array, RAID 5 will work fairly well, so long as you’re not trying to use it atop an array of multi-terabyte spinning drives. RAID 5 offers more resiliency than RAID 0, as well as significant gains in read operations for loading programs and games.

Prepare your hardware

If you’ve been following along in our series, you’ll know that it’s always best to use drives of identical make, model, and capacity when constructing a RAID array. Even if you’re forced to use different makes and models (as we were in our examples), you have to make sure that the drive capacities are identical. Mixing drives will at best result in an array that will performs as if each drive were the slowest one.

When connecting your drives for use in RAID, be sure to use the same interface for the drive. If two drives in your array are using SATA 6Gbps, use the same interface for every other drive you intend to add to the array.

It’s also a good idea to make sure all of the drives in your array are using the latest firmware. Firmware fixes can result in better speeds and fix potential bugs that can wreack havoc on your data.

If you’re going to use FakeRAID, make sure your motherboard has “onboard RAID.” Most recent motherboards do, but if you’re building a server out of an old machine, this is something you should check.

Windows: Storage Spaces

Creating a RAID 5 array in Windows is just as easy as creating RAID 0 and 1 arrays. It’s important to remember Microsoft uses the name “Storage Spaces” instead of RAID, but the function is pretty much the same.

To start, hit Win+S and search for “Storage spaces” and launch the utility. Next, click  “create a new pool and storage space.” You’ll be prompted for administrator access. Click Yes to continue.

You’ll be greeted by a windows showing all of the unformatted disks that can be used. Select all the disks you want in the array and click “Create pool.” You’ll have to select at least three to be able to create a RAID 5 array.

Windows 8 Storage Spaces Select Drives

In a perfect world, we’d use identical drives, but sometimes you have to use what you’ve got lying around. Reliability and speed could be negatively affected by using different drives.

Next, give the pool a name and drive letter. The name will appear as the drive label. Select NTFS as the file system. For Resiliency type, select “Parity,” which is the equivalent to RAID 5. When you’re ready, click Create storage space to create the array.

Windows 8 Storage Spaces

If you want to remove a RAID array for any reason, simply click Delete next to the storage space you want to remove. To remove the pool, remove all of the storage spaces in it first.


Linux: mdadm and disks

Creating a software RAID 5 array in Linux takes only two terminal commands. In Linux, the program mdadm (we like to pronounce it “madam”) is what we’ll use to set up the array.

First things first, you need to get the RAID software. You’ll need to download and install mdadm from your software repository. It’s pretty common, and is included in most software repos. In Ubuntu, type the following command:

sudo apt-get install mdadm

The command will install mdadm for you, along with a dependency called Postfix. Postfix is an SMTP service that sends emails. The reason it’s included is because if a drive fails or something else happens to your array, the system can alert you with an email. That’s great for IT administrators, but Postfix is a PITA to administer. In many cases, you can just set the program to use no configuration if you like. If you do take the time to set it up, it can give you early warning when drives fail.

Once mdadm is all set up, all you need to do is use the following command:

sudo mdadm –create /dev/mdX –level=5 –raid-devices=[number of drives (3 or more)] [drive name] [drive name] [drive name] [etc]

The above command will vary based on the size of your array, and how you’d like to name it. RAID devices are generally named /dev/mdX where X is the index of the array. Drive names can be any valid Linux device path, e.g., /dev/sda or /dev/disk/by-uuid/[UUID].

If you’re not sure how Linux has identified your drives, you can use lsblk to identify them:

lsblk -o name,model,mountpoint,size

Once you create your array, you’ll have to wait while the drives synchronize, which may take several minutes.

Gnome Disks utility in Ubuntu

The Disks utility is an easy-to-use GUI that allows you to create RAID arrays out of disks and partitions.

You can also create RAID arrays in Linux using the GNOME disk utility. In Ubuntu, search for “Disks” and open the utility. On the left side of the window, click the checkbox above the list of drives. Then, select the drives you want to use to create an array and click Create RAID.

Using onboard FakeRAID

Onboard FakeRAID is harder to set up, but is your only real choice if you want your RAID array to be accessible to both Windows and Linux. You can also install an OS on top of a FakeRAID array.

Once your drives are physically installed, boot into your BIOS by tapping the key prompted on startup. The message will say “Press DEL to enter Setup…” or something similar.

Once you’re in your BIOS, look for an option called “SATA mode.” This option is in different places for each motherboard manufacturer, so refer to your user manual if you can’t find it. Once you’ve found the setting, change it from AHCI to RAID. This will let your onboard RAID software know that there are possible RAID devices to be started. When you’re done, save and reboot.

On the next boot, you have to get into the RAID software to set up your arrays. If you have an Intel RAID controller, you may be prompted to hit CTRL+I to start the Intel Rapid Storage Technology (RST) RAID software. The software varies by vendor, so consult your motherboard manual on entering the RAID utility. In this example, Gigabyte’s implementation let us use the RST tools from inside the UEFI BIOS utility.

In Intel’s RST menu, you should see some options and a list of hard drives on your system. Select “Create RAID Volume.” Give your volume a name and select “RAID5 (Parity)” as the RAID level.

Gigabyte UEFI Intel RST interface

The Gigabyte motherboard we used allowed us to access Itel RST from inside the UEFI BIOS utility. Each motherboard manufacturer will do things differently. Consult your user manual to figure out how to access Intel RST.

Next, select the drives you want to include in your array. Other RST implementations may have you select drives first. Make sure that the drives you select are the correct ones; you’ll lose any data saved on the drives that you use in a FakeRAID array.

On the next boot, your FakeRAID array will appear as a single disk to the operating system. Additionally, RST may display the status of your RAID disks during the boot process, before the operating system loads.

RAID 5 is a bit different and a little more complex than RAID 1 or 0, but it offers a compromise between the two extremes. This special RAID level will give you some wiggle room, just be sure not to ignore a drive failure. If all the drives are identical and one goes down, others may soon follow.


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Striping and parity across three drives, oh my!

Of all the RAID levels that consumers are likely to use on their home systems, RAID 5 is one of the more exotic choices. While RAID 0 and 1 are pretty straightforward, RAID 5 is a little more complex.

As we discussed in earlier articles, RAID 0 stripes data across an array of drives, making reads and writes faster, while also sacrificing redundancy. RAID 1 does the opposite, writing identical data across every drive in the array, creating a redundancy in the event of failure. RAID 5 is somewhere in between.

Intel RST in Gigabyte UEFI BIOS

Like RAID 0, RAID 5 stripes data across an array of drives. However, one of the drives is reserved as the redundant copy of the piece of data. As each block of data is written, the stripes and redundant copy rotate places, so that no single drive fills up with redundant copies (this is called distributed parity). For this to work, RAID 5 requires a minimum of three drives.

When a drive in a RAID 5 array fails, the data can be located somewhere else in the array. If failure occurred on a drive that held a striped copy, the entirety of the data can be found on the drive that holds the parity copy. If the parity is missing, you still have a copy of the data striped across the other drives. On the flip side, if you lose more than one drive, you’ll lose the entire array because parity is distributed across all the drives.

In terms of performance, read operations will be similar to that of RAID 0, as the striped data can be read from several drives at one. Write operations, however, are more like RAID 1, since the parity data is written to only one drive.

Drive space is also pooled, but less so than in RAID 0. In RAID 5, it works a bit differently. Due to the way parity works, if you have three drives, the available space will be equal to a RAID 0 array with two drives. In our examples, we used three 120GB SSDs, which resulted in arrays with 240GB of space.

If you want install an OS on top of a RAID array, RAID 5 will work fairly well, so long as you’re not trying to use it atop an array of multi-terabyte spinning drives. RAID 5 offers more resiliency than RAID 0, as well as significant gains in read operations for loading programs and games.

A note about RAID 5 and SSDs

We talked to software engineer Sam Baughman about SSDs in RAID 5. He told us that RAID 5 has the potential to wear out SSDs faster than normal due to the way RAID 5 parity data works.

TRIM doesn’t work as you’d expect; 1/(N) of each of the N drives will always be allocated, even when the array is empty, due to presence of RAID 5 parity data,” he said. “The fewer drives in the array, the more significant the impact on SSD lifespan.”

Baughman has been a software engineer for over 15 years and specializes in device drivers for stoage devices.

TRIM, in case you didn’t know, helps the OS extend the liffetime of an SSD during delete operations. TRIM basically says, “Hey, these blocks aren’t being used, you’re cool to clear and write over that data.”

“I’ve tested this on Linux, you will definitely see TRIM on the data blocks, but at least on the kernels I used in the 3.10 series, you’d never see a TRIM of the parity chunks, because parity is never ‘freed’,” Baughman said. “Logically it’s possible for MD (Linux’s RAID driver software) to do it, but the overhead would be significant and require its own metadata.”

So basically, RAID 5 could chop down your SSD’s lifespan if there are a lot of delete and write operations you’re performing. Spinning HDDs don’t have this problem at all, since TRIM isn’t an issue.

We used SSDs in our example because that’s what we had lying around. Before using RAID 5 with SSDs on your system, consider if you’re willing to absorb the extra wear and tear. If you think you might replace the SSDs before they start to wear out, it may not be an issue.

RAID 0 and RAID 1 rock with SSDs though, and TRIM works flawlessly with Linux MD on those levels,” Baughman said.

Good to know, Sam.

Prepare your hardware

If you’ve been following along in our series, you’ll know that it’s always best to use drives of identical make, model, and capacity when constructing a RAID array. Even if you’re forced to use different makes and models (as we were in our examples), you have to make sure that the drive capacities are identical. Mixing drives will at best result in an array that will performs as if each drive were the slowest one.

When connecting your drives for use in RAID, be sure to use the same interface for the drive. If two drives in your array are using SATA 6Gbps, use the same interface for every other drive you intend to add to the array.

It’s also a good idea to make sure all of the drives in your array are using the latest firmware. Firmware fixes can result in better speeds and fix potential bugs that can wreack havoc on your data.

If you’re going to use FakeRAID, make sure your motherboard has “onboard RAID.” Most recent motherboards do, but if you’re building a server out of an old machine, this is something you should check.

Windows: Storage Spaces

Creating a RAID 5 array in Windows is just as easy as creating RAID 0 and 1 arrays. It’s important to remember Microsoft uses the name “Storage Spaces” instead of RAID, but the function is pretty much the same.

To start, hit Win+S and search for “Storage spaces” and launch the utility. Next, click  “create a new pool and storage space.” You’ll be prompted for administrator access. Click Yes to continue.

You’ll be greeted by a windows showing all of the unformatted disks that can be used. Select all the disks you want in the array and click “Create pool.” You’ll have to select at least three to be able to create a RAID 5 array.

Windows 8 Storage Spaces Select Drives

In a perfect world, we’d use identical drives, but sometimes you have to use what you’ve got lying around. Reliability and speed could be negatively affected by using different drives.

Next, give the pool a name and drive letter. The name will appear as the drive label. Select NTFS as the file system. For Resiliency type, select “Parity,” which is the equivalent to RAID 5. When you’re ready, click Create storage space to create the array.

Windows 8 Storage Spaces

If you want to remove a RAID array for any reason, simply click Delete next to the storage space you want to remove. To remove the pool, remove all of the storage spaces in it first.


Linux: mdadm and disks

Creating a software RAID 5 array in Linux takes only two terminal commands. In Linux, the program mdadm (we like to pronounce it “madam”) is what we’ll use to set up the array.

First things first, you need to get the RAID software. You’ll need to download and install mdadm from your software repository. It’s pretty common, and is included in most software repos. In Ubuntu, type the following command:

sudo apt-get install mdadm

The command will install mdadm for you, along with a dependency called Postfix. Postfix is an SMTP service that sends emails. The reason it’s included is because if a drive fails or something else happens to your array, the system can alert you with an email. That’s great for IT administrators, but Postfix is a PITA to administer. In many cases, you can just set the program to use no configuration if you like. If you do take the time to set it up, it can give you early warning when drives fail.

Once mdadm is all set up, all you need to do is use the following command:

sudo mdadm –create /dev/mdX –level=5 –raid-devices=[number of drives (3 or more)] [drive name] [drive name] [drive name] [etc]

The above command will vary based on the size of your array, and how you’d like to name it. RAID devices are generally named /dev/mdX where X is the index of the array. Drive names can be any valid Linux device path, e.g., /dev/sda or /dev/disk/by-uuid/[UUID].

If you’re not sure how Linux has identified your drives, you can use lsblk to identify them:

lsblk -o name,model,mountpoint,size

Once you create your array, you’ll have to wait while the drives synchronize, which may take several minutes.

Gnome Disks utility in Ubuntu

The Disks utility is an easy-to-use GUI that allows you to create RAID arrays out of disks and partitions.

You can also create RAID arrays in Linux using the GNOME disk utility. In Ubuntu, search for “Disks” and open the utility. On the left side of the window, click the checkbox above the list of drives. Then, select the drives you want to use to create an array and click Create RAID.

Using onboard FakeRAID

Onboard FakeRAID is harder to set up, but is your only real choice if you want your RAID array to be accessible to both Windows and Linux. You can also install an OS on top of a FakeRAID array.

Once your drives are physically installed, boot into your BIOS by tapping the key prompted on startup. The message will say “Press DEL to enter Setup…” or something similar.

Once you’re in your BIOS, look for an option called “SATA mode.” This option is in different places for each motherboard manufacturer, so refer to your user manual if you can’t find it. Once you’ve found the setting, change it from AHCI to RAID. This will let your onboard RAID software know that there are possible RAID devices to be started. When you’re done, save and reboot.

On the next boot, you have to get into the RAID software to set up your arrays. If you have an Intel RAID controller, you may be prompted to hit CTRL+I to start the Intel Rapid Storage Technology (RST) RAID software. The software varies by vendor, so consult your motherboard manual on entering the RAID utility. In this example, Gigabyte’s implementation let us use the RST tools from inside the UEFI BIOS utility.

In Intel’s RST menu, you should see some options and a list of hard drives on your system. Select “Create RAID Volume.” Give your volume a name and select “RAID5 (Parity)” as the RAID level.

Gigabyte UEFI Intel RST interface

The Gigabyte motherboard we used allowed us to access Itel RST from inside the UEFI BIOS utility. Each motherboard manufacturer will do things differently. Consult your user manual to figure out how to access Intel RST.

Next, select the drives you want to include in your array. Other RST implementations may have you select drives first. Make sure that the drives you select are the correct ones; you’ll lose any data saved on the drives that you use in a FakeRAID array.

On the next boot, your FakeRAID array will appear as a single disk to the operating system. Additionally, RST may display the status of your RAID disks during the boot process, before the operating system loads.

RAID 5 is a bit different and a little more complex than RAID 1 or 0, but it offers a compromise between the two extremes. This special RAID level will give you some wiggle room, just be sure not to ignore a drive failure. If all the drives are identical and one goes down, others may soon follow.

UPDATE: We got in contact with a software enginer who writes drivers for storage devices. He told us RAID 5 can wear out SSDs faster than normal, so we added the section “A note about RAID 5 and SSDs” with an explanation why.


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