RAID stands for Redundant Array of Independent Disks, and is a technology which can provide increased reliability, performance, and/or redundancy by utilizing multiple hard drives simultaneously. RAID can be implemented in a computer via either a hardware or software controller.

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What are my options for a multi-Terabyte home NAS? [closed]

I've got alot of DVDs and have been slowly ripping, encoding, and tagging them and I've nearly filled my WD MyBook 1TB. I'm estimating that I've got about 1.5 or 2Tb to go to complete my current ...
22
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3answers
2k views

Detecting when a server is running on UPS battery

I have a home server (HP Proliant ML310 G4) that I bought from my employer a month or so ago. The server runs Debian Linux and I use it for just about everything. I can get away with doing this ...
22
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5answers
46k views

Which software raid modes does each version of Windows 7 support?

Being familiar with the software raid modes and dynamic disks from the server versions, I was wondering if there is a document or even just common crowd knowledge that indicated what software raid ...
19
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8answers
81k views

How to get an inactive RAID device working again?

After booting, my RAID1 device (/dev/md_d0 *) sometimes goes in some funny state and I cannot mount it. * Originally I created /dev/md0 but it has somehow changed itself into /dev/md_d0. # mount ...
19
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8answers
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Simple mdadm RAID 1 not activating spare

I had created two 2TB HDD partitions (/dev/sdb1 and /dev/sdc1) in a RAID 1 array called /dev/md0 using mdadm on Ubuntu 12.04 LTS Precise Pangolin. The command sudo mdadm --detail /dev/md0 used to ...
18
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3answers
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How can I make mdadm auto-assemble RAID after each boot?

I successfully created a RAID (mirroring) by utilizing mdadm. However, I must run the following commands after each boot: mdadm --stop --scan // to stop /dev/md127 - I don't know where the number 127 ...
14
votes
9answers
17k views

RAID 0 performance gains?

I'm building a new computer over the summer. I'm fairly competent in computer hardware, and am thus building the computer from scratch. I have everything planned out, but I was wondering about RAID. ...
14
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2answers
10k views

Does software RAID 1 in Windows 7 improve read speeds?

Does software RAID 1 (mirroring) in Windows 7 improve read speeds? I'd like to set up RAID 1 to help protect my important documents (yes, yes, I know it's not a backup), but performance is also ...
13
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7answers
12k views

Onboard RAID vs Software RAID

My motherboard, an Asus M4a79t Deluxe, advertises RAID 0/1/5 capabilities. My limited understanding is that onboard RAID is better than software RAID. Is this necessarily true? Is an onboard RAID ...
13
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5answers
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How does parity work on a RAID-5 array?

I'm looking to build a nice little RAID array for dedicated backups. I'd like to have about 2-4TB of space available, as I have this nasty little habit of digitizing everything. Thus, I need a lot of ...
13
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1answer
9k views

Intel Matrix Storage Manager vs Linux Software RAID

The chipset I'm using supports the Intel RSTe technology. It means that I have two options for RAID setup: Ordinary linux software RAID, using mdadm command. RSTe (either by the BIOS or, again, ...
13
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5answers
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Is TRIM supported on RAID 0 configurations for SSD drives in Windows 7?

I know this question has probably been asked at some point in the past, but I am trying to figure out if Windows 7 supports passing TRIM commands through RAID controllers yet. I am trying to decide ...
13
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5answers
3k views

Alternatives to Windows Home Server Drive Extender?

As Microsoft is cutting support for Drive Extender in Windows Home Server v2 (Windows Server Codename Vail is the official name), what are the alternatives to Drive Extender on a self-built machine? ...
12
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10answers
7k views

Looking for an actual experience of RAID 5 2 drive failure? [closed]

I'm wondering if anyone has any personal experience of RAID 5 2 drive failure with large drives? As I understand it, the theory is that with large 1-2TB drives, if one drive fails in the raid set, it ...
12
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2answers
7k views

Can I setup a software RAID in Windows 7 using Virtual Hard Disks?

Well, the title of my question pretty much sums it up, but let me elaborate. The main idea of what I want to do is as follows: 1) I have two separate hard disks, with nearly equal performance. I use ...
12
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1answer
8k views

How do I check Windows 7 Software RAID Rebuild Progress from the Command Line?

I use software RAID on my Windows 7 ultimate box media center. Unfortunately, Windows decides it needs to rebuild my software RAID pair much more often than I'd like. The most common way to see the ...
11
votes
7answers
5k views

What RAID configuration is most appropriate for a home user?

I have a computer for general home use and mild gaming (not upgraded the graphics card so still on AGPx8). It is currently configured for striped access over two 80GB disks. Is this the best option? ...
11
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11answers
56k views

What's the difference between RAID 1 software mirroring and Fake RAID?

I've just ordered two new hard drives for my main desktop and a copy of Windows 7 Professional 64-bit. I'd like to do a clean install of Windows 7 onto the new drives (leaving my old Windows XP ...
11
votes
4answers
1k views

Is it worth buying SSDs for a RAID?

Im seeing people using SSDs for RAID-0 and getting excellent improvements in read/write rates. But now there is a good opportunity to acquire another SSD Force Corsair F60 identical to mine. I'm ...
10
votes
3answers
18k views

How-to change the name of an MD device (mdadm)

Here is the output from mdadm -Esv: ARRAY /dev/md127 level=raid0 num-devices=2 UUID=d89d9d45:9a420812:c44c77eb:7ee19756 devices=/dev/sdb8,/dev/sda8 This is a v0.90 array. The question is as ...
10
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1answer
508 views

Where is the software RAID information actually written?

Like title says, where is the actual information which specifies which disks are being used, what order, etc...? I noticed while installing a linux distro that it was detecting a RAID array without a ...
10
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2answers
2k views

Formula to calculate probability of unrecoverable read error during RAID rebuild

I want to compare the reliability of different RAID systems with either consumer (URE/bit = 1e-14) or enterprise (URE/bit = 1e-15) drives. The formula to have the probability of success of a rebuild ...
9
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3answers
3k views

Any difference between Hardware RAID and Software RAID?

I'm building a new server (Small Business Server 2008), but I can't get the built-in RAID controller (AMD SB700) to work and have basically given up on it ever working with Server 2008. Fine. But my ...
9
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2answers
5k views

Is there a RAID 7?

One of my friends at school was talking about a RAID, he said there was a RAID 7, as to my knowledge no such thing exists. Could someone clarify? I don't think there is but just making sure.
9
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2answers
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Can I set up a RAID 5 with a bunch of drives of different sizes?

I currently have 3 1TB drives, a couple 500GB ones and some 750GB ones. Can I put them all in a RAID 5 configuration or do they need to be of same size?
9
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2answers
1k views

Can a failed Btrfs drive in RAID-1 be replaced live?

I am trying to decide on a filesystem and would like to know if it is possible to replace a failed drive in btrfs RAID without downtime. Suppose I create a new btrfs filesystem using the command ...
9
votes
1answer
5k views

Is it possible to create a software RAID 1 with different sector sizes?

I bought a hard drive of a different model to my main drive and tried to mirrored them, but the following error message came up in Windows 7 Virtual Disk Manager: All disks holding extends for a ...
9
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2answers
1k views

New SSD (Corsair) takes 1-2 minutes before it's found after first boot

My new SSD Corsair CSSD-F60 actually works - using it for boot and system disk (Windows 7 64-bit). But when first (cold-) booting the PC it's not properly found by BIOS and Intel ICH9R Controller. The ...
8
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12answers
4k views

Is RAID 0 as risky as people say it is?

I'm just about to set up my hard drives with RAID 0. Is it really as risky as people say it is?
8
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4answers
6k views

Does fake RAID offer any advantage over software RAID?

Does a fake RAID controller do any useful work or is it just like a place where to store the parameters? I know that Linux offers much more flexibility than my poor on-board controller, but this is ...
8
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2answers
6k views

Solid State Drive Occasionally Freezes For A Minute While OS Is “Beach Balling”

Almost a month ago I bought Intel 330 128GB solid state drive, migrated my data with Intel branded limited-feature Acronis from old HDD to new SSD, optimized with Intel Toolbox and started using it. ...
8
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4answers
2k views

How long does data stay in a RAID cache?

Most higher-end RAID cards have the option to purchase a battery add-on to allow the controller to finish writing the contents of the cache to the drives in the event of a power failure. I setup ...
8
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5answers
2k views

Looking for tips: building a workstation around Xen and GPU pass-through

I'm building my new home machine right now and as usual this will be a heavily overloaded workstation that will serve as development and testing machine, file server and game console (plus I'm adding ...
7
votes
10answers
9k views

Use RAID for desktop computer?

I'm building a new computer over the summer. I'm fairly competent in computer hardware, and am thus building the computer from scratch. I have everything planned out, but I was wondering if I should ...
7
votes
5answers
3k views

Are there any USB flash drives or SD cards which use RAID or redundant storage for additional reliability?

I'm looking to get a fault-tolerant USB flash drive, which saves data to multiple independent locations, whether using RAID or some other means to back up data. Has a product like this ever been ...
7
votes
3answers
2k views

Will mirroring with an SSD improve read performance?

If you use Windows 7 to mirror a volume across an SSD drive and a mechanical hard drive, will the read performance be similar to a single SSD drive? I.e. is Windows smart enough to read from them ...
7
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3answers
3k views

optimal SATA SSD configuration in new PC

I'm sold on SATA SSDs for my next PC but since their prices grow un-proportionally to their size, I'm wondering what would be the best configuration for them (for OS and Programs) would be: 2 SSDs ...
7
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1answer
201 views

SATA III 6Gb/s, is that 6gbit/sec per device, or for the entire controller?

If I have (12) SSD drives in a RAID6, will the max connection speed of each drive be 6Gbps, or is that for the entire controller?
7
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2answers
920 views

Is the speed difference I get from putting my SSD in RAID mode negligible?

I've got two 80GB Gen2 Intel SSDs, currently in RAID 0. I'm about to reformat for an unrelated reason, and I'm wondering if maybe I should just leave them as independent drives. The primary reason ...
7
votes
3answers
5k views

What advantages and disadvantages have Hybrid SSD/HDD RAIDs

I just read about Hybrid RAID arrays consisting of SSDs and common HDDs which are supported by Adaptec's RAID controllers. Does such a RAID configuration provide real advantage? Isn't write ...
7
votes
4answers
22k views

Can a mirrored (RAID-1) disk be plugged into another system to be read?

If I have disks in a RAID-1 array, can I take one of them out and plug it into a different system to be read? This means, on the target system, treating the disk from the RAID array just like an ...
7
votes
4answers
565 views

One of two RAID 1s is not recognized in Ubuntu 13.04

I have a 256GB SSD (Ubuntu/Win8), and two 1TB drives in RAID 1. The problem is that I just recently added another two drives that are 4TB in RAID 1 but they aren't detected in Ubuntu as one drive but ...
7
votes
2answers
1k views

Make two disks appear as one big share on LAN

I bought 2 x 2TB disks for a NAS server, (linux debian). I want to make both drives appear as one big 4TB disk on the LAN. This can be done with software RAID (JBOD) or LVM I suppose. There are other ...
6
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3answers
448 views

How does RAID5 work? [duplicate]

In a raid 5 setup, you get 4 TB of usable space out of 3 x 2 TB disks. How is that possible? Simple minded as I am, I would think that you need 4TB to store your things, and use the remaining 2TB for ...
6
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3answers
4k views

Practical RAID Performance?

I've always thought the following to be a general rule of thumb for RAID: RAID 0: Best performance for READ and WRITE from stripping, greatest risk RAID 1: Redundant, decent for READ (I believe it ...
6
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4answers
3k views

RAID 1 on 2 external HDDs

I have an Ubuntu 12.04 server on my old laptop. Its HDD (160 GB) is too small for the file storage I need, so I'd like to attach a couple of external HDDs to it (through USB ports). The data I'll keep ...
6
votes
4answers
10k views

Start a ZFS RAIDZ zpool with two discs then add a third?

Let's say I have two 2TB HDDs and I want to start my first ZFS zpool. Is it possible to create a RAIDZ with just those two discs, giving me 2TB of usable storage (if I understand it right) and then ...
6
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2answers
6k views

One SSD + two HDD in RAID 1: SSD performance hit?

My SSD based system is starting to feel slow and sluggish, but it used to be lightning fast. I tried to cleanup as much as I could, removed programs from startup, etc. However, one big change I did ...
6
votes
3answers
2k views

One large or two smaller SSDs?

I'm looking at getting a Crucial M225 SSD. Now the question that's on my mind, is is it worth RAIDing these things? In fact are there any RAID downsides particular to SSDs that you don't see with ...
6
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5answers
945 views

Looking for an external RAID storage solution

I'm looking to buy somewhere around 10TB of physical storage for personal use. Ideally it would come in the form of a single HDD array or network storage. I don't have any experience with RAID, but it ...