Questions tagged [raid-5]

A type of RAID redundancy that includes parity data spread across a number of member disks

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31
votes
5answers
50k views

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 ...
28
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2answers
85k views

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?
21
votes
3answers
131k views

How do I reactivate my MDADM RAID5 array?

I've just moved house which involved dismantling my server and re-connecting it. Since doing so, one of my MDADM RAID5 arrays is appearing as inactive: root@mserver:/tmp# cat /proc/mdstat ...
15
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10answers
9k 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 ...
13
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2answers
23k views

How to calculate the final RAID size of a RAID 5 array?

What is the formula for working out the final RAID size of a RAID 5 array knowing the number of disk and the size of each disk?
11
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7answers
41k views

Should I use “Raid 5 + spare” or “Raid 6”?

What is "Raid 5 + Spare" (excerpt from User Manual, Sect 4.17.2, P.54): RAID5+Spare: RAID 5+Spare is a RAID 5 array in which one disk is used as spare to rebuild the system as soon as a disk fails (...
10
votes
3answers
32k views

How to force mdadm to stop RAID5 array?

I have /dev/md127 RAID5 array that consisted of four drives. I managed to hot remove them from the array and currently /dev/md127 does not have any drives: cat /proc/mdstat Personalities : [linear] [...
9
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1answer
6k views

RAID5 vs RAID4 purpose of floating parity

I still did not get why is RAID5 better than RAID4. I understand both computes parity bits that are used for recovering if some failure occurs, the only difference is in storing those parity bits. I ...
8
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3answers
5k 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 ...
8
votes
1answer
1k views

Find files affected by bad blocks with md-raid5 and LVM

I've been doing a lot of research on this topic over the last few weeks - and I think I'm close to completing my recovery, as much as is possible at least. To make a long story short, I'll just ...
8
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2answers
794 views

Data Recovery from RAID5 disk - Promise Pegasus with Apple OSLion and Thunderbolt connection

I have a Promise Pegasus R6 - 12 TB RAID 5 disk for major storage purposes. One of the six 2TB hard disks were dead and the company provided me with a replacement. When the disk was inserted it ...
7
votes
1answer
2k views

RAID 5 Array: Probability of Failing to Rebuild Array

I have a Qnap ts463u-rp data storage array, which contains 4x4TB HDD. my question here is, is it safe to configure 3x4TB as RAID 5? because from what I understood, it's not recommend to configure ...
6
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3answers
966 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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2answers
6k views

Bad performance with Linux software RAID5 and LUKS encryption

I have set up a Linux software RAID5 on three hard drives and want to encrypt it with cryptsetup/LUKS. My tests showed that the encryption leads to a massive performance decrease that I cannot explain....
5
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3answers
4k views

Hardware RAID - what happens if the motherboard or controller fails?

I want to set up a RAID 5 array in a machine that has an intel motherboard. It has built in raid (sata). My concern is what happens if the motherboard fails? How can I take those hard drives ...
5
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2answers
1k views

Is Btrfs vulnerable to RAID write hole effect?

If not, does it mean that Btrfs in RAID mode is fully resistant to power failure?
5
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3answers
2k views

RAID5 / RAIDZ - is it possible to enlarge without losing data?

If I have a RAID5 with 4x1TB drives, and then in, say, a year I decide to upgrade to 4x2TB, can I swap out one drive at a time, then let the parity rebuild, even if it's mixed-size drives? Obviously ...
5
votes
1answer
3k views

4 x 2TB drives, safe to use RAID-5? What is failure rate?

I've read a number of opinions on the risks of running a RAID-5 using 4 x 2TB drives. Apparently the failure rate of the 2TB drives is so high that there is less redundancy than is generally expected. ...
5
votes
4answers
13k views

Ubuntu Server 14.04 - RAID5 created with mdadm disappears after reboot

This is my first question on superuser, so if I forgot to mention something, please ask. I'm trying to set up a home server which will be used as file server and media server. I installed Ubuntu ...
5
votes
1answer
544 views

A weird issue relate to ext4/lvm/raid-5 after partition recovery

I have 3 hard disks, in the following paragraphs named /dev/sda, /dev/sdb and /dev/sdc, newest came first. Note: /dev/sdc has one primary partition /dev/sdc1, one extended partition /dev/sd2, and 3 ...
4
votes
3answers
17k views

Why is RAID5 disabled in windows 8?

I want to create a RAID 5 array in windows 8 with 5 Dynamic Hard Disks and it is grayed out. If this is not possible why not hide that option. If it is possible why it is disabled? after your ...
4
votes
3answers
625 views

Several questions about software and onboard RAID 5

I have a few questions on how software and onboard RAID 5 compare: Is there any way to add a disk to an existing RAID 5 array using either software or onboard RAID? All motherboards I'm interested in ...
4
votes
1answer
1k views

What will happen with my RAID5 after motherboard change?

Currently I have ASUS P5Q-EM and 3 HDDs in RAID5 using its on-board RAID controller Intel ICH10R. I want to buy new motherboard, for example, Gigabyte GA-EQ45M-S2 which also has on-board RAID ...
4
votes
1answer
3k views

Is it safe to stop a RAID 5 expansion?

I'm having some issues expanding a RAID 5 array on a Synology DS413. The drive has gone from 3 x 3TB WD Green drives to 4 x 3TB. I started an expansion operation and it's been stuck at about 60% and ...
3
votes
4answers
3k views

Upgrading from poor performing RAID5 array

After much investigation and the purchase of PCMark7, I believe I have identified the root cause of my PC system's performance issues -- my RAID5 disk array. The PCMark7 scores are listed below. My ...
3
votes
2answers
501 views

What would you see if you tried to mount a single drive from a RAID 5 Array?

The title pretty much sums it up - if someone were to mount a single drive from a software RAID 5 array, what would they see? Would it point to being part of a RAID array, appear as encrypted data, or ...
3
votes
1answer
342 views

Degraded RAID5 after complete disk failure - What to do Now?

I am running OMV 3.0.99 on my NAS. I have set up a RAID5 (with mdadm) containing of three 5TB WD RED drives. I have set up the RAID using the OMV GUI back in the day (2016). Recently one of the disks ...
3
votes
1answer
235 views

“Breathing” sound from Linux File Server

I have a Ubuntu file server and it makes the oddest sound. I can hear a HD making a "breathing" type sound, like the disc spins up for a moment and then cycles down. It happens on a very regular ...
3
votes
1answer
989 views

How to find and delete corrupted files to avoid backing them up

The Problem I have a broken Windows Server software RAID-5 array that I would like to backup, but I want to avoid backing up all the broken files. I'd really love for there to be some kind of script ...
3
votes
2answers
2k views

Testing software RAID5 by pulling a HDD live. Bad idea?

I'm running Ubuntu Server 10.10, with software RAID5 and LVM running on top of that. I have four 2TB HDDs. I also have a separate boot drive with incremental full-system snapshots that run every four ...
3
votes
1answer
330 views

Storage Spaces out of space

I'm using Windows 10 Enterprise. I have four identical 3TB disks set up in a Storage Space pool. Each disk shows up as providing 2.72 TB to the pool. I create a storage space with REFS and resiliency ...
3
votes
2answers
2k views

mdadm: safest way to grow RAID 5 (4x2TB) with 2x4TB

My situation:I am currently running a RAID 5 with 4x2 TB disks and would like to grow the array with 2 x 4 TB disks. The goal would be that there is a RAID 5 with 4 x 4 TB (the two 4 TB disks and two ...
3
votes
1answer
579 views

Interesting Windows install issue with RAID and an SSD

I have been trying for days to solve this issue, so any help would be appreciated. Here is the issue: I have a Gigabyte GA-890FXA-UD5 motherboard. Here is a link to the manual and pages starting at ...
3
votes
1answer
995 views

ubuntu 10.04 softRAID 5 partition scheme

I'm trying to create a RAID 5 array which will contain the Ubuntu installation itself. I tried this partition scheme: 2.0 TB for / 6.0 GB for swap This was as per the instructions provided by ...
3
votes
0answers
605 views

RAID 5 array degraded - Intel Matrix Storage Manager suddenly says all 4 disks are “Non-raid disks”

Long story short, I have a linux (ubuntu 10.04 LTS) server with a 4 disks configured as a 2 TB RAID 5, set up with Intel Matrix Storage Manager v8.0.0.1038 in BIOS. My power went out, and the UPS ...
2
votes
3answers
3k views

In a RAID 5 disk array, does recovering a drive increase chance of another drive failing?

If you have a basic RAID 5 array of 3 or more hard drives, and one fails, does this increase the chance of one of the other drives failing and making the full recovery impossible? If every one of the ...
2
votes
1answer
520 views

How to plan a RAID 5 for expandability?

I'm planning on building a home file server with a few 2 TB drives and I wanted to use software RAID 5 under Linux (most likely ubuntu). Before I start, I wanted to know how easy is it to expand a ...
2
votes
1answer
4k views

Degraded RAID5 and no md superblock on one of remaining drive

This is actually on a QNAP TS-509 NAS. The RAID is basically a Linux RAID. The NAS was configured with RAID 5 with 5 drives (/md0 with /dev/sd[abcde]3). At some point, /dev/sde failed and drive was ...
2
votes
3answers
427 views

SATA Card/RAID Controller - Covering Both Economically

I have been researching RAID (specifically RAID 5) for the last couple weeks. I have seen arguments for both sides, whether to use it, whether to use software versus hardware, and some arguments in ...
2
votes
3answers
106 views

How is Data Recovered when a RAID array fails

I am thinking of using hardware RAID (levels 5 and 10) on my computers. What I don't get is how is data recovered when something goes bad and the RAID array fails (RAID Card problem or anything else). ...
2
votes
1answer
318 views

convert full-disk RAID5 array to partition-based array?

I have a RAID 5 array, md0, with three full-disk (non-partitioned) members, sdb, sdc, and sdd. My computer will hang during the AHCI BIOS if AHCI is enabled instead of IDE, if these drives are plugged ...
2
votes
1answer
249 views

re-assemble out-of-date raid5?

I need help with my raid5 after it crashed through bad sectors. Previously I could re-assemble it with # mdadm --assemble --force -v /dev/md0 /dev/sde1 /dev/sdf1 /dev/sdg1 /dev/sdh1 /dev/sdi1 but ...
2
votes
1answer
1k views

Is it safe to transfer files to a raid 5 array while it is re-synching?

I have a newly created raid 5 array in windows server 2008 (software in windows disk mamanger) and it is resynching... Is it safe for me to start transfering/copy files to the volume while it is ...
2
votes
2answers
399 views

Recover from failed recovery of software RAID5 failure

I have the pleasure ;-) to have been handed the task to try to get data off a server that had a RAID5 array problem and a failed attempt to recover it. Background: the computer in question is some ...
2
votes
2answers
1k views

Recovering data from a Silicon Image SiI3114 RAID

I have a set of 3 disks in RAID 5 originally created with a Silicon Image SiI3114 on-board RAID controller. The old motherboard is dead. The new motherboard (which has a different raid controller) won'...
2
votes
1answer
662 views

Software RAID 5 with Multiple Partitions (one encrypted partition)

Can I have multiple partitions using Software RAID 5 on an Ubuntu Server? For example, say using a 4 drive RAID 5 setup, I want one massive partition for storage and a second smaller but encrypted ...
2
votes
3answers
1k views

Incorrect md5sums on downloaded files

I have an Ubuntu 10.04.1 LTS linux server which is experiencing some weird issues... I just tried to download a 440 MB tgz archive over HTTP using wget, and when expanding it with tar -xzf filename....
2
votes
1answer
979 views

Is it possible to convert a btrfs RAID5 to a RAID6 with the same disks without losing data?

How would I convert an existing RAID5 (single parity) btrfs setup to a dual parity RAID6 configuration given enough free available disk space, using the same disks, without swapping out data ? ...
2
votes
1answer
61 views

Onboard RAID w/ Recovery

I am looking at purchasing the ASRock Z87 Extreme 6ac and I was unclear on if I should use onboard RAID or a dedicated card. My system will be well enough off that I won't have to worry too much on ...
2
votes
1answer
4k views

LaCie NAS failed - Recover Raid 5 From bad device

here is my problem: I have a 5disk (Seagate 2To) RAID5 working with a NAS LaCie 5big. Each disk is still working but the NAS device has failed and it refuses to boot with HDD inside (LaCie helpdesk ...