RAID (redundant array of independent disks, originally redundant array of inexpensive disks[1][2]) is a storage technology that combines multiple disk drive components into a logical unit. Data is distributed across the drives in one of several ways called "RAID levels", depending on what level of ...

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how to determine which drive belongs to which slot on raid 5

i have an HP DL380 G8 machine with 4 hard drives of same size and running on raid 5. unfortunately during a service process of our data center one of the junior team members pulled out all four hard ...
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49 views

Raid 5 verifying

Good day every one, i all ready read this RAID 5 detects write errors? I have raid 5 on "3 ware" controller i want to ask: - do i need run from time to time verify schedule or i can use only ...
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1answer
91 views

logical drives on HP Smart Array P800 not recognized after rebooting

We had a Smart Array P800 configuration working fine (RAID5). Physically, we have a disk enclosure (like this) connected with a Linux Server. Here is what happened: This server was accidentally ...
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2answers
65 views

Linux software-RAID4/RAID5 and CPU usage

In case of RAID4 or RAID5, for each stripe of data bits, a parity bit is stored. For example if I write 0 to drive A and 1 to drive B, then parity bit 1 is stored to drive C. Isn't this a huge load to ...
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2answers
60 views

Is mdadm RAID Toast?

I took all my drives out and put them onto a new cpu/mobo. (upgrading) I boot up and mdadm claims it can't boot my degraded RAID. /dev/sdb sudo mdadm --examine /dev/sdb /dev/sdb: ...
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1answer
36 views

2 disk RAID5 Linux software array

(I've posted this on Serverfault as I suspect it a bit to technical for Superuser. If I'm wrong please move it where appropriate) I am remotely looking at a device which identifies as ReadyNAS ...
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0answers
19 views

dmraid lists disk as “spare”, even though it was part of the array

It was setup as a RAID5, 4 disk array of /dev/sdc -> /dev/sdf. sdf failed, leaving the array in a degraded but operational state. A misguided attempt to restore the array led to one of the working ...
2
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0answers
56 views

Why don't enterprise RAID controllers support migration from RAID 5 to RAID 10?

I've been doing some research on the possibility of live migration from RAID 5 to RAID 10 and I'm curious as to why it seems that most RAID controllers (particularly Dell's PERC controllers) don't ...
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0answers
23 views

Recovering Linux soft raid 5, disk stays as spare

I got disk failure on my Centos Linux soft raid 5 array (mdadm). I replaced one of the disk and started to rebuild the array. Next time I checked the status, the rebuild was failed. This is the ...
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0answers
15 views

Expanding a RAID 5 array on Adaptec

Ive got a RAID 5 array setup on an Adaptec 7805. The current array is setup on conn 1 (4 disks). And ive added a new disk to conn 0. All same capacity and type. How can I expand the array on ...
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1answer
28 views

Raid5 status is checking means?

I noticed the following messages on my system: Personalities : [raid1] [raid6] [raid5] [raid4] Md3 : active raid5 sda5[0] sdc5[3] sdb5[1] 3858519040 blocks super 1.2 level 5, 512k chunk, ...
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2answers
43 views

Deleting Intel RAID 5 Volume Without Losing Data [closed]

I wish to stop using RAID 5 and return to a series of individual drives. How can I do this without losing the data? I'm using intel rapid storage technology
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1answer
92 views

RAID 5 30TB File storage - filesystem and strip size on large files

Nowadays my storage is 6TB and as I will grow up to 30TB in few months I would like to hear some tips/recommendations on filesystem and element strip size to not to have problems in future. 90% of ...
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4answers
105 views

What are the chances of two disks in a RAID5 going out on the same day?

I have a Perc H710 configured as a RAID5 with 4 attached 3TB Seagate 7200rpm hard drives. Two months ago, I got these spurious errors that led me to believe the my controller was bad. I replaced the ...
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0answers
30 views

Creating RAID5 on PowerEdge 2900. Have 4 Physical Disks, but only recognizes 3. Why?

I have a PowerEdge 2900, I also have 4 physical Disks (2-160GB & 2-750GB) in loaded in the top bay. When executing RAID5, the execution only recognizes 3 physical disk (not all four). Can you ...
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1answer
210 views

Qnap TS-410 deleted folder by accident anyway to recover data (raid 5 / ext4)?

I am not in a very good situation at the moment, and bit stressed! I have a Qnap nas (TS-410), this operates on a Marvell 6281 800MHz CPU, while I SSH'ed into the Nas box, I deleted the wrong folder ...
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1answer
160 views

3ware card in RAID-5 configuration slow and causes load when writing

I have a 1Gb/s bandwidth between my computers. The source can actually read and send data at 25MB/s via SSH. My test file is 4GB, I use scp without compression for the test transfer. The rate is ...
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2answers
145 views

Windows 2003 Server R2 system partition full - move and/or expand

PROBLEM: My System (C:) and Data (D:) partitions are full and I need to expand them or move them to larger drives. SPECS: Dell PowerEdge 2900 server Adaptec 39320A SCSI adapters Dell Perc 5/i RAID ...
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1answer
156 views

3Ware 9500s Raid array not visible in Windows 7 x64 disk management - latest firmware and drivers

I bought a used 3Ware 9500s-4LP raid controller from Ebay (the old 3ware 8506-4lp didn't support RAID arrays over 2TB, but it was working), installed it in my server and attached it to the SATA ...
0
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1answer
26 views

mdadm grow operation giving nonstop libata errors

Running Debian 7, mdadm 3.2.5. I issued a command to grow a 5 disk, 3 spare raid 5 array to an 8 disk, 0 spare raid 6 array: mdadm --grow /dev/md0 --level=6 --raid-devices=8 ...
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0answers
43 views

Safer RAID5 rebuilds using partially failed disks? [closed]

There have been lots of articles posted recently about how RAID5 is dangerous because of long resilver times, and in particular because of increasing chances of encountering a URE during the resilver. ...
3
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1answer
61 views

ZRAID1 pool size bigger than expected

I have 3x 4TB drives for a ZRAID1 config (single parity drive) After running zpool create data zraid1 sdb sdc sdd I have a volume that's 10.9T in size, which is what I would expect from a stripe ...
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0answers
70 views

Replace a slowly dying drive in Linux software raid5

I have the same problem as in Can I "atomically" swap a raid5 drive in Linux software raid? i.e. a Linux software raid with 3 RAID5 disks where one disk is showing smart errors but isn't ...
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1answer
92 views

Recoving from a software RAID 5 disk failure

I'm putting together a cheap NAS box and I've read some articles about raid5 not being as robust as I'd imagined. I wanted to get some answers to the following questions before I proceed. I'm ...
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1answer
134 views

Questions on increasing RAID 5 array

I'm kind of new to RAID and before I go about increasing the size of ours I would like to get some feedback on if I'm going about this the correct way. I have included as much information as I can ...
3
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1answer
107 views

RAID 5 drive upgrade

We have an HP ProLiant ML350 G5 server with an 8-bay RAID 5 array configured on a Smart Array E200i controller. The system volume and data are on the same logical drive. The drives are 72GB each and ...
2
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2answers
75 views

Must a disk be formatted everytime it is removed and reinserted into a raid5 server?

I'm very new to RAID servers, in fact I'm new to any kind of server management, so please forgive me if this question is badly phrased. I'm considering buying a RAID5 server with four 4TB drives. I ...
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1answer
42 views

Should I run extended offline self tests using smartd?

A while ago I setup smartd on all my servers do do a daily "Short Offline" test and a weekly "Extended Offline" test. The config for that is "-s (S/../.././00|L/../../7/04)". Today I noticed one of ...
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0answers
106 views

syncing mdadm event count

I had a disk die in my level 5 RAID and before I could replace it, my RAID crapped out while I was copying some data onto it. Reading the RAID kernel wiki on RAID recovery I've tried forcing an ...
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0answers
39 views

How to Recover from a RAID 5EE with a Bad Stripe?

I am familiar with swapping out drives when a drive in a RAID fails. However, I have never lost data before. My Adaptec controller is reporting that the RAID 5EE logical device has bad stripes. I ...
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3answers
414 views

mdadm raid5 recover double disk failure - with a twist (drive order)

Let me acknowledge first off that I have made mistakes, and that I have a backup for most but not all of the data on this RAID. I still have hope of recovering the rest of the data. I don't have the ...
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0answers
89 views

Fsck Errors on raid 5 Enclosure

We have a server (running ubuntu), with an eSATA attached 5 disk enclosure, running hardware RAID 5, that has (had?) an ext4 file system on it. So the enclosure uses RAID 5 to mux the 5 drives ...
2
votes
1answer
98 views

What is the Mean Time to Failure (MTTF) of a RAID5?

Given the MTTF T of an individual drive (say, 100000 hours) and the average time r it takes the operator to replace a failed drive and the array-controller to rebuild the array (say, 10 hours), how ...
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47 views

wrong # of devices in raid set after dmraid -ay ubuntu 10.04 server

After restarting my server i got (initramfs) prompt. Then i did dmraid -ay for activating raid devices. Then am getting errors as follows, wrong # of devices in raid set " device name" /dev/sda ...
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2answers
152 views

Recovering RAID5 array after zeroing wrong superblock

I have a raid5 array on 4 disks, sda1, sdb1, sdd1 and sde1. sdd1 was removed but is a healthy drive. While attempting to re-add it, I accidentally zeroed out the superblock for sdb1. sdb1's data is ...
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0answers
50 views

2 identical systems but different harddisk benchmarks results

I have 2 Dell pe2950 with a raid5 configuration. They are identical inconfiguration, however if I do a harddisk benchmark with ATTO Disk Benchmark I get very strange results. Both machines are of ...
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135 views

Get S.M.A.R.T. Info on Marvell Controller (RAID 5)

I have Windows 2003 R2 x64 and RAID5. Array controller is Vendor 11ABh Marvell Technology Group Ltd. Device 6485h MV64460/64461/64462 System Controller, Revision B Subsystem ...
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1answer
525 views

Linux RAID5 Optimal Chunk Size

I bring up, yet again, the ever-present question of how to best optimize disk structures. In my organization, we have a 14TB Linux software RAID array dedicated to storing backups made using Symantec ...
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1answer
49 views

Preparing for RAID5 failure [closed]

I've got an Ubuntu system with a bunch of hard disks in it acting as my home router, DHCP server, file server, etc. Twice in the past 24 hours it has suddenly decided to set the root filesystem to ...
0
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3answers
56 views

Raid 5 scsi fault

I have no much knowledge about servers and I was looking all day around the internet about finding a solution to my raid 5 problem. All of a sudden two disks failed. The server won't boot (HP ...
2
votes
1answer
142 views

How to grow mdadm RAID5 into degraded state?

mdadm - v3.2.5 - 18th May 2012 Currently have: Version : 1.2 Creation Time : Tue Jun 25 19:03:31 2013 Raid Level : raid5 Array Size : 2930135040 (2794.39 GiB 3000.46 GB) Used ...
2
votes
1answer
129 views

missing files after reassemble of RAID-5

I had to open my file-server's housing on Sunday to replace a faulty fan. What I didn't see was that one of the sata-cables was not properly connected. The 1st thing I did after a reboot was a check ...
0
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1answer
1k views

What Block Sizes and Stripe Sizes will cause performance issues using RAID5?

I'm trying to understand Block Size and Stripe Size. I realize this could apply to more configurations than just RAID5, but i am interested in RAID5 specifically, because I'd like to understand the ...
0
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1answer
44 views

replace a healthy drive in Raid5 on NAS

Good day! I have a 4 disk Iomega NAS. The config is: 4x2TB RAID5, 4.4 allocated, 2.3TB used, and i kept 1TB as available, but not allocated. Nothing has failed, but while 3 disks are 7200 rpm and ...
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0answers
42 views

3ware Raid Driver for Redhat

I am trying to install RedHat 5.6 64 bit on SuperMicro Server. And I created Raid5. But when I started the OS installation . Redhat prompted me to select the Driver for Raid which i downloaded. But it ...
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1answer
220 views

Grub2 w/ RAID5 and btrfs “error: unknown filesystem”

I have a Virtual Machine (in ESXi 5.1) running Ubuntu Server 12.04. When I try to boot my system I grub2 tells me "error: unknown filesystem". I've tried booting a Live CD then reinstalling grub from ...
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1answer
596 views

Replacing Hard drives/RAID array Dell Poweredge 2900

I have a Dell Poweredge 2900 that I'm upgrading from 4x SATA 250GB Drives in a RAID 5 situation to 2x SATA 1TB Drives in a RAID 1 situation. The box is running Windows Server 2003, with a PERC5/i ...
0
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1answer
68 views

RAID5 Bad Superblock, not booting to OS

I've been running Ubuntu 12.04 LTS for about 6 months on a computer that has 3 180gb SSDs in EXT4 RAID5 configured through the motherboard's BIOS. The OS froze and computer had to be forced down. On ...
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votes
3answers
550 views

What are the main points to avoid RAID5 with SSD?

My understanding is that an SSD has a limited amount of writes. RAID5 performs many writes due to parity information across the drives. So reasoning states that RAID5 would kill and lower the ...
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1answer
149 views

Will configuring a server with RAID 5 and (2*500gb) + (2*1TB) work?

I'm currently setting up a DELL server, which came with 2*500gb disk drives but is configured in RAID 1. I want to increase the total capacity of the disk storage to at least 1TB. Now with it being ...