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Questions tagged [raid5]

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 redundancy and performance (via parallel communication) is required. RAID 5 is a specific implementation.

RAID 5 (block-level striping with distributed parity) distributes parity along with the data and requires all drives but one to be present to operate; the array is not destroyed by a single drive failure. Upon drive failure, any subsequent reads can be calculated from the distributed parity such that the drive failure is masked from the end user. However, a single drive failure results in reduced performance of the entire array until the failed drive has been replaced and the associated data rebuilt. Additionally, there is the potentially disastrous RAID 5 write hole. RAID 5 requires at least three disks.

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Source: wikipedia

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Raid 5 Hard disk corruption

I have got IBM x3650 M4 server. It is configured with Raid 5 & includes 4 SAS hard disk with capacity of 500 GB each. Now the 2 Hard disk are showing as bad. So by replacing the 2 hard drives with new one will the data get rebuild automatically or…
lakhan vasre
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Why does a URE cause loss of array during RAID 5 rebuild?

From what I have read, RAID 5 is problematic with large disks becuase if a single disk fails, you are likely to have an unrecoverable read error while the array is being rebuilt. From what I can gather, this URE prevents the entire array from being…
StrongBad
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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, algorithm 2 [3/3] [UUU] [=================>...] …
user205537
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Safer RAID5 rebuilds using partially failed disks?

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. Obviously this is a significant concern. …
arcticmac
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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 was told by the salesman that while the RAID server…
Pal Hart
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Dell 2950 with 6 disks, is 2 x 3 RAID 5 arrays possible?

I have a Dell 2950 with 6 disks, I'd like 2 RAID 5 arrays 3 disks in each array. The RAID manager only allows me to create 1 array, after the array is created I can't create another. Why would this be? PS I'm going to install Exchange 2010 on this…
Steven
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RAID 5, 2 out of 4 disk drives are foreign

I am in hot water and badly need help. Server Machine is Dell PowerEdge r730. It has 4 hard drives of 1TB. RAID 5 was already configured (Not by me). Now I see this screen at startup. When I press any key, the health manager opens. I see it says…
MJ Khan
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replacing drive in raid 5 array with non-standard disk

I have a Raid 5 array made up of three HP brand 10k rpm SAS-6G drives with 146 gb size. One of the drives is telling me from its LED that it needs replacement. When I ordered a replacement I found that it was the last one in stock and my drive is…
TWood
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Raid 5 recovery

Attempting to recover a 5 Disk Raid wherein 2 of the 5 disks are out of sync. Is it safe to create the raid from 4 of the disks? mdadm --examine /dev/sd*1 > /raid.status grep Role raid.status Device Role : Active device 0 Device Role :…
futurusx
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shell script to get raid controler details

How can I get the RAID 5 controller array details using a shell script command?
Arunjith
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Confusing RAID-5 numbers

raid-5 It's a mixture of 500GB x2 and a 320GB. (465, 465, 299.9 ish effective.) I've never done raid before but I tried to get as close to the pool capacity as I could. The disk space should be equivalent to 2x the smallest disk no? effectively…
Daniel
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Replace RAID 5 without losing system on a Dell r710 Perc6 Debian

I have a Dell r710 running Debian and just got it tuned to my use. It boots from a RAID 5 array of 4x300gb SAS drives. I have just converted some 600gb NetApp drives to 512 sector and they are recognised. How can I migrate the entire system from…
Ed Kemp
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question on I/O stats in linux

In one of our lab machines,I found a disk i/o error suddenly.It was running for a while doing lot of i/o on the disk due to our application processing huge data.My machine is hardware raided which is a RAID5.I heard from my friend an RHCE…
sriram
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RAID5 recreate without loosing data or recovery

I have problem with RAID5 failed. Intel Matrix Storage on Asus motherboard The configuration was - 500 GB NON RAID (System C partition) - 1 TB - RAID 5 with 3 hard drive (System D partition) Main problem is that before failure - array was in…
Krystek
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I cannot expand RAID5 capacity on an Adaptec RAID 71605, an "expand" in ribbon is greyed out

I have 4 disks RAID5 array and want to add additional identical disks in order to expand the capacity. I do everything as instructed, but "expand/migrate" buttons are greyed out, so i cannot do it.
Mike Reznikov
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