RAID, an acronym for Redundant Array of Independent Disks (sometimes incorrectly referred to as Redundant Array of Inexpensive Disks), is a technology that provides increased storage functions and reliability through redundancy. -Wikipedia

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How to select the best Stripe Size when configuring a RAID Array

There are various "references" on the Internet that delve into some discussion about what factors to consider when selecting a particular RAID stripe size (4KB to 128KB or more) for an array of disks, ...
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LSI 9285-8e and Supermicro SC837E26-RJBOD1 duplicate enclosure ID and slot numbers

I am working with 2 x Supermicro SC837E26-RJBOD1 chassis connected to a single LSI 9285-8e card in a Supermicro 1U host. There are 28 drives in each chassis for a total of 56 drives in 28 RAID1 ...
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Boot from software RAID 1 on Windows Server 2008 R2

I have a Windows Server 2008 R2 x64 system with a single hard drive, and I have a spare hard drive of same size/model that's not being used. I was thinking about dropping in the new drive and setting ...
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Which block sizes for millions of small files

I have 2x 4TB Disks in hardware RAID1 (it might be a LSI MegaRaid) on Debian Wheezy. The physical block size is 4kB. I'm going to store 150-200 million of small files (between 3 and 10kB). I'm not ...
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How to resize RAID1 array with mdadm?

I've running Ubuntu 11.04 (kernel 2.6.38-11). I replaced 2x160GB with 2x500GB drives. They are configured as RAID1. The partition tables show the right sizes. Here's sfdisk: # sfdisk -d /dev/sdb # ...
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Will spinning down hard disks create Linux Raid problems?

I'm setting up a server that will need to be accessible 24/7 but will be rarely accessed (archive storage). To save heat/power, I'm thinking of setting hard disks to spin down using hdparm. However, ...
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RAID with 4 drives offers very minimal speed improvement

Setup 1.5TB x 8 on a SANS Digital enclosure configured into two sets of 4 drives and connected to a Windows Server 2003 computer over eSATA. They are all identical Seagate Barracuda ST31500341AS ...
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Most efficient RAID configuration with 6 disks?

I have a hand-me-down server that I'm setting up at home and it's got 6 72Gb hard disks (as well as 2 18Gb drives that I'm using for the OS). What is the best way to configure those 6 drives? Should ...
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Why are there RAID models where there are more than one parity disk?

I was just wondering how multiple "parity disks" would work, since it seems that doing so might defeat the purpose of having a parity.
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24TB RAID 6 configuration

I am in charge of a new website in a niche industry that stores lots of data (10+ TB per client, growing to 2 or 3 clients soon). We are considering ordering about $5000 worth of 3TB drives (10 in a ...
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RAID 0 recovery

I know the theoretical answer is "not possible". But theory and practice do not always match. So I'm wondering if you know any trick to recover something... Is there any chance to recover anything ...
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What purpose does the battery serve on a battery-backed caching RAID controller if the server is on an uninterruptible power supply?

Is the battery redundant if the server is on a properly-sized UPS? There is an option to force write-back mode and I want to understand the risk. It is my understanding that it helps against power ...
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howto plan RAID for ESX

eight 300GB SAS drives are available. Can ESX be put on one disk as RAID-0 and others as RAID-5 ? so that in the event of disk failure data (VMs) are safe. if os disk RAID-0 fails could that be ...
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ZFS on top of Hardware Mirroring, or just mirror in ZFS?

I have an IBM x346 with dual 3.2Ghz Xeons and 2x36GB 15k SCSI disks. I'm running an entirely ZFS-based install of FreeBSD 8.1. I can configure the bios to mirror the two disks, and then put ZFS on ...
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SQL Server Transaction Log RAID

We have three SQL Server servers, and each server has a about five or six databases on it. We are in the process of moving these servers to a new SAN and I am working on the best RAID configuration. ...
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RAID level confusion (MegaCli vs megasasctl output)

I'm utterly new to working with LSI MegaRAID controllers and I'm confused as to what RAID level I am actually running. My server is equipped with 4 disks, 4TB each and I would like to have them ...
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SW SSD Raid 1 over HW RAID 10

A provider(data center) recommended I go with 1TB SSDs in a software RAID 1 over HW RAID 10 with mechanical drives. Their quote: Typically SSDs are most reliable than RAID cards and since you ...
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Does ZFS replace the need for hardware/software RAID?

I want to provide protection against data loss on my servers. Typically, I'd use hardware RAID 1 or 5, but I've been reading up on ZFS. Is it correct that ZFS itself provides RAID 1 or 5 like data ...
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What is the fastest and safest RAID combination for SATA drives?

I wonder what is the fastest and safest RAID combination for SATA drives and general use (some write, mostly read)? RAID 0 is fast but utterly unsafe, RAID 1 is safe but slow, RAID 5 is safe but not ...
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Poor read performance on Dell Perc H200 RAID10 with (4) 1TB 7200rpm 64MB drives

I am seeing only 50MB/s reads: ensnare@box:~$ sudo hdparm -tT /dev/sda [sudo] password for ensnare: /dev/sda: Timing cached reads: 4592 MB in 2.00 seconds = 2296.48 MB/sec Timing buffered disk ...
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Dell Perc 6/i and 3TB drives?

Does the dell Perc 6/i controller support 3TB drives?
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ZFS Like Alternatives on Windows

Conceptually, and I don't think I am alone here, I love the concepts of ZFS. You can create one big disk, everything is stored on multiple drives, and you can grow and shrink the pool and drive at ...
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What is the best way to configure 6 disk raid for SQL Server + OS?

I'm setting up a SQL Server on Win 2k8 with following hardware: 6 x WD RE3 500G SATA PERC H700 I've read some suggested that putting log file and OS on its own RAID1 while the rest of data is on ...
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explain md's raid10,f2

I know how most of the various RAID's work. But I stumbled on the recommended raid10,f2 mode while researching linux software raid. I don't really understand how it works on 2 or 3 disks. could ...
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Would unplugging a drive simulate a drive failure?

I just set up a RAID 1 array, 2 2tb drives mirrored. I am wondering what will happen if one were to fail. Would unplugging one of them be a valid test? I am using the Onboard controller of an asus ...
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How long should rebuilding 250GB take? [closed]

In a PowerEdge 1900 have I a hardware RAID 5 of 5x250GB disks + 1 hot spare 250GB. Disk 2 have errors, so I forced it offline in the raid bios to replace it. Now it have been rebuilding to the hot ...
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472 views

mdadm: Replacing array with entirely new drives

I have a server with three 500GB drives, with most of my data in a RAID5 configuration spanning the three of them. I just purchased and installed four 1TB drives, and the intention is to move off of ...
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What is the best way to configure a new ZFS server with lots of storage?

Assume the following drive setup (with ZFS): Controller 1 Drive1 Drive4 Drive7 Drive10 Controller 2 Drive2 Drive5 Drive8 Drive11 Controller 3 Drive3 Drive6 Drive9 ...
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RAID rebuilding seems to have stopped

My server was running a RAID 1 array with two disks. One of those disk failed today and was replaced. I've copied the GPT partition to the new hard disk (sda) with: sgdisk -R /dev/sda /dev/sdb ...
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How to isolate the failed drive on Dell R710 using RHEL5 with a DELL PERC controller? [duplicate]

I've a failed drive reported in my RAID5 running on a Dell R710 using RHEL5 with a DELL PERC controller. Is there a method to determine which drive it is? Can I do this at the command line?
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I have a 21TB array but only 16TB is visible from Windows

CONTROLLER Raid Controller: 3Ware 9650SE-24M8 Disks: 21 x 1TB RAID5 Stripe 64KB WINDOWS OS: Windows Server 2003 SP2 32x Disk: Dynamic 19557.44GB Volume: Capacity 15832.19GB I guess my array ...
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does adding heaps of drives to a raid 0 increase performance?

does adding heaps of drives to a raid 0 increase performance? i know that two drives in a striped raid will usually be faster than a single drive but will i notice a difference in performance between ...
6
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687 views

How do you connect more than 4 drives to a LSI 9361-4i MegaRAID controller?

I’m fairly new to proper hardware RAID having only used it in pre-built server machines before, but on the recommendation of some friends who work for datacentres I’ve bought an LSI 9361-4i MegaRAID ...
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Disk/RAID Monitoring for HP Proliant Servers and Ubuntu 12.04

How can I monitor the status of the hard disks and the RAIDs of an HP Proliant server using Ubuntu 12.04. In Ubuntu 10.04 I could use the cciss-vol-status to query the RAID status periodically but ...
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Do any software RAID solutions support the TRIM command?

This is a broad question -- I'm not asking about a particular RAID level or OS.
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RAID1: Which disk will be mirrored?

How does a RAID1 system determine which disk to use as the source and which disk to use as the destination when mirroring? Assume for instance the following scenario: A RAID1 array is created with ...
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2answers
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VMWare ESXi 5 - Expanded RAID 5 array - cannot access datastore

I'm using VMWare ESXi 5 and had a 2 TB RAID 5 setup on an HP DL360 with a P400i RAID card. I added two more 1 TB drives and using the SmartStart ACU, added the drives and expanded the logical disk. ...
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How to do the equivalent of Synology Hybrid Raid on Linux myself?

http://forum.synology.com/wiki/index.php/What_is_Synology_Hybrid_RAID%3F Synology is just Linux and uses LVM. How do their tools automate LVM to achieve what they call their Hybrid Raid?
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Reusing a drive from an array

I read the question here Reusing Raid 5 Drive? but I'm not sure it applies 100% to my situation. What is the standard practice when removing a drive from an array to use as a spare for another array? ...
6
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1answer
819 views

Is it possible to enable RAID 1 on an already in-use HP Proliant DL380 G5

I have a HP Proliant DL380 G5 with two HDDs in RAID 0 (Stripe)(72GB+72GB). It has been running Windows Server for quite a while now and has 30GB of occupied space on a stripted volume. I've now ...
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Do all mirrored pairs in a RAID 10 configuration need to be homogeneous in size?

I was planning to expand an existing raid 10 array composed of four 1TB disks with the addition of two 2TB drives. Then I wondered whether, despite the configuration of RAID10 (striping of mirrored ...
6
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3answers
10k views

Dell OpenManage Server Administrator - doesn't display storage devices

I'm running CentOS 5 on a Dell PowerEdge R200. I have installed OpenManage Server Administrator specifically to monitor the HDDs (x2 250GB RAID1) in the machine and alert of any issues or failures. I ...
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Can I convert a 1 disk RAID 0 to RAID 1?

This is dangerously close to question 18957, but it isn't quite the same. One of my logical drives on my P410i is a single disk RAID 0 (because I was short sighted at the time). It's now warning ...
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Areca - expanding a raid by swapping out disks for larger ones

What I am looking to do is, one by one, replace the drives in my current raid array (in a 1680i). After the drives are replaced by their larger counterparts, I want to do an online expand of the ...
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Do dell perc 6i cards support online expansion of a raid 1 array when both drives have been replaced with larger ones?

Do Dell perc 6i cards support online expansion of a raid 1 array when both drives have been replaced with larger ones? For example the the Logical Drive 0 (LDO) has two member 73gb drives. We have ...
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Linux fails to reassemble RAID array after disk upgrade

I have an Ubuntu (9.10) machine with 4 SATA disks. Each disk is partitioned identically, with the first few gigabytes set aside for a RAID 1 array (/dev/md0) for the boot volume, and the ...
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2 drives, slow software RAID1 (md)

I've got a server from hetzner.de (EQ4) with 2* SAMSUNG HD753LJ drives (750G 32MB cache). OS is CentOS 5 (x86_64). Drives are combined together into two RAID1 partitions: /dev/md0 which is 512MB ...
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4answers
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Is it necessary to have RAID in a virtual machine?

I have a Windows 2008 Enterprise on RAID 10 running Active Directory, Hosted Exchange, and a web server on HyperV VMs. Do I need a virtual RAID for Exchange? If so, why? Edit: thanks everyone for the ...
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RAID strategy - 8 1TB drives

I'm setting up a backup storage device- This machine has Windows Server 2008, on a separate boot drive. It has 8x 1TB drives, and uses a hardware RAID card. My question is, which RAID configuration ...
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Use of 2.5" Laptop Drives in a Server?

We're acquiring several 1U servers with (8) 2.5" drive slots. Although we can use either SATA or SAS, there is a large price variance as soon as you order 16 or 24 of these drives, so we are looking ...