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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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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6answers
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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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5answers
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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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1answer
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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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Can we mount multiple disks as one directory?

Are there way to mount the different disks as one directory? Assuming I have some disks with ext4 partitions: /dev/sda1 1Tb mounted as /store1 /dev/sda2 2Tb mounted as /store2 /dev/sdb1 2Tb mounted ...
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5answers
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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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2answers
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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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3answers
625 views

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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4answers
458 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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2answers
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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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4answers
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How to isolate the failed drive on Dell R710 using RHEL5 with a DELL PERC controller?

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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1answer
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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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1answer
277 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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2answers
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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 ...
6
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1answer
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mdadm and 4k sectors (advanced format)

There are numerous questions on Serverfault about aligning 4k sectors disks, but one thing is not really clear to me yet. I successfully aligned my RAID1+LVM. One of the things I did was use mdadm ...
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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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2answers
337 views

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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2answers
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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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1answer
227 views

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? ...
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1answer
535 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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1answer
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Ubuntu server, gpt partition table, mdadm, grub boot fail

Basic working system details: I used the Ubuntu 12.04 server CD to install a server. I have 4 disks. On all disks I did the following, similar to this howto : created a 2GB swap partition created ...
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2answers
620 views

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 ...
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3answers
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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 ...
6
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1answer
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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 ...
6
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1answer
618 views

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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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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1answer
751 views

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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9answers
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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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9answers
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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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Mac OS X Server 10.6 - Apple's software mirrored RAID worth it?

I am installing an Intel Xserve (Quad core Xeon) with Snow Leopard Server (10.6) on two 80Gb 7200rpm SATA HDs. I created a mirrored RAID set using Disk Utility with those two drives, all went fine. ...
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2 drives “failed” on a 3 drive RAID 5

But I don't believe it. The machine is a Dell PowerEdge 2600 server running Windows Server 2008 trial 32bit (yah, its not supposed to...but it works! [well, it used to]). For the sake of confusion: ...
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7answers
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setup lowcost image storage server with 24x SSD array to get high IOPS?

I want to build let's name it a lowcost Ra*san which would host for our social site the images (many millions) we have 5 sizes of every photo with 3 KB, 7 KB, 15 KB, 25 KB and 80 KB per Image. My ...
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7answers
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Raid 5 with hot spare or RAID 10 with no hot spare?

Yes, this is on of those "do my job for me" questions, have some pity:) I'm at the limit for what I can do with the number of hard drives in a server without spending a substantial amount of money. ...
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4answers
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How do I configure RAID 5, especially stripe size, with 24 x 1.2 TB drives for CentOS 6?

For a Dell R920 with 24 x 1.2TB disks (and 1TB RAM), I'm looking to set up a RAID 5 configuration for fast IO. The server will be used to host KVM VMs that will be reading/writing files of all sizes, ...
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3answers
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Is a large RAID-Z array just as bad as a large RAID-5 array?

For a long time I've heard about how bad an idea a large (>5TB?) RAID-5 array is simply because there's a high risk for another drive to fail. Has RAID-Z1 managed to remedy this for an array of any ...
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Is SAFE new terminology that is replacing RAID? [closed]

I was looking for an external drive enclosure with a RAID controller and found one in Newegg. Looking at Wikipedia, I cannot find information on this "SAFE" terminology. Is this a replacement for ...
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RAID 5 with big SATA disks. Do or don't?

Is it sane to build a machine with RAID 5 expecting to hold around 5 Tb (and able to grow) with 1.5 or 2 Tb SATA II disks? It will be used as audio and documents storage. I already have chosen a ...
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3answers
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Moving a RAID array from one machine to another

I'm not too familiar with RAID arrays, but I plan on making a RAID 5 array for a fileserver. However, once I get the RAID running for a while, I have plans to move it to another machine (with ...
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How can I uprade my software RAID1 set of drives?

I've got two 600GB drives in a software RAID1 setup on a physical Debian server. I want to be able to upgrade the capacity of the server by cloning the drives to a matching pair of 2TB drives. I can ...
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2answers
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Does adding more drives to a RAID 10 Array increase performance?

I'd like to know if I were to add additional drives to an existing Raid 10 if this would increase the speed of the entire array?
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2answers
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Where should my swap partition/s live when using software RAID1? Performance? LVM?

When I search around for example RAID1 installations, it seems that admins tend to place their swap partition under RAID1. To me, it is more intuitive to have two disks, each with a large partition ...
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Does Windows Defrag utility reports fragmentation correctly on a RAID system?

We have a server with a RAID volume. Windows DEFRAG shows very high fragmentation (90%) on the volume. My chief asked if DEFRAG reported fragmentation is correct (or near correct) or not. We don't ...
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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 ...