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 do I migrate disks from one Dell PE 2850 to another?

I had a Dell PE 2850 die and I need to move its SCSI disks over to another PE 2850. These disks were in RAID1. I tried moving them over and just hoping the PERC would do the right thing, but it ...
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1answer
94 views

Disabling damaged RAID 1 to read from healthy HDD

One of the HDDs in my software RAID 1 on a dedicated server is damaged. The customer support is slow to respond. I would like to transfer all data I need to another server, but file access is ...
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2answers
4k views

How to use SAS Expander with RAID card?

I've doing some researches since few days and I haven't really got an answer to my question. I am in the process of building a huge file server for the company I work for. We bought a server case ...
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3answers
758 views

Why is the 9650SE RAID1 not showing the full size of the disks?

This is a follow-on to How can I grow a 3Ware 9650SE RAID1 under ESXi 5.0? I've successively replaced 1TB drives in my RAID1 with 2TB drives hoping that I can grow the datastore I've got in ESXi 5.0. ...
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2answers
8k views

LSI RAID monitor reports “Consistency Check inconsistency logging disabled”

I have a server with a LSI MegaRAID 9261-8i controller. Recently I started getting alerts like this one: Controller ID: 1 Consistency Check inconsistency logging disabled, too many ...
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2answers
360 views

Proliant raid controller in a PC

Does anyone know or have experience installing an HP array controller in a standard PC? I'm interested if it would be possible to use a P400i with a SAS-SATA cable using standard Western digital ...
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2answers
283 views

One of my drives thinks that it is part of a raid array, if I delete the array (which is broken & empty) will I lose data?

I had a striped RAID array a long time ago. One of the drives failed and I just used the other drive as a stand alone disk. I have now switched my BIOS back to RAID mode and have created a RAID5 array ...
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4answers
778 views

Can someone explain the physical architecture of RAID 10 in complete layman's terms? [duplicate]

I am a newbie in the world of storage and I am having a hard time digesting the physical architecture of some of the RAID levels. I am particularly interested in RAID 10, and 50. I asked the question ...
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2answers
3k views

data lost with RAID5 on proliant DL360 when drives fail

For some reason the Array Controller on my Proliant DL360 G6 couldn't recognize 2 of the 6 750GB drives I am running in a RAID 5 configuration with VMware ESXi 5.1. When I rebooted the server I chose ...
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1answer
294 views

Move raided hard drives between identical servers, preserving data

I have a raid array of hard drives in a Sun x4600 that need to be moved out, and another Sun x4600 ready to accept those hard drives. The problem is: in my limited experience with servers, it seems ...
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1answer
546 views

Having problem with P410i smart array controller

Please advice me how should i solve my RAID controller problem. The problem is; The system doesn't detect RAID controller. I am using HP proliant DL360 G6 server with P410i smart array controller ( 0 ...
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2answers
2k views

Is it possible to run LSI SAS 9211-8i PCI-E 8 in PCI-E 16 Slot?

I just bought an LSI SAS 9211-8i HBA(Host bus adapter) to use with my new hardware. I realized after looking at the card that it required an x8 slot and my new mobo only x16 available. I keep on ...
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1answer
3k views

When using software RAID and LVM on Linux, which IO scheduler and readahead settings are honored?

In the case of multiple layers (physical drives -> md -> dm -> lvm), how do the schedulers, readahead settings, and other disk settings interact? Imagine you have several disks (/dev/sda - /dev/sdd) ...
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4answers
21k views

Recommended disk/partition setup for a SQL Server

I'm looking for some advice regarding the best way to set up my disks/partitions for SQL Server. Here are some of my major concerns: How should the SQL files be seperated (data files, logs, temp)? ...
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2answers
7k views

How to upgrade a ZFS RAID-Z array to larger disks on OpenSolaris?

I'm planning on installing OpenSolaris on my home server (right now it has Linux) and I would like to know how to prepare for upgrading the server to have larger hard drives in the future. Now the ...
10
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1answer
7k views

Easy to expand Linux software RAID 5 with XFS. Best practices?

I use my Ubuntu machine as a file server for Windows/Linux/Mac clients using a Samba share. I need it to be easily expandable by just adding more hard drives without having to move any data back and ...
18
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4answers
3k views

Software vs hardware RAID performance and cache usage

I've been reading a lot on RAID controllers/setups and one thing that comes up a lot is how hardware controllers without cache offer the same performance as software RAID. Is this really the case? I ...
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7answers
5k views

How many SMART sector reallocations indicate problems?

I have a NAS appliance that is just over a month old. It is configured to email me alerts generated from the hard drives' SMART data. After one day, one of the hard drives reported that a sector had ...
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9answers
7k views

To improve SQL performance, why not just put lots of RAM rather than having faster hard disks?

People keep telling me that in order to improve an SQL server's performance, buy the fastest hard disks possible with RAID 5, etc. So I was thinking, instead of spending all the money for ...
18
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6answers
11k views

Is bit rot on hard drives a real problem? What can be done about it?

A friend is talking with me about the problem of bit rot - bits on drives randomly flipping, corrupting data. Incredibly rare, but with enough time it could be a problem, and it's impossible to ...
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4answers
9k views

Hardware RAID Controller Support for SSD TRIM

Do any hardware RAID controllers available today support TRIM? If not, do any manufacturers have target dates for supporting TRIM? Should I even care about TRIM for SSDs installed in ...
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9answers
22k views

How many disks is too many in this RAID 5 configuration?

HP 2012i SAN, 7 disks in RAID 5 with 1 hot spare, took several days to expand the volume from 5 to 7 300GB SAS drives. Looking for suggestions about when and how I would determine that having 2 ...
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11answers
2k views

Is RAID5 more robust than RAID1

I am about to replace an old hardware RAID5 array with a Linux software RAID1 array. I was talking to a friend and he claimed that RAID5 was more robust than RAID1. His claim was that with RAID5, on ...
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7answers
4k views

Hot spare or extra parity drive in RAID array?

In a different question about configuring a RAID array, the author is building a RAID array with 8 drives. One answer suggests using 7 drives in RAID 5 with one left over as a hot spare. Since RAID 6 ...
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3answers
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Restoring an Amazon EBS RAID0 array from snapshots taken with ec2-consistent-snapshot

I've configured a new MySQL server on Amazon EC2 and decided to store my data on a EBS RAID0 Array. So far so good, and I've tested taking snapshots of those devices with ec2-consistent-snapshot, ...
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5answers
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Squid or Other HTTP Caches with SSD Cache Store?

I'm contemplating setting up a squid (or possibly varnish) cache on a system with SSD drives. The obvious benefit is that these systems have great READ speeds and I expect my hit ratios to be fairly ...
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21answers
5k views

When is RAID worth the trouble?

In our shop we're faithfully using RAID in all our workstations, probably just because that seems to be the way it ought to be done. I'm talking about workstations for scientific simulations, using ...
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7answers
31k views

What is a (raid-controller-) BBU for?

I am wondering what's the purpose of a BBU. My first understanding was, that it enables the cache to write the data to the disc during a power failure. But some specifications say that a BBU can hold ...
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2answers
10k views

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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2answers
5k views

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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5answers
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RAID 6 vs RAID 10? Which would you choose

My choice would be RAID 6 for a file server since you can lose two drives and it does not matter which set of two can die. From what I understand with RAID 10 you can lose two drives but if they ...
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6answers
3k views

Scaling databases with cheap SSD hard drives

I hope that many of you are working with high traffic database-driven websites, and chances are that your main scalability issues are in the database. I noticed a couple of things lately: Most large ...
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votes
4answers
4k views

RAID 1+0 vs RAID 0+1

I went with some advice I was given from someone I know to go with a RAID setup for this server I ordered. The specs are below. I plan on using this server to host multiple sites in a PHP/MySQL ...
6
votes
4answers
2k views

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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3answers
2k views

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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votes
4answers
2k views

Which RAID Level Should We Run For Virtual Machine Storage

We just ordered a server which we are going to use as storage for our virtual machine environment. Basically it will work as a block level storage device running iSCSI to each hypervisor. The server ...
3
votes
1answer
6k views

Proliant server will not accept new hard disks in RAID 1+0?

I have a HP ProLiant DL380 G5, I have two logical drives configured with RAID. I have one logical drive RAID 1+0 with two 72 gb 10k sas 1 port spare no 376597-001. I had one hard disk fail and ...
3
votes
2answers
3k views

Is it possible to use Linux as a Fibre Channel Raid Disk Box?

You probably all know the relatively simple RAID boxes exporting a bunch of SATA disks as one big drive via FC, SAS or iSCSI, like the HP StorageWorks MSA2000, Infortrends EonStore series or many ...
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votes
4answers
8k views

Windows file server performance tuning

I seek your opinion and tips/suggestions in optimizing the performance of a new Windows file server I'm building. I've inherited a Dell NF500 storage server (basically Dell 2950 with Windows 2k3 ...
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3answers
155 views

Hard disk / SSDs - detection and handling of errors - is silent data corruption reliably prevented?

When an error occurs on a drive, is it correct to assume that it will always be detected and reported to the OS (if software RAID such as mdadm) or RAID controller (if hardware RAID) as a failed read ...
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6answers
1k views

Should I 'run in' one disk of a new RAID 1 pair to decrease the chance of a similar failure time?

I'm setting up a RAID1 array of two new 4TB hard drives. I heard somewhere previously, that making a RAID1 array of new identical hard drives bought at the same time, increased the chance that they ...
18
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2answers
4k views

RAID-6: better to replace two dead drives at the same time, or one at a time?

We have a 16-drive RAID-6 that has three problem drives. Two are already dead, and the third is giving SMART warnings. (Nevermind how it got in such a bad state.) Obviously we want to replace the ...
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12answers
8k views

Should a backup server use RAID?

I was asked to set up a new backup server using Symantec Backup Exec that stores to hard disk instead of tape, because the backup size is outgrowing tape capacity. I was wondering does it really ...
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8answers
28k views

Guidelines for the maximum number of disks in a RAID set?

In any of the RAID levels that use striping, increasing the number of physical disks usually increases performance, but also increase the chance of any one disk in the set failing. I have this idea ...
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3answers
7k views

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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3answers
1k views

Four disks - RAID 10 or two mirrored pairs?

I have this discussion with developers quite often. The context is an application running in Linux that has a medium amount of disk I/O. The servers are HP ProLiant DL3x0 G6 with four disks of equal ...
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9answers
6k views

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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5answers
1k views

Need help with recovering RAID array

To make a long story short, I am responsible for a media server that has two RAID arrays (/dev/md0 and /dev/md2). I still have a ton to learn about software RAID and LVM, etc. We had a drive fail in ...
4
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1answer
4k views

How to over-provision an Intel SSD RAID Array via the Dell H700 PERC RAID Controller

I would like to set up a RAID10 array of 6 Intel SSD 320 SSDs, but over-provision them to enhance their performance and duration as per this PDF: ...
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2answers
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Odd mdadm output: --examine shows array state failed, --detail shows everything clean

The setup: 8 disks in a mdadm-managed RAID5 array (/dev/md0, made from /dev/sdc through /dev/sdj). One disk (/dev/sdh) is showing SMART errors (increasing pending sector count) so I'm looking to ...