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RAID stands for Redundant Array of Independent Disks.

RAID is data storage technology that allows multiple drives to be used together as a single virtual drive for reasons such as fault tolerance, reliability and performance.

There are several different levels of RAID that determine how the data is stored and the level of redundancy achieved across the drives.

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I have an existing RAID 5 4xTB Sata 3 in a hypervisor with 4x VMs.
Report sluggish behaviour from users.

HPDL360e Gen 8 Smart P420 1GB RAID.

I am considering breaking this into 2x RAID 1's to improve performance.
Any easy way to do this apart from:

a) copy data
b) kill array
c) new arrays
d) copy data


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We have a raid 5 cofiguration, and running out of space.  It is on a dell server r620 with perc h710 mini (embeded) controller.  If I were to replace one hard drive at a time to bigger size and let it rebuild .. will I be able to increase the size of the volume on the raid without having to backup and restore?

I have read contradictory information and I want to make sure, for example below is a link that gives step by step on how to achieve this.


I have an HP DL380p Gen8 server that has 2 Smary Array 420 controllers. Because of space issues I needed to move a pair of drives that were in a RAID1 set from slots 7 & 8 on the left side which was controlled by the 1st RAID card to slots 7 & 8 on the other drive cage that is controlled by the 2nd RAID card. However, after the drives were moved they showed as unassigned so, I shutdown the server moved the drives back to there original location of slots 7 & 8 which is on the 1st Array card now they are showing as unassigned there as well. Is there a way to recover the RAID set on those drives or is the RAID configuration gone?

What is the best RAID with 8 hard drives SAS 600GB, 15k tr/min 6GB/s (HP 517354-001) for virtualization server (VMware ESXi 6.5) ?
Basically we have multiple applications (MS Active Directory, Terminal Server, Oracle, basic file server,...) , one with intensive Oracle Database operations
There's two others array RAID5 SSD total 1TB and RAID1 300GB
Thank you.

Best Regards.
We have been getting these errors on Physical Disk 4 on our first virtual host:

There was an unrecoverable disk media error during the rebuild or recovery operation: Physical Disk 1:0:4 Controller 0, Connector 1

I did what it said to in the comments which was to swap it out with a new disk. However, after doing this and letting it rebuild, the same error repeats over and over again.

What can I do to stop this? All the lights show as green on the OpenManage console and in the rack itself.

This is a Dell PowerEdge R625 with 4 disks on RAID 5.
I have been running a Dell Precision 7600 for about 5 years for a small business. Recently, I had started to have some strange problems with Win7. Thought it might be HD failures (SAS), so did checkdsk and that crashed. Had PERC H710p, removed one of the HDs (storage), not boot, and was able to start up windows fine. Then replaced that HD, removed other storage HD, and all of a sudden PC can't find any of the HDs on startup.
Just bought a new PERC H710p in case that is the issue.
I'm looking for an independent consultant genius (not DELL tech support!) who can advise me/walk me through PERC setup, in particular at least I want to be able to copy data off of my old SAS drives.
Any advice?
i had a nas storage unit and the mother board on the unit died.

i wwas wondering if i purchase another nas storage without the drives will the new unit accept the drives and will ii be able to have access to the data on the drives.

in simple will the new box identify the raid5 and allow me to copy the data off
I have an HP Gen 9 server with 8 1.2T 10k sas disk (Local) and VMware installed on internal SD card, all disks are currently in RAID 10.
We're having an issues with our SQL server preformance and from what I've read and understand we need to separate the locations of the DB files from the log files, the problem is that even if I'll create a new drive it will still be on the same disk array so it's the same as putting them on the same drive.
My question is this :
Should I break the RAID and create new RAID 10 based on 4 drive each and then put the DB file with the OS on Data store 1 and create a new drive for logs / tempDB and put it on Data store 2 ?
Or do you have any other suggestions?
I can't replace the drive s to SSD because of the price is too high at the moment.
Any help will be appreciated.

Thanks in advance
How do I setup a LUN drive type for a single logical disk using a Raid 1, 1+0 on a HPE ProLiant DL360e Gen8?

I don't see the option in the ACU.   The server comes with 2 sas drives, and 6 sata drives.  I would like to add them all to the same logical disk.  Other servers in our organization are setup with 8 disks/Lun drive type Raid 1, 1+0 (ProLiant DL360P Gen8)

Is this possible on the ProLiant DL360e Gen8?  Is ORCA still available on this model?
Trying to install Server 2016 on a HP DL360e Gen 8 v 2.

Cannot boot with images. Intelligent Provisioning cannot see anything useful on the USB stick.

Tried using Rufus, NLite, Windwos 7 USB tool.

Also trying HP USB Key, but when I select the ISO, it says not supported.

I am using Action Packs ISOs downloaded. Also even tried putting RAID drivers on a custom boot using NLite as suggested by someone with the same problem.

I have an embedded RAID and also p420 1GB.
So I have made some logical drives on the P420.

Any ideas anyone... I am a little foxed at this stage.


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I have a Dell poweredge 110.  Server 2008 SBS. Raid 1 with two drives. Perc s100.
I thought that it should be able to boot with just one drive but it does not. I pulled up the configuration CTRL-R. It now says "Raid1, 499GB, Failed(R/W). However it does not show that the physical drive is bad.

I tried making a new drive a hot swap drive following these dialogs but I don't think a rebuild will even start with that virtual disk having failed.
Anything I can do?
Hi there,

We had a power cut and the server come back online and running. Completely fine, however the controller is showing a warning that it is queued for a rebuild however the disks are showing as ok and no failed drives, just the logical disk is ready for rebuild, I rebooted it again and it’s still showing the same, even the diagnostic reports are showing the logical disk as ok and the disks too, nothing obvious is standing out, really odd, it’s not running slower either.

Just can’t get my head around it, any advise would be greatly appreciated

Many Thanks,

Server 2012 stuck in boot loop. Server gets all the way to ctl-alt-dlt and then promptly reboots. Can boot into safe mode, and safe mode with networking. Server eventually boots and stays on. Inherited this system from someone else. System has a Raid 1 and both driver do the same thing.

Cleared windows update file, reset network connections, removed antivirus, removed logmein (sometimes logmein causes this.)
We have a DELL PE R630 server with PERC H730P RAID controller. It has a RAID 1 VD containing Server 2012 R2 Standard. It has 2 more RAID 5 Virtual Drives containing data. Can an additional Virtual Drive be added with a group of new physical hard drives?
    I have a 3 Drive RAID 5 on a Server and so far every Backup Software that we have tried has failed. We have run a program called HDTune Hard Disk Utility and the results showed 1 bad Block. Is their any way (software) to repair this or mark this block so that the backup software can bypass this?


I’ve had two PC’s have an issue where I get the error
From the RAID controller:

RAID -foreign configuration found all drives lost.

The 1st time, not being familiar with the error. I gave the user a new PC, thinking the HD failed.

The 2nd time, I imported the foreign configuration and all seems well.

So my basic question is, does the error:

RAID -foreign configuration found-all drives gone

Mean the drives or controller is failing or unreliable or something else?

Any insight into this issue would be greatly appreciated

Thank you
I have a Windows 8 PC, where the D Drive is a RAID 1 array, using the onboard RAID.  About a week ago, I updated the BIOS, which inadvertently switched my ATA mode from RAID to AHCI (hence breaking RAID).  I didn't notice right away since Windows did not assigned a drive letter to the other disk.  I attributed the boot up failures to the UEFI update, and Windows was able to self correct the problem.

Once I found the problem, I went into the UEFI, changed ATA back to RAID.  The Intel management software showed that the disks were syncing, but it apparently caused corruption in the NTFS partition.  I have lost about a week's worth of data in my Access file, and my backup software (iDrive), has not been backing up my data as I thought it was.  My last successful backup of my Access database was about 2 weeks ago.

Is there anyway of recovering my Access database?  I tried using recuva, but it was run against the RAID array, which showed no recently deleted files.  I might send the hard drives to one of those hard drive recovery companies, but am hoping that there is a cheaper solution available.

Any ideas what I can do to resolve this issue?
The Adaptec Raid Controller Stripes failed for some reason, the controller details are given below. It is a live server, please give any suggestions to fix the problem without data loss. Restoring data on new disk/server is highly complicated.

Controller Model                  : Adaptec 5405

Logical device number 0
   Logical device name                      : DATA
   RAID level                               : 5
   Status of logical device                 : Optimal
   Size                                     : 571382 MB
   Stripe-unit size                         : 256 KB
   Read-cache mode                          : Enabled
   MaxIQ preferred cache setting            : Disabled
   MaxIQ cache setting                      : Disabled
   Write-cache mode                         : Enabled (write-back)
   Write-cache setting                      : Enabled (write-back)
   Partitioned                              : Yes
   Protected by Hot-Spare                   : No
   Bootable                                 : Yes
   Failed stripes                           : Yes
   Power settings                           : Disabled
I guys,
I got a windows 10 computer. Got 2 hard disks, running with raid 1

Not sure what happened, but today after weekend, windows not booting and the HDD light is red
- checked raid configuration it shows- raid 1 status rebuilding

Should I just leave it rebuilding in the rapid storage technology page, till the status comes as Normal ?? Because if I exit out of that page, it keeps trying to boot into windows and saying could not find harddisk

And how do I find which hardidisk is faulty in 2 harddisk ?
I tried removing one hdd- raid status showed as degraded
Tried removing second harddisk with first harddisk inside - came as failed

Does it mean the first harddisk is failed ?? Or any other way to find which harddisk failed or is it just raid problem ??
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Hi I wanted to use software mirroring to mirror a Windows 10 drive, system actually.  I'm going to use like a 250 ssd, don't think that matters.

I know the older version of windows didn't let you software mirror unless you had Ultimate, or maybee Pro.  

Question, Windows 10, what version comes with the mirroring capability.
I have a server 2008 r2 that has a software raid 5 with 4 drives.  I have one drive failing and need to replace it.  Its not in a failed state yet but senses it is failing.  I have seen several horror stories on the process and and want to ensure I get it right the first time.  What is the correct process to do this?  I do not have a extra drive bay so I will have to pull and swap.  Do I need to do this with the server off or do a hot swap?

Again, I don't want to get in to the situation where it is not recoverable and need to know the correct steps to take.

Thanks in advance.

After I lost a RAID5 of three disks, I added a new RAID1 of two disk to reinstall vSphere ESXi 6.5 U2 (previous was VMware-ESXi-6.5.0-4564106-Fujitsu-v400-1)
I had another RAID1 with a VMFS datastore and also a RAID0 (Don't be rude with me...)
During installation of vSphere ESXi 6.5 it didn't recognized the VMFS datastore unlike the RAID0.
I don't think I broken the  RAID1. I read this : https://kb.vmware.com/s/article/2148265
But I don't think it apply because I installed back the previous 6.5 version (4564106-Fujitsu) and a 6.0 version too.
The RAID adapter is a LSI MR9240-4i
I used some tools to check one of the disk of the RAID1 and theses tools can locate the VMFS datastore and the files I'm looking for (a vmdk) but theses tools are not free when it's time to recover...
- https://www.diskinternals.com/vmfs-recovery/
- http://www.vmxdb.com/soft/81.html

I also tried to use the Open Source VMFS Driver but it can't see the VMFS partition when I run : java -jar fvmfs.jar  \\.\PhysicalDrive1 info

I have a backup but I would like to get some files only present on the current RAID1.

I did not yet tried to install linux (instead ESXi) on the server with vfms-tools to check if I see the VMFS partition...
Is there a quick way, free tools, that let me read this partition en extract the VMDK I'm looking for?

Thank you for any help.
I recently got an older server. 6gb RAM, 1x2tb RAID array. 4 core CPU. Literally an old file server.

I upgraded their server and took this one.

It originally came with Server 2008, but I was unable to recover the key (they wiped the drives and it didn't have a sticker on it.

I was wondering of a linux OS with a web-based GUI. I have used Webmin in the past, and I like it, but it doesn't seem to be updated very often.

I want to know if there are any similar to you Webmin that you like to use. I don't really want to hang out in my office staring at a screen and I ain't great with terminal commands (through SSH). I like the module options like in Webmin. I have also tried Cockpit project, but it doesn't have much on it. And ClearOS is not that easy to use when setting up samba share. Amahi, I have the same issues.

What are your recommendations??
I purchased a "YK838 - RAID Controller PCI-E SAS 2-Channel SAS6/IR PowerEdge R510 by Dell."

The Amazon URL of where I purchased this adapter from is here.

What kind of cable adapters will I need that will allow me to connect two Serial Attached SCSI (SAS) hard drives to this PCI controller card?
I have two disks in Predictive Failure on a Dell Poweredge C2100 (Using Open Manage 8.2). We got new SAS drives to hot swap in. I started with the Global Hot Swap (in Predictive Failure) and replaced it with the new drive.

At first it gave the Green Check Mark, "ready" and i could assign it to the Global Hot Swap in the Physical Disks Section but got the attached Caution message. It still allowed me to assign it as a hot swap but was not being recognized as a virtual Disk in the Raid Array. Prior to swapping we could see disk 12 in it's own "Global Hot Swap" section under the other 11 disks in the array.

When i tried the "Create Virtual Disk" and "Assign/Unassign Global Hot Swap" options in Virtual Disks it would not show up as an disk i could select.

When i went back to the "Physical Disks" section the new drive is now showing as "Foreign" and i don't see an option to reconfigure it.

Help is very appreciated.


RAID stands for Redundant Array of Independent Disks.

RAID is data storage technology that allows multiple drives to be used together as a single virtual drive for reasons such as fault tolerance, reliability and performance.

There are several different levels of RAID that determine how the data is stored and the level of redundancy achieved across the drives.