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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Had a glitch this morning with our raid 5 array.  I resynced the array and said all was good but now there are two exact array using the same drive.  I fear if I delete one it will delete both.  Its an adaptec drive array controller.  I have vmware on the server and its not seeing the config to boot correctly because of the ghosted array.  Any ideas.
Hi. I have an older HP ProLiant server and have a quick question about RAID.
The server has 8 hard drives.
The first 2 were used for a RAID1 setup and that's where the OS was installed (Server 2008 R2).
The other 6 drives were setup in a RAID10 config and housed a COPY of the company's data.
I decided to replace the first 2 drives with SSDs and was thinking that the other 6 drives would still be accessible after the OS was reinstalled on the 2 x SSDs.
I noticed when I initially booted into the RAID setup, I saw a message stating that some drives and configs were removed and such.
It's not a HUGE deal to recreate the RAID10 config on the other 6 drives and copy all of the company data again, but it is very time-consuming.
Just wondering if I have any options before I recreate the RAID10 config and copy everything all over again.
Thanks in advance.
Have a Lenovo TS430 server with LSI Megaraid controller and 3x 450 GB 15K SAS drives in RAID-5. Server has been working for over 5 yrs and recently had started to run out of space on the HD volume. I did a cleanup and removed lot of files recently. Ran a De-frag to improve fragmentation. Later that night, it failed at maybe when defrag was going on.
Found that 2 of the 3 SAS drives were not recognized by the RAID controller as part of the Boot array. There we two disks showing up as "Configured, Bad". Was able to "import" the "Unconfigured, Bad" disks into the array and brought them "Online" using the WebBios for the LSI controller. Mde sure the array was set as the boot device in the RAID menu.

Optimistically, tried to boot into Windows Server 2008R2 installed on the server.. Boot Failed with Windows saying boot device cannot be accessed. Went back into the LSI WEbBios, and now it reports that one of the 2 drives that I imported is being "rebuilt" into the array. Hoping that perhaps that will restore booting. However, since this is a hardware raid-5, cannot understand why Windows is not booting even if array is being rebuilt.  Windows boot screen suggests using Windows Server boot CD to do a boot repair. Waiting for rebuild to complete before I try going further.

Any advice?  Thanks in advance. This has been a nightmare.

System is a PowerEdge R710.with PERC H700 integrated controller.  The virtual drive in question is RAID 5 with 3 drives. I have been monitoring controller logs weekly, and running consistency check for the past 3 months with 0 issues.  Suddenly yesterday, OMSA is showing 1 drive as predictive failure.  I went through logs and see a bunch of unexpected sense logs many of them stating "corrected medium error", but I do not see any unrecoverable errors.  I went onsite, offlined drive, then inserted new Dell branded drive.  Rebuild completed, but the new drive is also reporting as predictive failure.  I went through logs again, and notice many more unexpected sense logs during rebuild process.  I then ran consistency check, which again had many unexpected sense logs.  Drive is still in predicted failure state, so I replaced drive again with a new drive.  This time, after rebuild drive was not showing predictive failure.  Just to be sure, I ran another consistency check, which put same drive in predictive failure state again.  There are again a bunch of unexpected sense logs many of them stating "corrected medium error".  I am unsure how to proceed.

The firmware for controller, drives, & BIOS are all up to date, but IDRAC6 & Lifecycle are out of date.  IDRAC6 is at 1.92.00 (build 5) and Lifecycle is at

Please let me know your thoughts.  If you recommend updating IDRAC6 & Lifecycle, please let me know where to find updates and steps for updating.  I am a …
I am ordering a new server.  It will be Win 2016 and only be used as a DC.  It will have three drives.

My question is should it be Raid 0 or Raid 1?
What is the best config for VMWare 6.7 for the following hardware: HP DL380 gen 10, 2 processors (8 core) with 64 GB memory each, 6 x 960 GB SSD, 2 x 4 ports networkcard

I am talking about :

1) Which raid config (Windows servers and some Linux machines will run on as a guest, 10 in total)
2) Network setup (teaming or not),
3) How to get the best performance out of this hardware config
I have an issue of requiring more space on my primary partition.  I have a Dell 410T, 4 x 300GB 10K RPM SAS 6Gbps 2.5in Hot=Plug Hard Drive, PERC H700 Adapter RAID Controller 512 MB, RAID 5, Total of 837 GB 40 GB Primary partition on C: and 794 GB on D (525 GB Free). I would like to shrink D and expand C by 60 GB.  The server is running preinstalled software.  Is there a way I can do this without destroying the existing disk structure?
Hi, I was going to build server with 3 2 Terrible drives and put them in RAID 5 to get about 4 T of storage and fault tolerance.  

I remember allot of techs here didn't like RAID 5 due to the amout of time it takes to rebuild and that another drive can fail in that time.  Is that still true, or was it ever with SSD's?

The controller I'm using is a PERC H730P

Thanks a ton guys
I have dell t620 with a perc h710. It is configured raid five with 6 930g sas drives with a capacity of 4.5t.

A few days ago i saw on a reboot the there was a foreign config on the drives. as the os was booting properly i cleared the foreign config.

After hat I noticed that the virtual drive is in a degraded status. Drives 1-5 are online but drive 0  appears unassigned with a status of "ready". the only option the controller gives me is to set it up as a hot spare. I tried that and it set up that way but it wont integrate to the basic drive. How do I get it to reintegrate?


I need to replace a six year old Dell Poweredge T620 server.  I was thinking about replacing it with another Poweredge T630, with this CPU:  Intel® Xeon® E5-2630 v4 2.2GHz,25M Cache,8.0 GT/s QPI,Turbo,HT,10C/20T (85W) Max Mem 2133MHz.  I want to use Hyper-V but I'm not sure if I should use RAID or if there really is a big enough performance advantage for the extra cost.  I was thinking about going RAID10 using the PERC H730 RAID Controller with 1GB NV Cache but is that a good idea to have the VHDX and host all on the same RAID10?

Would there be performance problems if I just had two stand alone SSDs?  One would have the host Windows Server 2019 and the VMs would be on the second SSD.  I understand that the speed difference between stand along drives and RAID10 (with 4 drives) is 4 times faster the read and 2 times the write.  But with the SSDs being so fast now, is it necessary to go with RAID10 for a small office?  I will be running an Active Directory/Application VM and a Remote Desktop VM.  There are a total of 15 users and 5 of them will occasional work on the Remote Desktop VM.  Thanks in advance for any and all suggestions, recommendations and criticisms!
What's the difference between a Data Center Internal Hard Drive vs a Network Attached Storage Internal Hard Drive? Can a Data Center Internal Hard Drive(s) be used in RAID? Out of curiosity, what brand hard drive(s) does Google in use their Data Center?
Going to set up a server for a small company...6 employees...
Poweredge T130....two 4Tb HD's in RAID 1...
Server 2016 Essentials...
This will be my first time on a server with RAID1...

Whenever I have set up RAID1 in the past on a working PC....I've done a software RAID with the OS...

But on a small you suggest a hardware RAID...???

Is there any real difference...???

Recommend a RAID card...???

Thanks in advance...
Hey guys,

we have a strange problem. We built a RAID 5 with 4 SSDs, fast initialized it and installed a Windows Server 2012 R2. The Serverview Raid Manager shows a INITIALIZED STATUS - NOT INITIALIZED of the Virtual Disk

The RAID controller is a PRAID CP400i Megaraid

How big is the problem?


I have the following error message on my Hyper-V host event log.Just wanted to find out this is something to do with the Raid driver ?

An error was detected on device \Device\Harddisk2\DR2 during a paging operation.Event ID 51
Hi I got an Asus computer new that supports raid, I was trying to setup two ssd 2 Teribite drives in mirrored mode.  I go to the EZ Tuning Wizard, then switch from OC to RAID, it allows me to choose SATA after that I get no avalable disk drives.  They are in and the bios sees them, just not in the RAID menu.

Thanks a ton.
Dell R710 - PERC H700 Integrated Driver.

We formatted this server for the purpose of converting it into a Domain Controller for one of our other locations, (replacing a server that died) running Windows 2008 Server R2.

Once we installed Dell OpenManage it kept indicating that the current version ( is older that the required version ( of the controller, see image.

I already have the version installed as you can see from the image but OpenManage isn't seeing.
I have Proliant DL360 Gen 9 with Smart Array P440ar.  I installed a 4th 300gb hard drive into an existing Raid 5 array.  I don't know how or why but my array switched to Raid 6 (ADG).  At least i think it did because I believe I originally set it with Raid 5. My question is can i downgrade it back to Raid 5 without losing data in the array??
Storagepools vs Raid 10.
Hi. We are setting up a physical server (not running Hyper-V) to act as a Domain controller and a SQL server.
Plan is to use 8 x 600GB drives (SAS) sat up in Raid 10 (using onboard Raid controller - HP ML 350 Gen10 server)
Divide in 2 partitions C: for Win 2016 and D: for SQL data.

Not familiar with storagepools.
Is an option to use 2 disks in a mirror (created on raid controller and create a Storage Pool in File manager after windows is installed.
Looking for max r\w but also safety in case of disks crashing.

This setup may also be used for single Hyper-V host as well?

Happy for any suggestions
New Dell Precision 7820 Tower.  It came with the LSI 9440-8i Raid Controller.  I need to downgrade the operating system on this computer to Windows 8.1 Pro to accommodate a software package.  Since Windows does not recognize the controller card, I am struggling to find the driver in the format which the Window 8.1 will install.  Dell has the appropriate driver, but even "unpacked" it consists of .exe files.  

Does anyone have a way around this issue.

Thanks for your help in advance.
I need to add more space to one of our new customers pre existing server.
Its really a regular pc that is running server software.

the mainboard is a Gigabyte z77x-ud5h. i7-2600k processor.

right now they have 2 256 GB SSD. and they have them setup for raid 1 using intel rapid storage technology version

We need to add more space but I am not familiar with this kind of raid. I'm used to HP ProLiant servers and dell. that have their own software.

We are going to put in 2 500 GB DHH to make more space but I'm not sure how if this software support 2 separate arrays.
that way I don't have to reinstall the OS>

When I go into intel RST  there is no option to add anything. I don't have the new drives hooked up yet. I was just checking where to add or if you can add more than one array.
In a Dell T430, we are going to replace the existing PERC H330 RAID controller with a PERC H730 RAID controller.   We have been advised that "all we need to do" is remove the existing controller, install the new one, and "import the configuration."

Can we use Dell's OpenManage softwaere to export the configuration (i.e. to a flash drive), then after installing the new controller, import the configuration?

Suggestions on how to proceed?

Thank you...
I have a dell PowerEdge R610 physical server (W/Perc H700 Raid Controller) that is setup as an esxi 6.0 host. The 3 internal disks are setup in raid 0 for some reason and i want to know if i could swap the prefailed drive with a new one (which i already know will kill the raid 0 array configuration) will i be able to rebuild the raid array to be raid 1 with Dell EMC OpenManage Server Administrator (OMSA) without shutting down server? The hard drives are not dell certified disks.
Dear Experts,

This server has two HDDs of 300GB each and a smart array controller P410i installed with VMware which our customer give to us.

The issue now is we want to clear the data from the 2x HDDs.

1. I have tried going into the array configuration page and change and remove the RAID.
2. Boot using Windows 20121 R2 DVD installer
3. Removed both HDDs and power on server
4. Used a USB thumb drive as an installer
5. Connect a USB DVD drive to run WIndows 2012 R2 installer
6. I am unable to use iLO2 as the virtual media license is required

All the above I tried and it does not work, the server just boots and goes back and run VMware.

I have ran out of ideas.
server 2012 startup faliure

due a power problem my server wont start no more
any advice
may be the raid card?
please any advice is helpfull!
Lenovo TS440 Sever with what appears to be failed drive!

Okay, got a call and was asked to troubleshoot a server, lenovo ts440 4 drive bay server. It has 3 drives, the data resides in a raid one array with 2 4tb drives and I am assuming is okay. The other drive is a 500gb Seagate that held the OS Server 2016. I can get to boot screen and after that nothing, just hangs, disk repair yielded no help with same result. So question is, if I replace this drive and reinstall the OS will I lose the data on the raid one array or will windows see it already formatted with data intact and again I am assuming that array is okay, the raid controller shows it to be functioning correctly.

Thanks in advance and before you lecture me on setting an OS on a single drive with raid available, I didn't do it, I've just been asked to help.. Cheers.

Another thing, They have a clean backup that is a day old, backup is only system data files, not a system backup


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.