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 older server Dell Power Vault NF 500.  It was running Windows 2003 storage server.  A week back the drive holding the OS failed.  There are two drives on one controller (C: drive)  and 3 drives on another controller.  The data is held on an array (Raid5) with three drives.  I simply want to get the data off the array (Raid 5) drive and onto a backup disk. I am guessing the two drives holding the OS were a RAID 0. How do I go about getting the server back up and not risk the drive with the data?  I can stick another drive in there and install an OS on the drive but will it see the data drive after?   Will the install leave the RAID 5 alone?

I have never had to do this in the past and I cannot afford to make a mistake.  I would love to get some advice and queue up a conversation with someone who has experienced this before.

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We have a PowerEdge R610 using PERC 6/i Integrated (Embedded) controller. There is a RAID 1 and a RAID 5 (3 disk). One of the disks failed on the RAID 5, So we purchased additional 300GB disks (1 to replace the defunct, the second to introduce as a hot spare).

The first disk was added successfully into the RAID 5 array. The second disk was inserted, and after trying to add it as a global hot spare, the status changed to 'foreign'. I have been unable to change the status from 'foreign'.

I have attached some screenshots to assist.
Physical Disk StatusVirtual DisksStorage Dashboard
Can anyone assist with this please?

vcenter server 2008 throwing event ID 1, onload():cannt find any HBA or networking controller also no raid controllers found. wondering if anybody has encountered this before.
Hi Folks,

I'm a Server Admin albeit for a small company with a Single Gen 9 HP Prolinient Server that is Virtualized.

The storage is RAID 10 (8 x 1.2TB Drives).

Am running low on space so need to increase.. want to add another (4 x 1.2TB Drives) giving me an extra approx 4TB of space.

Looks like this is all I need to do? Start an Expand and once started I can boot up server? Do it on a Friday night probably let it go over the weekend.
VMware ESXI 6.0.0 hangs when loading vpxa start.  I little background.  This customer had a problem in which some water got into the back of the server and killed the motherboard.  So I replaced the motherboard with the same model, it is a PowerEdge 610.  I swapped in the RAID controller, memory, and processors.  The system now boots up, sees all the memory and starts to load VMware.  However when it gets to vpxa start it just hangs.  I can ping the system but using a browser, nothing comes up.  Trying to login via the client, it times out.  I also tried SSH and it refuses the connection.  This is a small office and this is the only VMware system installed.  I have vCenter running as an appliance under this unit so I do not think it is loading.

I would like to get the server VM files that was running on this unit copied off if nothing else.  I can then reinstall VMware and reload it.  Any ideas on how to get into this system to try and fix it?
I received a E1810 Hard Drive 4 Fault. Review & Clear SEL on my Power Edge T610 server hardware display. This server is out of warranty, and is no longer support.

I am also receiving the following pop ups generated by Dell Open Manager:

         Predictive Failure Report: Physical Disk 0:0:2 Controller 0, Connect 0

      Predictive Failure Report: Physical Disk 1:0:4 Controller 0, Connect 0

      Command Time Out on physical disk: Physical Disk 1:0:4 Controller 0, Connector 1

I have 2 146 Seagate SAS drives configured in  a RAID 1 housing the OS - Windows Server 2008 R2, and 4 configured in a RAID 10 for data. It is the RAID 10 that is showing the failed/predictive fail drive.

I'm feeling all I really need to do is pull the bad drive (hot swap-able) and insert a new Seagate Cheeta SAS drive (same drive as original) to start an auto RAID rebuild. But, nothing ever goes that easy.  I would feel a lot more secure in my pursuit if I had expert advice.

Should I be safe and shut down to change the bad drive, then enter the RAID interface? Should I shut down, replace the drive-boot, then attempt the build from within the Dell Open Manger? Or, can I just hot swap the drive and let the existing RAID perform it's own rebuild?
Hi I have Dell t410 with 3 degraded raid 5 drives and their continually rebuilding.  After reading a few threads i thought i'd ask for some assistance.
Previously I swapped all 3 drives and was able to bring them to an online status. I've now installed new OS which is fine but the drives are continually rebuilding, taking resources and i'm not sure if the raid card is faulty or there's settings to reconfigure?
Can you help please, thanks Steve.
The user does video editing with Adobe Premiere on an iMac with Thunderbolt.
They are looking for a well-priced 16TB RAID 5

Would the following configuration be good?
  • Drobo 5Dt: 5-Drive Direct Attached Storage (DAS) Array with mSATA SSD acceleration - USB 3 and Thunderbolt 2 ports (Empty) DRDR5A21-T  (3.5 stars on Amazon)
  • Seagate 4TB IronWolf NAS SATA 6Gb/s NCQ 64MB Cache 3.5-Inch Internal Hard Drive (ST4000VN008)  (5 of these)

The cost looks to be about $1100.00

Is there another manufacturer that we should look at?
Any problems with Drobo?

I have a windows server 2012 r2 that won't boot that had a raid disk failure earlier this morning (7/30). The server rebooted and now it is attempting to install updates. It gets to roughly 50% and then fails with the error Error C0190003. Which states that there are so many update operations being processed that the transaction log becomes full and can't finish updating. The workaround is to change the transaction log limit in CMD, but the server won't boot into safemode with CMD.  I tried Last Known Good Configuration as well and it attempted to install the updates again and failed.
I have a client with a windows 2012 server r2 with data drive that fragmented with 1.8 terabytes of data. It's taking forever to defrag, i mean days. This is very nice server with raid 5 (LSI card with 6gbs support and all shows optimal in the web gui) Two 8 core Zeon CPU's, 64 gigs of ram. it has has 6 1 terabyte seagate serial attached scsi drives in it. it has been running fine for a long time. Now it's not. when I noticed the drive was fragmented at 82 percent. Has anyone got any ideas to share?
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Hello, I'm looking for a good local backup solution. I'm considering either direct attached storage or a NAS device. I'm looking for something that has the ability to utilize NTFS permissions using my existing AD user/security accounts so that various users within our domain would not be able to access this data without being given specific access. Can anyone recommend something preferably in the "under $500" range with around 4TB of usable space? I'm not real concerned with RAID configurations as this would just be a local redundant backup (already backing up to Carbonite).
Thank you!

I am working on  a HP ProLiant 580 Gen9(rhel 6 is the loaded os) I am trying to eject a SAS SSD safely while using the ssacli command line utility. I have the single drive configured in a RAID 0 Array w/encryption. I am basically just trying to unmount the disk while the server is turned on so that I dont receive any health errors and the do not eject light turn off.

Is there any command to be able to achieve this through ssacli
Hi Guys, we are a small business we are trying to implement a file server using windows server 2016, we can't afford a h/w raid for now to have a proper NAS. so i'm researching the alternative. so for the data experts out there what file storage NAS can we use in a windows server 2016 AD environment. so far we are comparing unRaid, FreeNas, stablebit drivepool and windows native RAID.
I have an HP DL 320e that won't get past post. After a recent planned shutdown, it just won't restart. If you push the power button, the system attempts to start and then stops right away and the red health light blinks quite fast.

We read some support articles on HPE's website and attempted some fixes such as swapping out the power supply, the power cables, trying a different power outlet, etc and the power supply doesn't seem to be the issue.

We have another server that is the exactly the same and with the same Raid setup but is performing a non-critical task. The Faulty server has a Raid 1 setup with hard drives in Bay 2 and 3. The working identical server has a Raid 1 setup with hard drives in Bay 1 and 2

My question is can I just swap the hard drives between the two servers since they have the exact same Raid 1 setup and are the exact same server?  I don't think its that easy but wanted to check before attempting my next step of swapping out the motherboard.
We have to serve 50,000,000,000 requests per day, our app can handle that, but we're not sure if our database skills are there to pick this up. We have a database server with 256gb of ram and 512GB SSD RAID using percona edition. Some of the data needs to stay on the database for 30 days, the transaction table where all requests are stored. what approach do we need to scale this horizontally? each endpoint requests runs about 4 queries...
HP ProLiant ML350 Gen9 Raid issue.


Windwos 2012 R2 Server
Was hot swapping some drives to determine if bay was issue or one of the SSD's was the issue. Something glitched and there was an HP based BlueScreen that said something about there was a problem and we need to restart, but we are collecting some data first. After reboot the server cannot find bootable device.

The hard drives are detected in the raid. The following screens show the issues when in the HP RAID Controller screens after choosing F11 Boot settings:
RAID Controller Screen 1
RAID Controller Screen 2RAID Controller Screen 3
This last screen is my main question. If I cleick REPAIR. Accept data loss and re-enable logical drives(s) how much data are we talking about losing? Everything or just the last sync fo the RAID drives.
RAID Controller Screen 4
If this option will lose everything then is there a way this raid array/logical drive can be repaired without loss of the boot OS?


Hello Experts,

I need to manage a partition in Proxmox.

I have Proxmox working with a SD drive 500 Gigabits.

I added a RAID 1 12 Terabytes disk volume for storage. I need to manage this RAID 1 volume and make it available for the VMs.  I need to partition the Disk and make it available for the VMs.

I am reading about a BIOS change for the VMs and also LVM management.

Not able to make sense of my Google findings:

In order to properly emulate a computer, QEMU needs to use a firmware. By default QEMU uses SeaBIOS for this, which is an open-source, x86 BIOS implementation. SeaBIOS is a good choice for most standard setups.

There are, however, some scenarios in which a BIOS is not a good firmware to boot from, e.g. if you want to do VGA passthrough. [6] In such cases, you should rather use OVMF, which is an open-source UEFI implementation. [7]

If you want to use OVMF, there are several things to consider:

In order to save things like the boot order, there needs to be an EFI Disk. This disk will be included in backups and snapshots, and there can only be one.

You can create such a disk with the following command:

qm set <vmid> -efidisk0 <storage>:1,format=<format>
Where <storage> is the storage where you want to have the disk, and <format> is a format which the storage supports. Alternatively, you can create such a disk through the web interface with Add → EFI Disk in the hardware section of a VM.

When using OVMF with a …
We have two new HP servers (HP ProLiant DL360 G9) with 3 SSD (Intel SSD DC 240GB S4600 series ) drives in each. I will be setting them up as Domain Controllers (to run 2016 standard). Normally our file servers, etc. those with many drives were setup using RAID 5 and our Domain Controllers with simple mirroring. However, as RAID 5 is now outdated and we only have 3 drives I thought of using RAID 1e since that seems to be the best and recommended option based on my reading (e.g., but could someone who does this a lot (we only build 3-4 servers a year and many are virtual) confirm this or make alternative suggestions with explanations. As always greatly appreciate expert insights and feedback.
Hi, trying to replace a failed disk on a Dell Perc S110.  When I try to hit insert to assign the global hot spare as I have done in the past I get the following message/errro.

Not selectable: Disk is in use by a virtual disk

The two hard drives that are still OK are 500 gig Dell drives, I tried a 1 and a 2 T Toshiba, same error.

Thanks all
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Hi, I'm looking for a decent RAID card for around 200 or so.  I wanted a Perc controller, but not stuck on it.  I wanted to run RAID 5 with 3 drives and a 4th as a spare.  I just want it to have sata drives, I don't need the SAS connections, and I really don't want a battery, just something better than the onboard connections and software raid.

Thanks a ton all.
Hi, we have an HP ML350 G9 server with a raid 5 array, now i am adding 2 new SSD drives and wanted to build a Raid 1 array additional. Does anyone have steps for this so i dont screw it up?

Hi. I have a question regarding a predictive failure on a RAID 1 drive on a Dell Poweredge T620. The specifics are that the T620 hosts 2 server VMs, and has a RAID 1 and RAID 5 array, A drive in RAID 1 indicated a predictive failure, and I'm wondering the viability of adding a new drive (NOT the same model as this server is out of warranty), that is a 600GB drive replacing this failing 300GB drive. Is it possible to plug in the new drive, initilize it via the BIOS, then set it up as a hot spare so that the array rebuilds itself using the new drive? If this is possible, do I have to manually use Dell Openmanage to tell the old drive to turn off (it seems to have options for that), or will it automatically rebuild the array upon detecting the failing drive? Thanks.

The main concern is if using a different drive is possible. Is using a larger one okay? I want to hopefully minimize downtime.
Hello, All.

Before I go any further with the RAID 5 configuration that I currently have set up.

What is the best array to run for a web server running?
IIS, SQL Server, Mail Server, etc...

I currently have 4 - 500GB drives in the ARRAY.

My RAID card gives me these options.

RAID 10,
RAID 50,

I have another server that will be brought into the network by the end of summer, and another server by Christmas.
So, whatever information I get here from this thread, will most likely be used across all servers.

Suggestions are greatly appreciated.
I am still somewhat new to Virtualization and I am currently in the process of upgrading/expanding my VM server farm. I was going through some documents and in of the documents it mentions that I should have a separate disk array for each virtual machine on a multiple virtual machine system.

My question is what do they mean? I have a 6 disk server and would like it to host 3 VM's. From how I read the statement above I should configure server into 3 RAID 1 configurations where normally I would configure either a RAID 5 or 10 then split the array into however many disks I need for the 3 VM's.

What is the correct way? Right now I have all of my VM servers configured as RAID 5 the chop up the array into drives for the VM machines
Hello, All.

OK, I have the following.
VMWare 6.5 Update 1 (Free version)

Adaptec RAID 6805T

I have it configured for a 4 drive RAID 5.
However, it is not showing up inside of ESXi.

I found this driver.
Adaptec RAID Driver v1.2.1-52040 for VMware

However, the driver is for versions of VMware 5, 5.5, and 6.0
I have 6.5 update 1

Also, if this driver will work with 6.5 u1
How would you install it into the FREE Version of VMWare?

I also found this information as well.
I just want to make sure that this is going to work before I attempt it.
How to install 3rd Party RAID controller drivers in VMware ESXi 6.0

I would like so input on this before I attempt to do this.
As this is on a production system, and I prefer not to mess anything up.



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.