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 old PowerEdge 1900 that has a Perc 5/i in it.  I go into the configuration utility and select RAID5 for setup.  I have 4 750gb hard drives, so it comes out to 2.2 tb, or close to it.  I initialize the disk and when that is done I step through the rest of the process and on the last page I select "APPLY" then CTRL+ALT+DEL to reboot.  Upon rebooting there is a message that says "All of the disks from your previous configuration are gone".  It tells me that there are 0 logical drives on the host adapter, and obviously, 0 logical drives handled by BIOS.  What is the issue?
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Hello -

I have a DELL PE R710 and it currently has 6 HARD DRIVE, 146G, SERIAL ATTACHED SCSI, DU, 15K, 3.5, SEAGATE, HUR and a PERC H700 Integrated RAID Cont roller, 512MB Cache, x6. I would like to use two Samsung SSD 850 EVO (Model: 75E120) as a RAID 1 (OS), and 4 more drives as a RAID 10 (DATA FTP). My question is if I replace my existing drives, what hardware will I need to convert the server drive bays and will this work with my existing PERC? Will it recognize new drive and speed capabilities?

Thank you so much!

I have a HP Gen6 server with a P410i controller. ESXi is giving me the following warning:

We also notice the performance of our server is slower and the backups seem to often fail.

I could not find any errors in the ILO. Does this mean I just need to replace the battery of the controller?
I have a synology with 2 4TB HD raid 1 and 1TB of data (as per the data analyzer tool on the synology, and ThreeSize) but is the disk overview it shows 98% full

Please advice

bought new LARGE SSD and after adding new LARGE SSD Disk to windows 10, I can't expand the volume from disk administrator.

I use LSI raid card and I follow the support staff's instruction on expanding the SSD volumn to the level I want, and then in Windows 10 disk administrator, I see the new volume but it seems i can't make use of it?

anything I can do to make the volume circled become one volumn ?

tks. you can see that there are option for c:\, marke partition as active, should I choose that?

and I checked this one and I am not sure if I should use this:
My SCO Unix RAID 5 server have 3 HDD. Today 1st and 2nd HDD failed only 3rd HDD showing ONLINE. Is there any chance of data recovery if i install new HDD in 1 and rebuild and then the 2nd HDD and rebuild.
Is there any chance of data recovery.
I typically configured my spinning hard drives for the OS and Data files as Raid 1. If something happened then I just swapped out the drive and kept working.

When I got the SSD drive for the OS I could only afford the one drive. Now the prices have come down and I was thinking of again using Raid 1, for availability.

Talking with Samsung Tech Support they said that it would work but that they don't recommend it due to the fact that it would shorten the life of the SSD.

Having just had the drive fail and while waiting for the replacement I am thinking of getting my system up with a new SSD and when the replacement ships putting it in a Raid 1 set.



We are setting up a new network, we have the following:
2 Servers XEON (1 8gb RAM and 1 32 G RAM), both have RAID and 3 x 4Tb drives.
2 NAS Boxes (both have 4 x 3Tb drives and RAID.
2 x 24port Gigabyte switches
Plan to use Windows server 2016 on both
There are 26 workstations that will be connected (all Windows 7 32 bit) due to the nature of the applications they will be running (the applications might work with Windows 10 32bit, but needs more testing to ensure everything would work. Yes they must be 32bit as most of the applications won't work on 64bit machines.
We have 4,000 cds (ISOs that will be stored and accessed by workstations as required, loading them (I expect they will be stored on server or NAS box, into virtual cd drives on workstations and 164 applications to be installed on each workstation (needed to access data from some of the ISOs.
Would like to use WSUS to provide windows updates to network.
Will use an intranet for in-house stuff and general info.
Would like to use one of the NAS boxes for daily backups storage.
Also like to setup VPN for staff to access there specific info from home.
Administration data to be kept separate from workstations application (ISOs).
Backups of all admin data to be placed on NAS Box.
Using AD and Group Policy on Server to manage user/admin logins and locking down workstations from users doing things they should not be doing (e.g. installing software, changing desktop setting, getting to control panel etc etc).
The RAID controller is a PERC 4e/Di (Embedded).
It has a RAID5 array made up of 4 disks. Size is 558GB.
One disk had failed but the disk and data were still accessible.
The OS is installed on a separate RAID1 which is in optimal condition.
I rebooted the server and it had issues during the boot process. Going into the controller config, it seemed it had lost the information on  all the logical drives. It was giving an error saying NVRAM and disks do not match. All disks showed as 'Online' rather than 'Ready'.

I re-created both RAIDs exactly as before (minus the failed disk) and the server was able to boot back up. However, the RAID5 drive does not appear.
In Disk Management, it shows as: 'Dynamic' Invalid. If I try to reactivate:
'Virtual Disk Manager: This operation is not allowed on the invalid disk pack"

Using OMSA, the RAID 5 array status is 'OK' and there is no issue with the 3 remaining drives.

I found this video using a hex editor to bring up an invalid disk but the situation is different :

Is this a viable solution to recover this disk or is there a better way?
I had 4 x 2tb drives installed and I purchased 4x4 tb ironwolf drives as these were shown to be compatible.

I removed a drive one by one and used the storage manager to rebuild the volume. That all went as planned it just took a day and a half.

The raid used was raid 10 and all the drives passed the smart and ironwolf tests.

I had expected to have 8tb 2.6 used (the previous drives had that amount used)  but it only shows a total of 4.54tb overall.

is that correct for this type of array and drive size? I used the synology drive calculator and that says different. looking at the picture at 37% that seems right 100% would be about the expected 8
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I have a QNAP NAS with an iSCSI LUN, attached to a Windows Server 2012 R2 box. Raid 5, 10TB, thin provisioned.

Deduplication is enabled on the server and volume.

The volume completely filled up, and the disk took itself offline in Windows disk management.

If I hover over the disk, it says 'the disk is offline because it is out of capacity'. If I try to bring it online, nothing appears to happen. If I open the event viewer, I see these two events appear every time I try to bring it online:
Warning: An error was detected on device \Device\HArddisk2\DR6 during a paging operation
Followed by:
Disk 2 has reached a logical block provisioning permanent resource exhaustion condition.

The only way I can bring it online is to use diskpart, but it only comes online in read only mode, therefore I cannot delete any data from it to free up space.

I did manage to bring it online in write mode by attaching it to a 2008 R2 box, but when I delete data, it doesn't update the free space correctly. I can delete GBs of data, but only a few MB are shown as free when looking at the properties of the disk. I suspect this is a result of the dedupe.

The disk does show as having 1GB free now, even in 2012, but it still only comes online in read only mode.

One final thing I tried was to use diskpart to change the read only attribute to 'No', however when I do this, the disk immediately takes itself offline again.

My final option is to move all the data off on to another …
Hi Experts ,

We are building a raid 5 +1 and a global hotspare SSD ( enterprise HP) to host a dc /wsus/app /vcenter/exchange /file.
Now we do not want the hypervisor on the SD card as it is a stand alone HyperV Vmware build and in another country 12 hours flight from us. We think it will be an one point of failover on one sd card.
The idea is to install the hypervisor and host on the same raid .
What are the thoughts about this setup?
Many thanks.
On my R710 server I have a 4tb RAID set up. However, Windows 2012 will only allow me to use the first 2 GB of that drive, so I am guessing I need to switch from a BIOS boot to UEFI. However, how do I get the H700 controller to communicate with uefi instead of BIOS?
Using intel S1200BTL Server board with 4x3TB SATA HDD's.
Would like to have at least 150GB OS Drive and the rest as DATA drive.
Should I use ESRT2 or RST?
Hello all,

I have a HP server DL 580 G5, running VMware vSphere 6 Essentials HP Custom version.
The hardware has 2 RAID controllers Smart Array P400. See attach.

Vsphere for some reason can only see the Embedded RAID controller and not the Controller in Slot 10.
I've tried to install the drivers manually but it doesn't seem to work.
However, If I install VMware version 5.5 it can see the controller in Slot 10.

Can some one point me or instruct me on how to inject or install the correct driver for RAID Controller in Slot 10?
I've included a few attachments. The one in question is vmhba4

Pls let me know if you need more information.

FernandoRAID ControllersStorage Adaptor Slot 10
i have an intel s1200btl mother board trying to install raid drivers.. no drivers to seem to work even from intel site any suggestions
I've got 2 T430s, with an Intel Xeon E5-2630 v4 2.2GHz (10 core), 64 GB RAM, a mirrored 300 GB SAS drive for os & 6 2TB SATA in a RAID 10.
Looking to set up Exchange 2016, network version of Quickbooks enterprise, Trend Micro worry free business security, a remote access server, file & print server, as well as the MS stuff, DC (or 2?) DNS, DHCP, etc.
In complying with licensing, I gather the only role I can have on the host is Hyper-V, which is on my 300GB, would any other VM 'parts" go here, as well?
When setting up VMs, does one VM encompass the OS & data, which would normally be on 2 different arrays the 'old way'?
The two directories for VMs would both be on my RAID 10, correct?
Any suggestions on the best way to spread all my pieces between 4 VMs?
If I've got too much stuff here & would be better splitting between questions, lemme know.
Hi all,

Really need some help please.  Have a small domain network running on 2012 with less than 10 users set up on it that is running painfully slow for all users.  Even saving a 20K file can take a minute.  600MB folder transfer is reporting as needing about 20 hours.

I have just installed this brand new Dell R430 server, 32GB Ram, Dual Xeon Processors, Perc H710 card with 4 x SAS 10K drives in Raid 5 for the main data partition.  Running Server 2012 R2  as a host server and have created a single VM running 2012 Standard which has been set up as a single domain controller/file share with DHCP and DNS server roles. I made sure I updated all of the Dell drivers on the host before installing the VM and have run all updates on both the host and the VM.  There is a brand new 24 port gigabit unmanaged switch into which the server,  a Watchguard T30W Firewall, a Wireless access point, a Synology NAS device and 4 laptops are all plugged in.

I've checked there are no IP conflicts, get a steady ping to the server at <1ms.  DHCP is working fine and there are no issues accessing websites however everything is so slow.

I've disabled VMQ in the advanced properties of the VM Host NIC and also disabled SMB signing so I know the issue isn't with those.

Would really appreciate any pointers.



Info on server :
DL 385 G8
Server is running VMware ESXi 6.0
Controller card P420i

We rebuilt 2x600GB SAS drives in a raid 1 to 2x1200GB without any issue.
When trying to expand the disk space on the logical volume it prevents us of doing this or there is no option as it complains there is a 600 GB Hot-spare drive configured to the same array (Array A).
I do not have any option in ACU on removing of Hot-Spare drive, i have the option to erase the drive.
Will an erase of the drive tell it that it is no longer a hot spare drive ?

How can i remove the Hot-Spare drive ? I would like to repurpose it to another Array B as a hot-spare.

Update, i tried to do this from ESX console using hpacucli using command ./hpacucli ctrl slot=0 array A remove spares=2I:2:8
but got Assignable spares not available (see attached screenshot).

Show command on Array A

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I have a box that I configured to use MD RAID during the install process for the OS and boot drive. It's this weird /dev/md0p# structure that confuses me.

The installer produced /dev/md0p1 (/boot), /dev/md0p2 (/var/lib/mysql), /dev/md0p3 (/), /dev/md0p4 (extended), /dev/md0p5 (swap). I noticed it did this for all physically installed machines from the CentOS 6 DVD.

How do I increase the size of the /dev/md0p3? I need this root partition to be expanded. I feel like I need to delete the /dev/md0p3, /dev/md0p4, /dev/md0p5 partitions and then create a new one for /dev/md0p3 with the extra space. I don't care for p4 and p5, because they don't contain actual data. I can create them after the fact.

I am confused on the order of deleting partitions and adding the space in respect to /dev/md0. fdisk -l shows the drives /dev/sda, /dev/sdb and then finally /dev/md0 with all of the sub partitions.

I have a PowerEdge 730 with H730 RAID controller. I created a RAID 5 array with 2 x hot spares. The total available disk space is about 4.4TB.

I created a single VD using all the available space.

I installed Windows Hyper-V Server 2016 core. During the install I did not manually create partitions since I intended on having only a single partition of all the available space to allocate to VMs so I just selected the raw disk space, which displayed as 4.4TB. This was the first mistake since now the entire partition is MBR. That being said, it only sees 2TB max.

Now I need to shrink the OS partition to about 500GB so I can create 2nd GPT partition so I can make use of the remaining space.

My second mistake is what complicates the situation a little more. I installed and deployed 3 production VMs assuming I had all the disk space to work with.

I have made a backup of the VMS using Veeam backup and replciation and I moved the production VMs to external storage for the time being so I can adjust the C:\ partition.

Now, my question is... Can I use diskpart to shrink the C:\ partition and then create a second partition with the remaining space on a single VD or do I have to shrink the VD in the RAID utility and create another VD.

Is what I'm trying to accomplish possible without destroying the OS?

I know there is always a risk, which is why I have backups, but I would like to do it with the least amount of down time. I've already had the VMs off…
I’m using integrated to mainboard storage controller in RAID1 mode for my Windows Server 2008R2 system.

So one day I’ve corrupted my system and I’ve restored it from full backup, including MBR.

But I’ve got a message that "BOOTMGR is missing" and first thing I’ve decided to do is to load MS DaRT to repair my boot issue and at first boot MS DaRT found some bootable problems and asked me If I want to fix them. I’ve pressed OK : )

After this regular steps the magic had arisen: PC came to reboot and after reboot the problem still here - "BOOTMGR is missing". So, I thought OK, let’s check the MS DaRT again, and while I press to load USB with MS DaRT my system begins to boot.

What the heck?

Now I’m not able to run my system without MS DaRT and also I even can’t run MS DaRT?
Is it a black magic? Please help me!
We have two servers: power edge r610 and  power edge t610.  Both of these servers are displaying in the front panel error;
    w12228 raid controller battery capacity.

Do we have to replace the batteries or can this be fixed by rebooting the server.

How can I get the batteries part # or model for these servers, so that we can order these two batteries.
I am attempting to configure a RAID 0+1 configuration on a Dell Precision T3600.  The drives were previously in service and want to wipe them clean and start from fresh.  My objective is to destroy all current partitions and create a new RAID configuration.  How can I accomplish this within the BIOS Setup Configuration?  I thought CTRL I would allow me to accomplish my objective, but I am not getting an option for CTRL I during the boot cycle.

I was playing around with software mirroring on a Windows 10 box with two SSD drives. There was no increase in throughput between a single drive and RAID 1. I was under the impression RAID 1 should have increased the throughput because there were two drives filling the pipe as opposed to just one but it didn't change much. Why wasn't RAID 1 better?


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.