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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Hi Experts,

I'm trying to build a raid 5 array for our file server using the following:
1.  Dell Poweredege R530 - server
2.  Windows Server 2016 - OS
3.  3x 4TB SAS - Hard Drives
4.  PERC H330 mini - embedded raid controller of dell server

But in my inquiries from diff. forums, I get these ideas:
1.  There's a risk in Raid 5 using large disk, like rebuilding array takes times and probability of failing another disk during the rebuild is more likely to happen.
2.  And raid controller without cache is not wise to use in a parity raid.

Since the PERC H330 is an entry-level raid card which does not have the cache. Is it more wise to use software raid in this situation or stick to using the built in raid controller?
Should I go building the Raid 5 array with 4TB disk?
What's should be the best option for this?


Diagram of the Setup
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User has two locations where they work on their photo library using Adobe LightRoom on Mac.  They are 8 months at first location, then 4 months at the second for the summer.

Can I have a Synology NAS at each location to synchronize their work?

Internet connection in NYC is FIOS, which currently is 600+ mbps using Speedtest both Download and Upload
Internet connection in MA (Massachusetts) is Xfinity which measures 30 Download and 6 Upload

They have about 5 TB of photos on a RAID directly attached to their computer.
I can use software to sync the RAID files to and from the Synology

I will do the initial synchronization of  the Synology units in NYC, and have them bring one to MA

Once in MA
User adds 1 to 2 GB of photos every few days, which will be synchronized to the NAS

At the end of the 4 months, when the user returns to NYC, I would like their photo library and LightRoom catalogs to be a mirror of what they were working on in MA, and ready to use.

Is this a good method?
Any steps missing?

Hard drives keep falling out of RAID 5. I have a custom storage array with a LSI 9260 4I and a HP Array 3GB SAS card.. Every once in a while after patching the server a drive is failed from the array. Check the physical cable and drive and it is still running. I have this mirrored with a synology disk array which works flawlessly. How and what is the best way to confirm if its the LSI Raid card or the HP Array that's causing the drives to fall out. By the way these are 3tb SATA hard drives enterprise level 128mb cache
I'm having an issue with a Thecus n12000pro and would like to get an advice on the way to solve it.

My issue is that after some time the 10 HDD 10K raid 5 stop responding till I restarted the NAS.
I believe the error message appearing on the screen was that the nas failed to mount the volume which is strange because it was mounted and working just before ?
The issue has appeared when I configured the the storage to be used for replication and for active internal storage for a Server hosting VMs

The VMWare 6.5 Internal storage is done in ISCSI through a 10GB link on interface connected directly to the server on a 10GB card
The management of the NAS is done on a third interface through a 1GB link on interface

I tried to add 1TB of SSD cache in writeback mode but it didn't help. I thought that it was a IOPS issue but it doesn't seem the case.
The management is still available on the management interface and we can see that when the issue occur the network is unused on the 10GB interface even if it doesn't answer and the server is freezed due to that situation.
The firmware version is I could try to upgrade the firmware to but I'm not sure it would solve the issue.
Should I backup everything elsewhere and rebuild the whole configuration ? Should I buy another NAS ? Is this a simple configuration issue ?
As you see I need advice :-)

Any help or advice on how to solve this is welcome.

Thanks for …

I've a strange problem with our new Dell Poweredge T640 Server. The Server was originally equipped by Dell with two SSD Drives and a Perc 730P RAID Controller. Everything was fine until we decided to add two more NLSAS HDDs from Dell (2 x 4 TB 7,2K 1/min NLSAS 12Gbit/s 512n, 3,5" Hot-Plug). The server fans jumped to 50% and are very nosiy (constantly even while the CPU is idle). We have 8 slots for HDDs. The first two (0 & 1) are used by the SSDs while the next are occupied by the new NLSAS (slot 2 & 3). We also tried to move the new HDDs to slot 4 & 5 or 6 & 7, but this doesn't help.

We made a update of the firmware, everything is up to date and iDRAC doesn't report any problems. The only thing we observe is that the hypervisor ESXi 6.7 U1 (Dell Customized Image) ist giving us a warning in the hardware logs (attached). Could this be an issue, affecting the fan speed? If yes, how can we fix that? Is there a way to update the drivers ESXi is using or how can I get more information about this reported problem?
We have a Supermicro SMC2208RAid

    Basics :
    Controller = 0
    Model = Supermicro SMC2208
    Serial Number = FW-ACC***********
    Current Controller Date/Time = 02/19/2019, 16:36:25
    Current System Date/time = 02/19/2019, 16:36:40
    SAS Address = 500304800e9c8500
    PCI Address = 00:82:00:00
    Mfg Date = 00/00/00
    Rework Date = 00/00/00
    Revision No =

The second Operating System drive failed:<br>
- Enclosure ID:252<br>
- Slot:1<br>
- Model: `INTEL SSDSC2CW240A3`

This drive is on its own backplane, and is handled by the RAID controller as a RAID1 (mirror) of only two drives.

    EID:Slt DID State DG Size Intf Med SED PI SeSz Model Sp
    0:0 3 Onln 1 1.817 TB SATA HDD N N 512B Hitachi HUA723020ALA640 U
    252:0 28 Onln 0 222.585 GB SATA SSD N N 512B INTEL SSDSC2CW240A3 U
    252:1 27 UBad - 222.585 GB SATA SSD N N 512B U

Because that Intel model is no longer available, we replaced it with a:
`Intel SSDSC2KB240G801`. It is the same size and form factor, with very similar specs. All the critical specs are - I believe - the same EXCEPT this new drive is AES256 hardware encrypted. The old drive was AES128 encrypted. My understanding is;…
I have a Dell poweredge R900 with a Perc 6/i integrated raid controller. The controller only supports 2tb drives, and I only found this out after buying 4tb replacement drives. The server is a good server and won't to utilize it for storage. I was told I could purchase something like a PERC H200 to upgrade the controller. However, when I opened it up there was no sata ports and no sata power cables.

Everything runs from the front of the server into a board that feeds everything. Most of the connectors look like oversized IDE cables (not sure what they are called). I just want to make this a storage server.
Hi I have a RAID 6 Adaptec 7805 Controller

I have 4 SATA drives in a RAID-6 configuration running on Windows 10 Pro for Workstations - under NTFS.

I realize that if a drive fails then the other one takes over.

So here is a few questions

1. How does the RAID controller will help me protect me? (I am assuming it does).
2. Would a bad sector only be detected when it is accessed?
3. If a bad sector is detected - can I assume it is reconstructed from the other good sectors on the other disks?
4. I was considering moving the file system to ReFS with integrity streams on - would this give me any extra benefit?

So what I am looking for is a more detailed explination on how this works. Plus any other info that would be usefull.



Receiving the caution below on the Array. Is it safe to Hot Swap the drive give the drive has not failed? Thanks,

341 1 TB SATA HDD at Port 1I : Box 1 : Bay 2 is predicted to fail soon.

Background parity initialization is currently queued or in progress on Logical Drive 2. If background parity initialization is queued, it will start when I/O is performed on the drive. When background parity initialization completes, the performance of the logical drive will improve.

Logical Drive 2 is undergoing parity initialization
Hello Experts,

We have a HP ProLiant ML350 Gen9 Server running windows server 2012 standard with a Smart Array P440ar Controller.  When this sever was built only a single 1TB HDD was used.  We would like to add another 1TB HDD in a mirror without a large amount of down time.  Is it possible to add another drive and have it mirror without having to do a full backup and restore? Any suggestions are appreciated.

Thank you,

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We had HP ProLiant DL380G5 and I have removed all the low capacity hard disks and now I have purchased 8 refurbished HP 300GB 6G SAS 2.5 inch Hard disk for this server.

Firstly, Plaese let me know what raid type would be best for this file server.

I want to leave one hard disk as a hot spare. Please can you post me tutorials to achieve this.
Thanks and any help would be great.

Secondly will i be able to install windows 2012 standard?

When I turn the PC off and the back on, it starts to boot, but then I get a black screen with "press ctrl+f to enter raid option rom utility". Pressing ctrl+f does nothing and the computer is stuck in a rebooting loop! Please help!
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
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.
I have an old Dell PE2950 server with Perc 6 hardware raid controller in place. I'm setting it up as a storage for backup location. I would like to install 2012R2 on it and use Storage Space. But my question is, do I need to use or configure hardware RAID if I want to use Storage Space? I understand Storage Space does provide RAID feature already.  Appreciate if you can give me some suggestions. Thanks.
Dell T320 Server.    The dell T320 identifier light is flashing amber.  If I push the button it goes to flashing Blue.

1. I've checked the event logs and there are no errors
2. I checked the software raid and there are no errors. States the array is healthy.
3. Power Supply light is green without issue. Error Leds error leds - rear4. Server is running without issue and has been rebooted numerous times by the client.
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We run VMware 6.0 on a Cisco UCS host. There are  6 X 1.2TB HDD in RAID10 giving 3.4ish TB and we are running low on space on Datastore1.  The LSI RAID controller wont let us add disks to the existing RAID so we've created a new RAID1 with 2 x 1.2TB drives.  

Using VCSA, we have moved 3 of our VMs to Datastore2, freeing up 400GB on Datastore1 and now we are trying to extend the size of the virtual disk of our exchange server by 50GB but we get the error

Insufficient disk space on datastore ''.

When we look at the error stack we see "The disk extend operation failed: msg.disklib.NOSPACE"

We cant understand why we are not allow to increase a vdisk when it is reporting that there is more than enough space free.  Any help much appreciated.
Good evening,

I am trying to build a Fedora server with a Raid 1+0.

The mother board is B450-F
Socket AM4

I was able to get Fedora 24 to somewhat work but I made a newbie mistake on a partition and re- installing the system again.
But here is my main problem:

I  have 4 identical solid state drives and want it to be set-up as Raid 1+0.
The hardware does support it but when I try to install linux after the raid has been set-up.  The linux install does not recognize the raided drives.
If I have to deal with CentOS 7 that would be fine.  I just need a system that handle Motif programming, and Fedora and CentOS still support this.

In help would be great
It appears there are some chkdsk errors... this is an old SBS 2008 server... already EOL, we are planning to replace first thing 2019.  

This server has some critical files on it (Accounting, HR, etc)

I am a bit nervous to run the chkdsk /f due to risk of data loss/problems/it running for days... etc... but of course I realize there must be risk running with these errors.

Curious if anyone has any input on how bad these errors might be (given that it does atleast say 0 bad sectors)

See screenshots for details

DELL T30 with SATA disk encouter disk performance issue.
3 x SATA 1 TB HDDs (Software RAID 5)
* does not support hardware controller
* Windows Server 2012R2 Std

After do some checking, notice the disk encounter very high latency on read /write the files.

- System will hang if having a read and write activity.
- Encounter very slow responding when there is some disk running (e.g. copy past document)
- Do a check, CPU and Memory usage is low, only the disk having high activity.

Any idea how can i overcome this issue? without buying a new hardware to replace this.

I'm thinking adding a Synology NAS Storage and attach as iSCSI volume and store all the data.

What do you think?
I have rebuilt a bad Raid array back to healthy. Now when I boot it goes to preparing automatic repair. Any ideas on why it is not booting? I have ran diskpart and the system reserved vol, OS vol, and data vol are all there and showing NTFS Healthy
Dears all,

 I have replaced  two Disks of SAN Storage HP P2000 because they are failed.
 I have Assigned one of them as global SP and the second I have tried to set it as Vdisk by managing dedicated spares but it shows Vdisksp.  
 Please refer to the attachment to view the issue.
1- Can I set all of them as Vdisk( No need for global Sp)?
2-Degraded error show in disk 12  which is Vdisksp (New HDD).
3- San already has DB and supplications installed inside it.
4-We are using RAID 10


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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