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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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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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I am running several VMware 5.5 hosts on OEM servers, with each using a MegaRAID LSI 9260-4i SATA RAID controller card with accompanying battery backup unit.   Hosts are managed by a VCenter 5.5  virtual server.  Drive configurations on each host are SATA drives paired in RAID-1 configurations.  I recently got an alarm sounding on one of the servers that 1 of the SATA drives had failed.  I installed the Avago StorCLI utility, and using a  SHOW HEALTH command saw that the state of the virtual drive was degraded, and that the failed drive was on the LSI controller's connector P1.  I shut the system down, pulled out the failed SATA drive, and replaced it with a same-size SATA drive.  On startup the controller card began to beep again, as it was still detecting the degraded virtual drive.  I hit CTRL-H to enter the LSI controller's WEB BIOS and went to add the replacement drive to the degraded virtual drive.  Unfortunately, I could not remove the failed drive from the original RAID-1 Drive Group 0, as it still showed the failed drive in the original mirror setup, as a MISSING PD.  As such I could not add the replacement drive into the original Drive Group 0.  When I tried to add the replacement drive into the Logical Drive setups, the interface created a new Drive Group 1 and wanted to add the new drive to that.  Ultimately I had to declare the new drive as a Global Hot Spare, and I then saw the system start  to rebuild the Drive Group 0 using the new hot spare …
Dell Server Administrator Icon on DesktopDELL OMSMError in opening OMSMI have been runing DELL Server Administrator program to check on DELL T320 RAID Controller/hard drives for a few years without a problem.
All of a sudden, this morning, it would not let me log in after I provide IP address of VMWare Host, root and its password. Basically authentication failed for no good reason.
So I downloaded a new version and installed it. (BTW I did not remove the old version)
Now when I run "Server Administrator", it does not give me the logon screen. It even fails to load the Logon screen.
I tried Https://VSphere:1311 in Internet Explorer and Firefox, but to no avail. (Default browser is Chrome).
VSphere is the name of the Win10 PC that I use to connect to ESXi Host using vSphere Client which still runs fine.

Can you help?
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
I have a Perc 6/i integrated raid controller. Its a raid 5 with about 2tb of storage. There are 4 disk and I replaced each drive one at a time with 4tb drives. I thought the volume was supposed to expand, but im obviously wrong. Am I going to have to copy all the data to a separate drive and reconfigure this thing?

I see in Open Manage there is a reconfigure option for that Virtual Disk.

Here is the physical disk information.
Physical Disks
ID      0:0:2
Status      OK
Name      Physical Disk 0:0:2
State      Online
Bus Protocol      SATA
Media      HDD
Revision      00.0NS05
T10 PI Capable      No
Capacity      2,047.38GB
Used RAID Disk Space      931.00GB
Available RAID Disk Space      1,116.38GB
Hot Spare      No
Vendor ID      
Product ID      WDC WD4000FYYZ-05UL1B0
Serial No.      WD-WMC130E7MAVD
Sector Size      512B
SAS Address      1221000002000000
Non-RAID HDD Disk Cache Policy      Not Applicable
Hello I have a Dell Poweredge T320 and I want to upgrade my 300gb 3.5 15k SAS drives.  I want to upgrade them and am considering SSDs.  Can anyone recommend SAS SSD with storage size around 600gb or higher.   Currently I have a RAID 10 and the T320 has a PERC H310.
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
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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
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?
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 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.)
    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?

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
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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??
Have a pc running with one hard disk. What is the good solution to prevent data loss? NAS / additional hard disk to running raid? any other good solution?
Hi there,
I have a big problem with a server of a client. After the holidays, the server was down. On starting up it complains about a disk error. It is a Proliant ML110 G6 and it has 4 drives configure3d in raid 10. It complaints about 2 bad disks which have been found again.. I replaced one with a new disk, but it says it needs 2 new disks to start rebuilding. So I also replaced the other one (Disk 2 and 4 were bad). The raid controller is a B110 btw. Now it says it is recovering, but on startup it says " A disk error occurred, Press ctrl-alt-del to restart". If I go into the raid bios, it still says "recovering". However I can't see anything and can't hear the drives either. How do I know if it really is recovering, how far it is and what it is recovering?

Hi again guys thanks for all your input previously.  I'll start again.  Starting with 3 sata I found Sata drive 00 was beyond repair, so I had no OS, raid 5. Repostioning the two remaining satas drives to 00 and 01 i installed esxi 5.5 which is stable, raid 0. Reclaiming 3 other sata drives (now a total o 5 drives) i'd now like to use all drives in a new esxi setup (probably losing the first esxi install), can you advise how to bring the extra 3 drives Online?
i'd like to use raid 5 so if a drive collapses again i don't lose all data in my new esxi build, the drives are all various sizes, 00-150Gb 01-150Gb 03-250Gb 04-80Gb 05-1Tb is this a viable setup?
thanks again all. steve.


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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