RAID (redundant array of independent disks, originally redundant array of inexpensive disks[1][2]) is a storage technology that combines multiple disk drive components into a logical unit. Data is distributed across the drives in one of several ways called "RAID levels", depending on what level of ...

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Grow individual drive size in RAID5 array

My array is built of 3 hard drive of 2TB, I have 2 more free space and I would love to start to grow my array with 4TB hard drives, if I start to put 2 4TB hard drives and eventualy replace the 2TB ...
18
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7answers
12k views

RAID-5: Two disks failed simultaneously?

We have a Dell PowerEdge T410 server running CentOS, with a RAID-5 array containing 5 Seagate Barracuda 3 TB SATA disks. Yesterday the system crashed (I don't know how exactly and I don't have any ...
0
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0answers
17 views

Repairing a RAID5 array [migrated]

For a friend I'm trying to repair a RAID5 array, consisting of 3 2TB disks. After working perfectly for quite some time, the computer (running Debian) suddenly wouldn't boot anymore and got stuck at a ...
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3answers
58 views

How to monitor and rebuild hardware RAID in ESXi?

I'm currently putting together some ideas for a new VMHost using ESXi with RAID 5 to replace 3 aging ESXi hosts that have no RAID. However I can't seem to find any good info explaining how to monitor ...
13
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2answers
3k views

mdadm raid5 recover double disk failure - with a twist (drive order)

Let me acknowledge first off that I have made mistakes, and that I have a backup for most but not all of the data on this RAID. I still have hope of recovering the rest of the data. I don't have the ...
3
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4answers
182 views

Data consistency with RAID 5 and BBWC

I have a few questions about RAID 5, BBWC (Battery Backed Write Cache), filesystem (ext3) and optionally mysql. I have a hypothesis and I ask Server Fault community to validate or not this one: The ...
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0answers
16 views

Partitions not recognized when installing Kubuntu 14.04 over complex RAID setup

I have three identical HDDs. Using a ROM utility, I configured the use of 90% of each of them as a RAID 5 array, and the other 10% as a RAID 0 array. That is, each array uses some area on all three ...
28
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10answers
70k views

Which is better: RAID5 + 1 Hotspare / RAID6? [closed]

Just curious, I have 6 x 1TB 7200RPM Near Line SAS for my new server. I can either configure it as RAID5+1 Hot Spare or RAID6. What should I choose?
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0answers
9 views

raid5 failure on Intel MFSYS25, can't reinstall one server [duplicate]

I'm not a network admin. I am the go between from our contracted IT guy and the bosses because I have I little bit more computer knowledge compared to all other employees. I'll try to be as specific ...
0
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0answers
12 views

Determine RAID 5 config on ubuntu server. Was it hardware or software RAID 5? [migrated]

I am not an experienced Linux or Ubuntu user. I do have many years of software/hardware tech support experience. A customer brought in a DOA Dell Precision 670 Workstation that was set up as a web ...
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0answers
53 views

LVM fault tolerance and recovery over 2 mdraid RAID5 arrays PVs

I have an Ubuntu 14.04 LTS server with an mdraid RAID5 array and LVM on top, meaning one PV and one VG using it. The LVM is configured to allocate all the space to one LV. The LV is formatted with an ...
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7answers
23k views

RAID5 2-disk failure - what steps to take?

I've got a 6-disk RAID5 array on a gentoo server. mdadm is reporting that two of the disks have failed. In the event that the disks are actually gone, I'm prepared to send the drives to professionals ...
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2answers
85 views

PERC H310 Raid 5 - Fault - Turn array into RAID 0

Yesterday one of the three Raid 5 disks I have configured into my DELL Server PERC H310 controller cannot be found anymore. I cannot replace the faulty driver now, so the thing I actually would like ...
7
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2answers
234 views

Windows Server Backup Error - Volumes Larger than 16.7TB cannot be protected?

I'm trying to use Windows Server Backup to backup a RAID array on my new server. But, when I do, I run into this error: The server is running Windows Server 2012 R2 and the array in question is ...
1
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1answer
69 views

RAID-5 how can I guess how many disks was member?

We have a server which we inherited from previous sysadmin. Now the RAID-5 (H/W based on IBM ServeRAID) now unusable, saying not enough disks to operate. On ServeRAID Manager I can see three physical ...
5
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2answers
151 views

How to get Newly Expanded RAID to show correct size in Debian

I recently expanded my RAID 5 Storage Virtual Drive from 6TB to 9TB. The Dell OMSA and the bios for the RAID controller both show I'm at 8382GB. Which is fine. But when get into Debian and poke ...
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1answer
39 views

is it possible to move hard disks in raid 5 to pc without raid controller for accessing the information Temporarily?

I want to rebuild my array (RAID 5) for expansion. In the current configuration, I have 3x320GB hard disks giving me about 600 GB usable. I want to replace these hard disks with 3x1TB hard disks ...
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1answer
22 views

Is it possible to update stripe-width on an existing, and used, ext4 fs?

I have a RAID 5 with 5 3TB drives (8 in few weeks), on a Debian. There is only one ext4 partition on it, using all the space available. Actually, due to origins of the RAID (4 drives), the ext4 fs ...
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1answer
74 views

Raid fault - Dell PowerEdge T11 II

The server is Dell PowerEdge T11 II PERC S100 Virtual Disk Management (Build: 2.0.0-0162) Disk 0 is set too Offline and gives message NOT SELECTABLE: Read error: There is small sound coming ...
2
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2answers
72 views

Missing VirtualDisk on bootup (RAID)

I have a Dell PowerEdge 2950 with DAS storage attached (MD1000) I rebooted the server to apply window updates (win2008), on restart BIOS detected a VirtualDisk was missing and wanted me to continue or ...
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1answer
30 views

Raid-5 Linux Software array, 3 drives “removed”

I have a raid array with several drives marked as removed. I want to add them back in, but am not sure how to do so. [root@tera2 ~]# mdadm --detail /dev/md3 /dev/md3: Version : 1.2 ...
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1answer
203 views

Recovering a RAID5 with 2 disks out of the array

I don't want to approach this in a trial-and-error manner as I know this is the best thing to do if I want to loose my data. I have a server with 4*2TB disks in RAID5 (yes I know it's not wise) on a ...
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1answer
223 views

RAID 5 Data Loss?

Here is what happend. on a ML 350 with a perc 200i controller, raid 5 with 5 disks. 1 Disk got corrupted , and was was on predictive failure flag. On the replacement of the corrupted disk and after ...
0
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1answer
53 views

Would this RAID 5 solution work?

I have a question about RAID 5 rebuilding. Let's assume the following: A RAID 5, 3 disk (5TB each) array (i.e. 10TB useable). If a disk fails, the data remains accessible (e.g. employees could ...
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1answer
131 views

Recovering Linux soft raid 5, disk stays as spare

I got disk failure on my Centos Linux soft raid 5 array (mdadm). I replaced one of the disk and started to rebuild the array. Next time I checked the status, the rebuild was failed. This is the ...
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votes
2answers
190 views

replacing 3 drives out of 8 in a server [closed]

We have a Dell R510 server running SQL 2008 R2 with 8 x 300GB drives running Raid 5. We (just noticed) we had three bad drives with blinking lights so we powered down the server and replaced them ...
3
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2answers
216 views

Software RAID 10 not any faster than s/w RAID 5 on Ubuntu 14.04 box, why?

We are doing some tests on a new database server with 4 x 240 GB SSD disks. From what I have read RAID 10 should be faster than RAID 5 with the same "one-disk loss ok" redundancy. However when ...
0
votes
1answer
89 views

Why is Win Server 2012 slow to read data with RAID 5?

We have new HP 350p server with 4x 900GB 10k SAS disks with RAID 5 (win server 2012). But disks performance to read data is to slow - it's to slow to read big directory structure on disk. Where can be ...
0
votes
1answer
509 views

How to solve performance problems with VMware ESXi 5.5 on old Dell PowerEdge 2900 hardware [closed]

I have a couple of old Dell PowerEdge 2900 servers that have come free and I would like to use them to host a mail server cluster. They are a bit old, but have been running workhorses for a while, ...
0
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0answers
117 views

Sata RAID5 Orphan Drive

so today, one of our hadware RAID5-controllers (Sil3124 (r5), 4x 2TB) went into degraded / legacy mode without any notifications. Additionally, automatically rebuilding the raid-group failed: Event ...
0
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1answer
49 views

Analyze SMART self-test for broken disks [closed]

I recently came home from vacation only to wake up the following morgon with two disks in my RAID5 array marked as faulty. I was able to start the RAID by forcing it to use the faulty disks and run, ...
2
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5answers
11k views

Replacing a dead hard drive in RAID 5 with a different type

One of the drives failed in my server configured with RAID 5, and I can't find a exact replacement. From my understanding, RAID 5 supports drives with different sizes. Is this safe? Any ...
2
votes
1answer
394 views

RAID5 array Ready for Rebuild

I've inherited administration of a server with a RAID 5 array. We have a damaged database on the array that is just over half the allocated size, so makes recovery impossible. I recently changed the ...
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1answer
47 views

Removing HDD from RAID 5 to pull data from

I have a relatively (I think) simple question... I have a file server with RAID 5 that is old and pretty much dead and I need to grab the data from it. I was thinking I could pull one of the HDD's ...
0
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0answers
135 views

Low disk I/O causing high disk busy and CPU wait

I have an Ubuntu 10.04 server on VMware that is experiencing 99% disk busy with only 1 MB of disk I/O according to nmon. 300 KB of disk I/O causes 25% to 30% disk busy. iostat reports the same: ...
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3answers
1k views

Server 2008 RAID 5 Write Speeds

I recently configured a RAID 5 partition in Server 2008 with 4 RAID 5 disks. These disks are connected through a SATA expansion card that uses PCIe. This morning, I checked and they had finally ...
0
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1answer
173 views

Windows 2008 R2 server software RAID-5

After one of the reboots (normal one after windows update) Windows 2008 R2 marks software RAID-5 disks (OS-Based) as "Invalid". RAID structure is intact - I can see it via R-STUDIO. All data are OK ...
10
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2answers
1k views

What counts as a 'large' raid 5 array?

A recent issue with a Buffalo TeraStation NAS here in my office has got me investigating Raid 5. I've found a few different articles talking about the unsuitability of using raid 5 in large arrays, ...
1
vote
2answers
269 views

How can you force linux software raid not to disable a disk for recovery?

I'm trying to recover data from a RAID5 array. 2 of my 4 disks unexpectedly failed at the same time. I am able to start the array by forcing it. mdadm --assemble --scan --force The array starts up ...
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votes
2answers
77 views

Can a RAID5 be corrupted if Drive 0 has been failed and how could this be fixed? [closed]

I have configured RAID5 on an ASUS server and installed VMware ESXi 4.1 on it. The attached photo indicates that Drive 0 resides in a Failed state. All Hard Disk Drives (HDDs) are running Normal. ...
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votes
1answer
59 views

Can I pull raid 5 disk from IBM X365 to put into another X365

I have an IBM X365 that is sitting in a corner. It has the same size drives as the IBM X365 that has a failed drive. Both have Raid 5. Can I pull drive from the one sitting in the corner and ...
2
votes
1answer
62 views

Raid 5 URE rate [duplicate]

I've recently read this post: http://www.standalone-sysadmin.com/blog/2012/08/i-come-not-to-praise-raid-5/ tldr; It basically says that the error rate of a RAID system is tied to the hardware, and ...
1
vote
1answer
47 views

Optimize unused space in RAID5 due to bigger HDD in spare parts change

I have started with 3x250 GB SATA array, but the old HDDs failed one by one and when the spare parts came they where bigger disk inside and I recently ended up with 3 HDDs of 500 GB. I see ...
2
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2answers
222 views

How to identify which hdd to be replaced in RAID

Our RAID5 (using Adaptec 3085) stopped working because one of the hdd is broken. How can I identify which one it is?
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1answer
1k views

Repair HP SmartArray p410i

i have an HP proliant server and in the last 4 years i never had a single problem with it. but yesterday i found out that i cant remotely login to my server so i went over and found that one of three ...
0
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1answer
87 views

When exactly does a RAID5 reconstruction happen?

Let's assume the following scenario: A RAID5 array consisting of 3 disks is happy and running One of the disks crashes We replace the broken disk with a spare one The system is up and running again ...
1
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1answer
2k views

Cannot reactivate RAID-5 volume: The size of the plex member is invalid

We had a 3-drive Windows Server 2008 R2 RAID-5 fail (operating in redundancy mode): WDC 1 TB WDC 1 TB WDC 1 TB We removed the failed hard drive, and put a WDC 1 TB drive (that we had standing by) ...
3
votes
1answer
75 views

Reading /proc/mdstat

I just built my first raid5 yesterday (with 4 hds) and was reading about monitoring with /proc/mdstat. My understanding is an ideal dispaly with 4 drives should be [UUUU] however mine reads [UUU_]. ...
5
votes
4answers
5k views

How do I configure RAID 5, especially stripe size, with 24 x 1.2 TB drives for CentOS 6?

For a Dell R920 with 24 x 1.2TB disks (and 1TB RAM), I'm looking to set up a RAID 5 configuration for fast IO. The server will be used to host KVM VMs that will be reading/writing files of all sizes, ...
0
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2answers
1k views

3Ware 9500s Raid array not visible in Windows 7 x64 disk management - latest firmware and drivers

I bought a used 3Ware 9500s-4LP raid controller from Ebay (the old 3ware 8506-4lp didn't support RAID arrays over 2TB, but it was working), installed it in my server and attached it to the SATA ...