Questions tagged [raid6]

RAID6 is a method of configuring fault-tolerant hard drive storage. It is similar to RAID5, but differs in that it writes two sets of parity information, thus can survive the simultaneous failure of two hard drives.

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What's the difference between a "degraded" RAID 6 array and a "clean" RAID 5 array?

Suppose you have two RAID arrays, one with N disks and one with N+1 disks. The array with N disks was formatted as a RAID 5 and left alone, while the other array was formatted as a RAID 6 before one ...
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Re-add physically removed hdd in mdraid having lvm

I have 4 raid6 devices on my server /dev/md0, /dev/md1,/dev/md2 and /dev/md3 each having 9 hdd. I accidently removed /dev/sda1 without removing it from raid md1. When I re-inserted it, raid md1 is not ...
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is the PERC controller limited to 1M of stripe size?

I have a dell powerdge linux (CentosOS8) server with a perc h740p controller and I am testing different strip/chunk sizes for a 10+2 RAID6 array of disks. For what I understood after spending days ...
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2 votes
3 answers
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Need to recover RAID 6 array

By definition RAID 6 is an array of independent hard drives equipped with two independent and distributed checksum schemes Does that mean I can recover each of the hard drives one by one using ...
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I accidently deleted the partition tables of my RAID6 drives

I accidentally deleted the partition table of 2 drives in my 4 drive RAID6 by reversing the order of sudo sgdisk -R=/dev/sdb /dev/sdz parted /dev/sdb print currently reports: Model: ATA ST2000DM008-...
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How do I expand my VD on LSI 9361-16i?

I've got a 9361-16I installed in a supermicro sc847. I have the 2 expanders running in a cascaded configuration with both of them chaining off port 0-4 of the card. They are being exposed as enclosure ...
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Need confirmation on how iSCSI RAID storage works

I have a Dell PowerEdge server with Windows Server 2019 that has an iSCSI target set up with 30 iSCSI LUNs. The HDDs are set up in a RAID-6. I have some IP cameras that have the ability to record ...
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16 drive RAID recommendation on H730P

I have a machine with 16 x 12 TB drives on an H730P controller. What would be the recommended RAID-6 configuration? The drives are of the model Toshiba MG07SCA12TEY I am considering 2x 8 drive arrays, ...
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Is RAID 6 a good choice regarding performance on server used for computation?

We are operating a server for doing computations with large data sets (100GB - 5TB) for a small group of researchers (10-20 people). At the moment we are running 4x8TB spinning drives in a RAID 6 ...
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Issue expanding raid6 array using storcli

I've got a RAID 930-16i 4GB RAID card. I started originally with a single vd comprising of 4 x SSDs in RAID6 ------------------------------------------------------------- DG/VD TYPE State Access ...
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Windows Storage Spaces - a useful replacement for RAID6?

// short update at the bottom // another update is near the bottom to reply to a suggested edit So, at first I had this idea: Find a virtual driver to set up and use software raid on windows. Result: ...
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Adding an Uncofigured Good drive to an existing drivegroup/RAID setup

I have a machine with a few drives in it. Running storcli /c0 show produces this relevant info, et.al.: TOPOLOGY : ======== ---------------------------------------------------------------------------- ...
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How is the HPE SSA "remove drives" command supposed to work to shrink an array?

I have an HPE ProLiant DL380 Gen9 Server with 15 internal 8TB SAS LFF drives, in a RAID6 configuration through an HP Smart Array P840ar controller. It contains a single 94.6 TB Logical Drive [Size: ...
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What would you call this "RAID" ? RAID 1+6? [closed]

I have Snapraid running as snapshot RAID6 (2-parity disks) for my 9 disk array which calculates new parity once a day. Then I have Drivepool duplicating certain very important folders on the array to ...
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How to Add Another Physical Drive to Adaptec maxView RAID6 Logical Drive

I have an ASR71605. I've added another drive to the controller which shows up in max view as ready. The logical drive is RAID 6 with 5 drives in it now. I'm adding this additional drive which is ...
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HP Smart Array P812 - Why is my Raid 60 gone?

I've got an HP ProLiant DL380 Gen7 with a Smart Array P812 which is connected to an MSA20 that houses 19 600GB drives. After my VMs didn't boot up, I checked my array config and 2 drives failed: =&...
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RAID-6 write I/O degrades over time

I've setup a Linux system with RAID-6. Sequential write I/O performance is initially around 600 MiB/s after a reboot, but degrades to between 0.5 MiB/s and 2 MiB/s after the system has been used for a ...
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Upgrading RAID6 drives with larger capacity (Best practices)

I have been tasked with upgrading an existing RAID6 array with new disks. Currently we have a 6 disk setup with 1 hot-swap. This is inside a Dell R340 with a PERC H730 Mini controller. I have not been ...
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How can I find a broken disc?

I have a problem. I got 1 broken disc in RAID6. How can I find which one broke down? I've tried # cat /proc/mdstat <--- to check condition of raid. I want to know if this command mdadm –...
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How to recover mdadm raid6 array? mount: can't read superblock. 8/13 drives show all drives present, 5/13 drives show only 5 drives present

I rebooted my server today to find it hanging. I commented out the entry in fstab that loads /dev/md0 and the machine proceeded to boot. The raid was accessible and working prior to the reboot, I only ...
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Ceph - Erasure Coded Pools - Always get inactive pgs

I'm trying to achieve similar thing to raid6 on ceph. But When I'm creating erasure coded pools (k=3 + m=2(or k=4) ) I always get inactive pgs. ceph health details are: HEALTH_WARN Reduced data ...
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Extend root partition for XenServer 7

The situation: We have a 6 disk RAID6 array in our server. We forgot to keep a bigger space for the root partition and used up all remaining space. Now, if we extent the array with +1 disk and ...
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Expanding Perc 6/E Raid 6 while in use - Can this cause data loss?

There seems to be a lot of information on the 6/i controller but not 6/E. The Dell manual has bit of information on converting from one raid level to another but it does not specifically answer my ...
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(Why) Does lvmraid6 need 5 drives?

I'm investigating using LVMRAID instead of MD+LVM. In my case, I'm looking at a RAID6. As expected, the docs say you need N+1 devices for RAID5, and a minimum of 3 drives. The docs say for RAID 6 ...
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Windows Server 2012/2016 simulated RAID6 in software with 4 disks

Does anyone know how to emulate RAID6 in software on Windows server using 4 disks? The solution must provide for the failure of any two disks (like RAID-6 in Linux). Thank you, Joe
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Can I make an Active Spare disk permanent?

We have a ProLiant ML350P Gen8 server with a P420 controller running ESXi 5.5. It has a RAID 6 array using 7 disks. One of the disks got marked as Predictive Failure, and in response to this we ...
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2 votes
4 answers
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RAID6 failed instantly and switched to RAID0 - any chance to rescue?

I´m running a server ob Ubuntu 16.04. Data storage on this system uses a lvm on top of a software raid 6 whereas the os is installed on a separate raid 1 with lvm. The raid 6 is built up of 7 ...
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4 votes
1 answer
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XFS very slow on LVMed Raid 6

i have a new storage server with 6 x 8TB WD Red HDDs. They build a RAID 6 with mdadm and a chunk size of 256k. On top of that mdraid i have LVM which then holds the different filesystems. Initially i ...
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QNap Nas-Finding drive order for Raid 6

I have a Qnap 10 bay Nas that had two separate raid setups in it. I know that the Raid6 ran from left to right 1~5 slots, and then the Raid5 ran from slots 6~8. They both had hot spare drives in slot ...
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8 votes
4 answers
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Optimal RAID 6+0 Setup for 40+ 4TB Disks

I am setting up a JBOD containing 44 4TB 7200 RPM SAS HDs. I chose RAID 60 as I prefer drive failure protection over the performance improvements offered by RAID 10. My issue is how to choose the ...
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3 votes
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What could go wrong with ext4 on LVM on a hardware RAID6?

Intro Recently one of my systems using ext4 on LVM on hardware RAID6 experienced a disastrous failure. To name some of the disasters: several filesystems failed beyond repair, at least one was ...
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6 votes
1 answer
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RAID6 resync with fast writes but slow reads

I'm using Debian Jessie. # uname -a Linux host 4.9.0-0.bpo.3-amd64 #1 SMP Debian 4.9.30-2+deb9u5~bpo8+1 (2017-09-28) x86_64 GNU/Linux And have setup a RAID6. # cat /proc/mdstat Personalities : [...
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RAID 6 array much faster than my RAID 10 array?

How come my RAID-6 outperforms my RAID-10? Docker container on Synology with 8x4TB RAID-10: [root@centos Files]# bonnie++ -d /Files/tmp -r 16G -s 32G -n 1 -f -b -u root Using uid:0, gid:0. Writing ...
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grwoing raid 6 using mdadm failed - how to undo?

so I have a raid 6 array in my server. Until yesterday, it comprised 11 devices each the size of 1TB. These devices have been running in a raid 6 array. Yesterday i tried to extend the array: Added ...
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2 answers
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RAID 6, 2 disk fail, while third was rebuilding

I have Infortrend DS S16E-G2152-6 NAS, 16 4TB drives (WD4000FYYZ) in RAID 6. Last week one drive failed, was replaced and was rebuilding. At around 80% of rebuild, another two drives failed ...
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mdadm reshape raid6 does not start

Trying to make myself familiar with some of the raid management options before using the actual devices. So I am working with a few small partitions on a USB-stick. The goal is to extend an existing ...
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After creating RAID6 unit mkfs.xfs takes forever

We have a computing cluster with a relatively large storage system with RAID-6. The are 22 disks in this unit and each disk is 3TB (almost 20*3=60 TB). Recently many of the drives failed and rebuild ...
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Poweredge R715 with H700 & SATA drives

I am taking a class that is all about configuring and deploying physical & virtual servers. So as to be able to do this more readily I bought a bare-bones Dell Poweredge R715, 2 Opteron 6276s, ...
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Setting up RAID monitoring on Hetzner server

We are using Hetzner server for our application which is build in Elixir Phoenix. when I do lspci | grep RAID then the results are 02:00.0 RAID bus controller: LSI Logic / Symbios Logic MegaRAID ...
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4 votes
2 answers
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Linux mdraid RAID 6, disks drop out randomly every few days

I have some servers that run Debian 8 with 8x800GB SSD configured as RAID6. All disks are connected to a LSI-3008 flashed to IT mode. In each server I also have a 2-disk pair as RAID1 for the OS. ...
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2 votes
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821 views

How to create degraded raid6 array using megacli

There is a server with few disks. And - a new server with PERC controller. I would like to migrate existing data into a new server to raid6 which uses 6 disks(4+2). Unfortunly - i don't have enought ...
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Which raid array will be best practices with seven 1.2 tb hdd system

I have a server which have seven 1.2 tb hard disks. I have to create raid array but i don't decide which raid i use? First of all, first and most important matter is security. At any cost i must not ...
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Does Windows Server Storage Server have problems with RAID6 iSCSI?

I adopted a virtual Windows Server 2012 Storage Server that has 4 QNAPs attached via iSCSI. The storage environment is connected via iSCSI through a Cisco SG300 (Gigabit); jumbo frames is not ...
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7 votes
2 answers
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Is it possible to ask ReFS to use hardware RAID6 for parity calculations?

Does ReFS use FPGA-based XOR engines for RAID parity calculations? If not, is it possible to get it to use such tech?
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recover original file system from raid6 iso's

I started with 5 drives. 1 has failed (i.e. fails to communicate anything) and 2 more are returning read errors. My plan is to use ddrescue to store the 4 working drives to iso files. After this I ...
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2 votes
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Recovering an RAID6 using ddrescue. mdadm: failed to add, invalid argument

I had 3 drives fail in a matter of a week on a RAID6. Luckily, one drive seemed to be mostly fine. I was able to run ddrescue and it copied all but one small area (couldn't read 14MB out of 3TB). ...
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1 vote
1 answer
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Advice for creating CentOS mdadm software RAID6

EDIT: Solutions to my issue are below I want to create a well optimized RAID6 array with mdadm with an XFS partition on a CentOS system. It'll involve ten ST3000DM001 Seagate 3TB drives and I'll be ...
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3 votes
1 answer
427 views

recover highly degraded raid array

I have a Linux RAID6 array (mdadm) composed of 8 disks. 2 disks failed. I replaced them, now I have 2 new empty disks. I would like to rebuild the raid but when I start a raid rebuild, the rebuild ...
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1 vote
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Perc H700 disk rebuild keeps going offline

I have a Dell Poweredge R710 with a Perc H700 Raid controller. It's in a RAID 6 configuration currently with 2 failed disks. It does boot to CentOS in it's currently degraded state. I would like to ...
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3ware 9650se raid6 replaced with larger drives

I'have been running a setup with 8 drives, each 2TB by now (raid6). I started to build up the setup with 1.5TB drives back few years ago and slowly added and replaced all drives to 2 TB. Now the last ...
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