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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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How is the parity calculation in a RAID 6?

In a RAID5, the parity block is a XOR calculation of the rest of blocks but, in a RAID6, the second block parity is the XOR calculation of what blocks? http://upload.wikimedia.org/wikipedia/commons/7/70/RAID_6.svg Thanks
user191550
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Concerns of simultaneous failure of SSD Raid1

Since SSD's have a write limit requiring wear leveling one would assume that all things being equal 2 identical SSD drives would wear nearly identically if they mirror data writes. When one drive fails you can assume the other one is holding on by…
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Progressive upgrade of a RAID array

I have a 16 disk backup RAID6 array. Currently, those 16 disks have the following specs; 500 GB 16 and 64MB cache 3 Gb/s SATA I would like to begin upgrading these disks if possible, primarily for storage. In a perfect world I would be able to…
Alex
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Which disk is bad in raid6 array

Server: Ubuntu Lucid RAID controller: Adaptec 3805 8 disks in RAID6 on HP Proliant DL180 G5 Hardware My kern.log tells me that I have an error on sdb, as shown below: [2740390.344436] sd 4:0:1:0: [sdb] Result: hostbyte=DID_OK…
sixnumber
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PERC 6i / RAID 6 failures

I've got a new server that I'm trying to install a RAID6 config on with a PERC 6i controller and 6 cabled drives. I installed the card, battery and cabled the drives and all looked fine. I installed VMWare ESXi and everything appeared to be fine…
DKNUCKLES
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Which RAID format is best for data privacy during RMA?

So there are several RAID configurations to chose from, and I was wondering, eventually I expect some 25-45% of my drives may need to get swapped for a warranty repair. I know that there is no hope of privacy for a drive that came from a RAID1…
Robert Rolnik
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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 normal (not RAID) recovery software? If no, is there…
Adil Malik
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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 Consist Cache Cac sCC Size…
user13402801
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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 identical to the other 5. (same brand, same model,…
James Hancock
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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 while. I'm using sysbench to benchmark the I/O…
Robert
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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 –detail /dev/md0 will give me the serial number of the…
kernels
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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 reconfigure the array, we can see that the sda have got…
Bert
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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 you need N+2. However, it then says that the…
tudor -Reinstate Monica-
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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 writing a few terabytes at a time, all in files of…
electron.rotoscope
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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 replace the disks, but whenever I add a new one and…
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