RAID, an acronym originally for Redundant Array of Inexpensive Disks (today usually interpreted as referred to as Redundant Array of Independent Disks), is a technology that provides increased storage performance and reliability through redundancy by spreading data across multiple disks using various algorithms (RAID-levels). RAID can be implemented in hardware storage controllers, or in software, usually as operating system/kernel features.
Questions tagged [raid]
3655 questions
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How to resize RAID1 array with mdadm?
I've running Ubuntu 11.04 (kernel 2.6.38-11). I replaced 2x160GB with 2x500GB drives. They are configured as RAID1.
The partition tables show the right sizes. Here's sfdisk:
# sfdisk -d /dev/sdb
# partition table of /dev/sdb
unit: sectors
/dev/sdb1…
Paul Schreiber
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Optimal UNIX File System Partition + Setup Strategy
When partitioning a new system disk(s) for UNIX, what is your prefered strategy for both desktop and/or servers?
Please include disk partition layout, file system format(s) and options, mount points, RAID level(s), LVM groups and volumes,…
cmcginty
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Verify A Partition is Aligned in Linux With RAID and LVM
Does anyone know the steps to verify that a XFS filesystem on top of LVM and md RAID is properly aligned on an array of 4096 Byte aka "Advanced Format" sectored disks?
Some references…
Kyle Brandt
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How do you monitor the health of a mirrored disk in Windows?
I have a Mirrored Dynamic disk on my Windows 2003 Server. How do you monitor the health of the volume?
Is there a way to have the server send an email when there is an issue with the volume?
Is there a way to have the server run S.M.A.R.T.…
NitroxDM
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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 of its disks was removed. Now both arrays have N…
ATLief
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Should I avoid putting two SSDs in a RAID1 configuration due to performance degradation?
I have a workstation system that will have two 64GB industrial SSDs, and the plan is to have both disks in a RAID1 configuration for redundancy which is set up in the kickstart. The system will be running CentOS 7. In looking into this, I…
mochatiger
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How often should I scrub my RAID?
In general I would like to know how often a RAID array needs to be scrubbed. What contributes to the need to scrub more often (reading data?, writing data?, unexpected shutdowns?, drive age?, drive size?, number of users?, etc.)?
I've been reading…
mrfred
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FREENAS: Why isn't mv command instant within a RAIDZ1 volume?
I'm currently 'reorganizing' file structure within a RAIDZ1 volume. Moving directories from one dataset to another, which are both contained on the same volume.
SSH'ed into the machine and did a good old fashioned:
mv * destination
Shouldn't this…
Ryan
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How to upgrade a ZFS RAID-Z array to larger disks on OpenSolaris?
I'm planning on installing OpenSolaris on my home server (right now it has Linux) and I would like to know how to prepare for upgrading the server to have larger hard drives in the future. Now the server has 4x 400GB SATA drives and I would install…
Esko Luontola
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How many disks is too many in this RAID 5 configuration?
HP 2012i SAN,
7 disks in RAID 5 with 1 hot spare,
took several days to expand the volume from 5 to 7 300GB SAS drives.
Looking for suggestions about when and how I would determine that having 2 volumes in the SAN, each one with RAID 5, would be…
Tom
15
votes
2 answers
Unable to mount an XFS filesystem from Linux RAID6 array ("Log inconsistent")
First time poster - my apologies if I don't get the etiquette correct.
I have a ~200TB RAID6 array with 30 disks and I'm unable to mount it - I just get the message:
mount /dev/md125 /export/models
mount:/dev/md125: can't read superblock
If I run…
Bob
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Impact of RAID levels on IOPS
With regard to IOPS, I have seen several sources on the web that suggest the IOPS of a given number of disks is simply the IOPS of a single disk multiplied by the number of disks.
If my understanding of IOPS is correct (and I'm not at all sure it…
dbr
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How to recover an mdadm array on Synology NAS with drive in "E" state?
Synology has a customized version the md driver and mdadm toolsets that adds a 'DriveError' flag to the rdev->flags structure in the kernel.
Net effect - if you are unfortunate enough to get a array failure (first drive), combined with an error on a…
Nathan Neulinger
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Is a large RAID-Z array just as bad as a large RAID-5 array?
For a long time I've heard about how bad an idea a large (>5TB?) RAID-5 array is simply because there's a high risk for another drive to fail.
Has RAID-Z1 managed to remedy this for an array of any size (if you absolutely need a number consider…
TheLQ
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How to remember RAID levels?
How do you remember(if you really do :-)) all the different levels and what each level does? Can anyone suggest an easy way to remember?
BlueGene
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