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Questions tagged [raid1]

RAID 1 or Mirrored RAID uses two or more disks that store the same data.

RAID Level 1 or mirrored RAID uses two or more disks that store the same data. One disk is mirrored to the other. Write speeds are the same as using one disk, and read speeds are twice as much.

RAID 1 is used when reliability needs to be higher than normal.

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mount: unknown filesystem type 'linux_raid_member'

I have Suse Linux 12.1 and i am trying to mount a single RAID 1 disk, to explore the files in it. However when mounting it: # mount /dev/sdc1 /mnt/test mount: unknown filesystem type 'linux_raid_member' I started reading around and many…
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Should I 'run in' one disk of a new RAID 1 pair to decrease the chance of a similar failure time?

I'm setting up a RAID1 array of two new 4TB hard drives. I heard somewhere previously, that making a RAID1 array of new identical hard drives bought at the same time, increased the chance that they would fail at a similar point in time. I am…
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Why is RAID 1+6 not a more common layout?

Why are the nested RAID levels 1+5 or 1+6 almost unheard of? The nested RAID levels Wikipedia article is currently missing their sections. I don't understand why they are not more common than RAID 1+0, especially when compared to RAID 1+0 triple…
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How to re-add a drive when RAID is in degraded mode?

I am running an unmanaged Ubuntu server and due to recent performance issue and sent a request to the provider only to receive the following response: "Dear Client, as requested we have checked your drives. Both drives pass a test without any…
captain lizard
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Low-end hardware RAID vs Software RAID

I want to build a low-end 6TB RAID 1 archive, on an old pc. MB: Intel d2500hn 64bit CPU: Intel Atom D2500 RAM: 4GB DDR3 533 MHz PSU: Chinese 500W NO GPU 1x Ethernet 1Gbps 2x SATA2 ports 1x PCI port 4x USB 2.0 I want to build a RAID1 archive on…
Igor Z.
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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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When adding a new disk to RAID 1, why does it sync unused space?

I recently set up RAID 1 on Linux with mdadm. When adding a new HDD to RAID 1, data started to sync between my drives which is expected. I didn't expect that it started syncing the entire drive, including unused space. The HDDs were 6 TB with only…
idunnololz
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Is RAID5 more robust than RAID1

I am about to replace an old hardware RAID5 array with a Linux software RAID1 array. I was talking to a friend and he claimed that RAID5 was more robust than RAID1. His claim was that with RAID5, on read the parity data was read to make sure that…
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HP Smart Array P410: Convert RAID10 to RAID1 OR remove disks from RAID10

I have a server with two RAID10 arrays of 146GB disks. I'm trying to replace one RAID10 array of 146GB disks with RAID1 of two 2TB disks. Since there are no free ports, I took out two disks from the array which I am going to replace. Now the status…
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Getting files out of XFS with 64kb block size

I've been on a mission to recover files from one of my 2 perfectly working, non-corrupted, non-encrypted NAS drives that used to be in RAID 1. The NAS was Patriot Javelin S4, which (as I found from my research) uses Promise Fasttrack fake raid…
Max Chernyak
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How to obtain read speeds of two disks using mdadm/btrfs raid1 or zfs mirror?

Given that RAID1 writes two copies of the data, my understanding is that reads should be close to twice that of a single disk. I have tested read performance of different technologies (mdadm, zfs, btrfs) with little success. From my…
Greg
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What's the difference between "mirror" and "raid1" in LVM?

On the lvconvert(8) man page it says: --type SegmentType Used to convert a logical volume to another segment type or to explicitly state the desired RAID1 segment type ("mirror" or "raid1") when converting a linear logical…
Julian
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How to make a Linux software RAID1 detect disc corruption?

This is one of the nightmare days: A virtualized server running on a Linux SW-RAID1 runs a VM that exhibits random segfaults in seemingly random codechunks. While debugging I find that a file gives different md5sums on each and every run. Digging…
Paul
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How to attach an existing RAID1 to a fresh Linux system?

I have a RAID1 currently operating on a single hard drive (yes, the mirror is absent). Is it possible to reorganize my system using the following algorithm? I set up another single-disk RAID1 (onto another HDD of the same type), partition it and…
dpq
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mdadm: Which disk is being rebuilt?

I noticed my software RAID1 degraded, and wanted to figure out which of the two disks in the array is being rebuilt/re-synced since they both show as being up. I am hoping someone can shed some light on this, if it's even possible to figure out…
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