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Questions tagged [raid-1]

RAID 1 is the official name for mirrored disks or volumes

RAID (Redundant Array of Individual Disks or Redundant Array of Inexpensive Disks) is a standardized system for using 2 or more disks to appear as one volume, working together. In the case of RAID 1, the RAID Controller synchronizes all the read and write operations between 2 disks. You only get use of 1/2 the storage using RAID 1.

Because the writes are all synchronized, RAID 1 is not a disaster recovery method of backup; you should still take proper backups to ensure against data loss. If a disk fails, however, the operating system can still access all the data off the other drive until it fails as well.

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Does RAID1 increase performance with Linux mdadm?

I have a cheap 2-bay NAS with a 2TB HDD. To be robust against disk failure, I'm thinking of buying a second 2TB HDD and putting it in RAID1 with Linux mdadm. The file system is ext4. Will this increase or decrease the performance of the NAS? What…
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Simple mdadm RAID 1 not activating spare

I had created two 2TB HDD partitions (/dev/sdb1 and /dev/sdc1) in a RAID 1 array called /dev/md0 using mdadm on Ubuntu 12.04 LTS Precise Pangolin. The command sudo mdadm --detail /dev/md0 used to indicate both drives as active sync. Then, for…
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combining SSD and hard disk in software RAID1?

Does it make sense to build a Linux software RAID-1 (mirroring) using an SSD and a normal hard disk? I want to combine the advantages of SSD (fast transfer rates, fast access times) with the advantages of hard disks (cheap, different fault model)…
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Can a mirrored (RAID-1) disk be plugged into another system to be read?

If I have disks in a RAID-1 array, can I take one of them out and plug it into a different system to be read? This means, on the target system, treating the disk from the RAID array just like an ordinary disk, regardless of any controller/driver…
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Does software RAID 1 in Windows 7 improve read speeds?

Does software RAID 1 (mirroring) in Windows 7 improve read speeds? I'd like to set up RAID 1 to help protect my important documents (yes, yes, I know it's not a backup), but performance is also important to me. As I understand it, RAID 1 should…
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Upgrading disks in a RAID1 Synology 2-bay drive

I have a Synology 2-bay 211j NAS with 2x1TB HDD installed as single RAID 1 volume. I'm running out of space, so I'd like to upgrade my NAS with 2x3TB HDDs. Is there any easy way to copy all data from the earlier 1TB volume(s) to the new 3TB RAID1…
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Does RAID 1 protect against corruption?

Does Raid 1 protect against data corruption? For example, let's say that I am keeping all of my important files on a NAS that uses 2 disks in a RAID 1. If one hard drive has some kind of internal problem and the data becomes corrupted, does the…
Shaun
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What's the difference between RAID 1 software mirroring and Fake RAID?

I've just ordered two new hard drives for my main desktop and a copy of Windows 7 Professional 64-bit. I'd like to do a clean install of Windows 7 onto the new drives (leaving my old Windows XP Professional boot partition around for a while in case…
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Can RAID 1 have more than two drives?

Recently I had a discussion with a teacher of mine. He was claiming that you could set up RAID 1 with five drives and that the data would be mirrored over all of these drives. I told him a RAID 1 with 5 drives wouldn't work like that. It would be a…
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A ZFS or LVM or MD redundant heterogeneous storage proposal

I have the same problem most people have: how to create a reliable personal storage solution with the fact that: Hard drives fail with alarming regularity. Losing files is unacceptable. I will buy a new HDD from time to time. Inevitably, the best…
Bob McElrath
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How does one enable --write-mostly with Linux RAID?

Unfortunately the mdadm and mdadm.conf man pages are not quite up to par. I would like to enable the --write-mostly flag for my RAID, but neither the man pages nor the internet will tell me how. I am not aware of any place to put default arguments…
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How to convert a software RAID 1 partition to non-RAID partition?

RAID is not a backup, they say, but only now I can see that what I really need is an (external) backup. So, I would like to convert a (software) RAID-1 partition to a non-RAID partition (ext4) in my Linux system (Debian 7), but I am clueless how to…
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Btrfs RAID1 SSD + non-SSD

My laptop has two disks, a SSD and a traditional magnetic disk. I plan to make a partition on the mag disk equal in size the SSD and set up BTRFS RAID1. This I know how to do. The only reason I'm doing the RAID1 is for the self-healing. I realize…
Spacedog
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How can I mount a single RAID 1 disk/partition as ext3?

I need to copy data from a single HD, which used to be part of a Linux RAID 1. I've googled around, but can't find any clue how to mount partitions from this single HD. Background: The HD comes from a linux based NAS box Synology DS207+. The NAS…
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How to install RAID drivers on already installed Windows 7?

64-bit Windows 7 Ultimate 6GB RAM Intel i7 920 Intel X25-M SSD 80GB 2,5" Club 3D Radeon HD5750 GA-EX58-UD4P Motherboard I've been running fine with Windows 7 installed on the SSD. I wanted to create an mirrored Raid-1 setup for backups using…
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