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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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Any disadvantages of using built-in software-RAID-1 on a Windows Server?

I have had some problems using hardware-RAID on a server. Now I'm planning to use the Windows Server built-in software-RAID-1 instead. The server will only be used for Business Administrations, so I don't need high performance. The operating system…
Jonas
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If two members of a RAID 1 volume have inconsistent bits, how do most RAID controller handle this?

I am using VROC for CPU RAID with some NVMe drives. I have a RAID 1 array that seems to be having problems. Instead of boring you with the details, I have a more general question. How does VROC (or RAID 1 controller in general) handle a situation in…
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TRIM issues with software RAID1 (mdadm) on two different SSDs (size and manufacturer)

I plan to do a server with 2 SSDs in RAID1 (for OS and boot) and 3 HDDs in RAID5 (for data). All Linux (CentOS7) with mdadm. We have in the office 2 leftover SSDs, but they are from different manufacturers and with different capacities (120G and…
Pavel Tankov
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2 x RAID1 vs. RAID10 with four disks

I have a QNAP TS-412 NAS and used two disks so far. I decided to upgrade to four disks and now have options with respect to RAID. I am looking for maximum security against failure of disks (preferably the system should still survive with two disk…
RalfB
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How to Resize RAID partitions on Ubuntu Server 16.04

Recently we configured an Ubuntu 16.04 on Server. We have two 256 GBs SSDs. After a while we recognised that our main RAID partition has only 20GBs while other partition has more than 200GBs. Here's what fdisk -l prints out: Disk /dev/sda: 238.5…
mamsoudi
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Should "System" chunks be included in a btrfs RAID1 balance?

The btrfs wiki RAID1 conversion example gives the following command: btrfs balance start -dconvert=raid1 -mconvert=raid1 /mnt There is also the option -s which `man btrfs-balance page defines as: act on system chunks (requires -f) So, why not…
Tom Hale
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3-way RAID 1 vs. 2-way RAID 1 + hot spare

Assuming the following parameters for a new server storage configuration: All drives are SSD Few large drives are preferred over many small drives RAID 1/mirroring is preferred over RAID 5/6/parity A dedicated hardware RAID adapter is preferred…
Hannes
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Can't get my RAID array out of degraded mode

I've got a 4-drive RAID 10 array that has just had a drive failure. I ignorantly have never practiced how to recover from a failure (I'm a programmer, just keeping this server as a hobbyist) so I'm having to learn this all the hard way right now. I…
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LVM Raid 1 + SSD Caching

I have three disks: /dev/sda slow hdd /dev/sdb slow hdd /dev/sdc fast ssd /dev/vg0 volume group consisting /dev/sd{a,b,c} Each logical volume (lv) should be raid1 mirrored and ssd cached. With the following command, I can create a mirrored raid1…
user1091344
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Bad sector on disk, part of a LVM over RAID1 array, which files are affected?

My RAID1 array /dev/md1 is rebuilding after one of the disks has been replaced. Problem : the source disk has Unrecoverable Errors, and my only choice if I do not want to lose the whole data set (no backup, no excuse) is to patiently write to the…
Hoggins
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Hardware RAID1 configuration - Possibly failed sectors on one physical disk. Does the OS automatically read from the other disk?

I'm not a professional sysadmin but since I couldn't find answers to my specific case after researching for a while I was hoping I could get some help here. Our server uses P222 - a HP Smart controller array in RAID1 configuration. I believe some…
J Doestev
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mdadm 3-way RAID 1 - good solution for guaranteed 2-drive failure tolerance?

Is a 3-way RAID1 using mdadm a good solution to be able to sustain any two drives failing without the RAID failing? I know this costs extra in the sense of only being able to use 1/3 of the disk space (1 out of the 3 drives), but what about aside…
sa289
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Monitoring HP Smartarray (cciss) with nagios

I'm trying to monitor an HP Smart Array controller using nagios. I have 4 disks on 2 RAID1 arrays, so 2 disks per RAID1. I installed nrpe-server and nrpe-plugins and I'm using the almighty check_raid plugin, but it seems to only be seeing my first…
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Write-read errors, Raid1 recovery?

This might sound stupid, but I'm supposed to ask any question here, as long as it is related. So here. I have RAID 1 on the server that is officially soon to be dead. After a chkdsk, the files are corrupting on a more regular basis, and things are…
Olivier Tremblay
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Linux RAID mdadm: what does 'Events' mean?

When I type mdadm --detail /dev/md0 I get a lots of useful information most of which I understand. However I also get a line that reads: Events : 0.710 Where the number varies. Naively, I thought an event either happened or it didn't. How can I…
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