Questions tagged [software-raid]

RAID solution handled by the operating system.

Software RAID is implemented in the OS. It uses CPU to handle the RAID setup. It is cheaper than hardware raid. It often doesn't support features which you can find with hardware raid like:

  • hot spare
  • fast rebuilding of an array
  • hot swapping
  • high write throughput

Another problem is that it uses the CPU and memory of the computer to perform all the tasks (hardware raidcards have a special cpu and memory for this task). Therefor generating more load on your system.

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Raid 1/10: Kernel panic- not syncing: attempted to kill init

I have setup Raid 1 & Raid 10 in Virtual Box for learning purpose. The following Partitions for 4 Hard Drives: I make a 100mb partition (/boot) on four drives and make that a raid 1 partition. Then with the remaining space on each drive, I've setup…
I'll-Be-Back
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Can I throttle tar without ionice?

My tar command tar --remove-files -cvif 2011-08-02_14-05-09.tar 2011-08-02_14-05-09 Writes 80MB/s. That's beyond the capacity we can spare because MySQL starts queuing up writes and eventually we get monitoring alerts cause systems won't wait…
kvz
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Where is the best place for LUKS to sit in a RAID/LVM/LUKS stack?

I am implementing a server storage setup making use of software RAID, LVM and LUKS. I can think of three combinations this configuration could take: RAID, LVM, LUKS RAID, LUKS, LVM LUKS, RAID, LVM In which order would these best be configured in,…
etheros
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How do I replace a disk marked as removed from a linux md raid-5 array?

I had some recent computer issues and somehow one of my disks ended up not being recognized in my array anymore. It identifies fine, and both smart and some other disk checking utils all say its fine, but somehow the UUID is different. as a result,…
semi
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Poor write performance of software RAID10 array of 8 SSD drives

I have server with Supermicro X10DRW-i motherboard and RAID10 array of 8 KINGSTON SKC400S SSDs; OS is CentOS 6 # cat /proc/mdstat Personalities : [raid10] [raid1] md2 : active raid10 sdj3[9](S) sde3[4] sdi3[8] sdd3[3] sdg3[6] sdf3[5] sdh3[7]…
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Disabling ext4 write barriers when using an external journal

I'm currently experimenting with different ways of improving write speeds to a fairly large, rotating disk-based, software-raid (mdadm) array on Debian using fast NVMe devices. I found that using a pair of such devices (raid1, mirrored) to store the…
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If a RAID controller fails, does it disrupt service until it's replaced?

If I have 2 drives in a RAID 1, and the Raid Controller fails, does that mean the websites on the server will have downtime until the controller is replaced? Or does everything still carry on as software raid automatically until the faulty raid card…
Winker
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How is LSI FastPath different from Software RAID?

This question pertains to SSDs on RAID levels without parity (like RAID 0, 1, 10). The recommended settings for FastPath are to set the Write Policy to Write Through, Read Policy to No Read Ahead and IO Policy to Direct. This disables the cache on…
A.Jesin
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mdadm: drive replacement shows up as spare and refuses to sync

Prelude I had the following devices in my /dev/md0 RAID 6: /dev/sd[abcdef] The following drives were also present, unrelated to the RAID: /dev/sd[gh] The following drives were part of a card reader that was connected, again, unrelated:…
Milos Ivanovic
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Setting up a bootable multi-device (RAID 1) using Linux Software RAID

I'm trying to setup a bootable software RAID that will contain the root filesystem and boot up Linux Mint Qiana. It will be used to run a few graphical monitoring applications in a small datacenter, as well as a simple terminal to access other LAN…
Siler
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Sizing of journal disks with Microsoft Storage Spaces parity volume

I'm currently speccing out a new backup server. It's going to be running Windows Server 2012 R2 with Direct Attached Storage, and I'm considering using Storage Spaces rather than using a RAID card. (As a ZFS fan, I can definitely see the advantages…
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SW SSD Raid 1 over HW RAID 10

A provider(data center) recommended I go with 1TB SSDs in a software RAID 1 over HW RAID 10 with mechanical drives. Their quote: Typically SSDs are most reliable than RAID cards and since you have less parts, there are less points of failure.…
Jason
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Linux software raid fails to include one device for one RAID1 array

One of my four Linux software raid arrays drops one of its two devices when I reboot my system. The other three arrays work fine. I am running RAID1 on kernel version 2.6.32-5-amd64. Every time I reboot, /dev/md2 comes up with only one device. I can…
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How to get notified of mdadm RAID problems?

I am running Ubuntu 12.04 LTS. Yesterday I found a message in my mailbox saying that my server was shut down. I proceeded to reboot the system, but it didn't come up after many minutes, and I didn't have a hardware KVM system to see what the kernel…
Hongli Lai
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mdadm - raid device name changed on reboot

I'm not sure why, but after I restarted my ec2 instance, /dev/md0 didn't start as it normally would. after I saw what's available in /dev/md*, instead of seeing /dev/md0, there is a device there named /dev/md127. I updated fstab to reflect the new…
imaginative
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