RAID - Redundant Array of Independent Disks. A Storage technology to provide redundancy and performance, to reduce I/O bottlenecks involved in using multiple disks for large storage.
9
votes
2answers
744 views
Choosing filesystem for a 16TB Raid
I'm just putting together a machine with eight 2TB disks.
I will be using Raid 6 (12TB of usable capacity) on top of them, but I'm not sure whether I should make LVM on top of the RAID, or what ...
8
votes
2answers
2k views
Whats the difference between mdadm state “active” and state “clean”
I two different computers with different RAID5 arrays. When I run the command
mdadm --detail /dev/md0
one drive reports "active" while the other reports "clean" for the "state" field. What is ...
6
votes
2answers
1k views
Will the system make sure that mdadm is sync-ed before completing a reboot?
This is a follow up to my crazy mdadm problem. I'm trying to figure out what might have caused sda to get out of sync in the first place. The only thing I can think of is that I had just run a bunch ...
5
votes
5answers
687 views
Consumer Level software RAID5 and LVM
Hi I am going to build a 6 drive consumer level RAID 5 (10TB) with Ubuntu10.10 and using EXT4 as filesystem, and OS on another drive.
Question: Should you use LVM on top of the RAID5 or should just ...
5
votes
3answers
6k views
How to check mdadm raids while running?
I'm starting to get a collection of computers at home and to support them I have my "server" linux box running a raid array.
Its currently mdadm raid1, going to raid5 once I have more drives (and ...
5
votes
1answer
1k views
mdadm Raid5 gives spares missing events
I succesfully builded up a raid5 array on debian testing (Wheezy). As the manpages and further tell, the array would be created as an out of sync array with just a new spare injected to be repaired.
...
5
votes
6answers
2k views
Pros and cons of software Parity-RAID (e.g. RAID5)
I was recently told about some problems concerning Parity-RAIDs without a non-volatile cache. More exspensive HW-controllers do have battery-powered caches to finish write-operations in case of power ...
5
votes
2answers
377 views
In place upgrade of a software raid 5 array
I run a software raid array for my backups, but my data has outgrown capacity.
considering I have a full 2.4TB array with 5*600GB drives and also have 5*2TB drives I would like to swap in.
What ...
4
votes
2answers
116 views
Where did 47gigabytes of space go?
Clean installation od Debian squeeze 6.0.6 x64 on intel atom 230, with 3 HDDs, with 3x500GB.
df -h shows :
datastore size used free % mounted
/dev/md0 917G 909M 870G ...
4
votes
3answers
268 views
What would be a good choice for an elastic file system (for adding storage at a later date)?
I'm currently running a Debian 6.0 server with EXT3, but I'd like to move over to Arch. It's being used as a file server right now with a 1TB drive in it (of which 650GB in it is used). What I'd like ...
4
votes
1answer
104 views
ext4 directory lists as a file
I'm working with a large (8TB) EXT4 filesystem in linux. After a power outage, the filesystem wouldn't mount. fsck is taking weeks to complete, but i ran testdisk and i'm able to see my partition ...
4
votes
1answer
226 views
Alternatives to LVM
I was thinking about alternatives to combine several HDDs together.
The only options I know so far are using LVM and/or RAID.
The thing is, using LVM, I will most probably lose all data, if one ...
4
votes
3answers
964 views
Using mdam --examine to write mdadm.conf
I'm trying to script the RAID setup for a (growing) number of identical servers. The advice I've seen for using mdadm suggests that once the RAID array has been created you can run mdadm --examine ...
4
votes
1answer
705 views
RAID 10 can not be started
I have a RAID 10 array managed with mdadm which has failed . The symptom was that X has crashed and I was unable to logon from the terminal. I have restarted the computer and /dev/md1 did not start.
...
3
votes
3answers
1k views
Mounting multiple devices at a single mount point on Linux
Is there a way to mount multiple hard drives to a single mount point? Let's say I run out of space on /home and decide to add an extra hard drive to the computer. How do I scale the space on a mount ...
3
votes
1answer
264 views
Unable to mount raid on my NAS, trying to rescue the data, how should I proceed?
A short backstory: something happened on my Synology NAS, apparently a buggy mailserver program that came with an update stopped the device from seeing the 2x3TB drives I have. After a lot of ...
3
votes
3answers
428 views
Is creating a sparse image using dd appropriate for backup/restore from a RAID?
I have two non-networked servers, each with 1.2TB of storage in a RAID5 config on an LSI MegaRaid 9240-8i controller. I have been trying without success to get Symantec Ghost to image one machine to ...
3
votes
3answers
654 views
Avoid pause during dm-raid initialization
On my CentOS 5 workstation I get a few seconds wait after dm-raid45 has been loaded ("Initializing Driver" or something like that).
This seems to be part of the initrd. After that the system boots ...
3
votes
2answers
101 views
View Files from mirrored RAID outside the device
The Product I have is a Western Digital My Book
The device has stopped working but there is nothing wrong with either of the two mirrored drives. I would like to take out the two mirrored hard ...
3
votes
1answer
917 views
installing grub 2 on mdadm, which device?
when installing grub(2) to mdadm devices are you supposed to install it to /dev/sdX or /dev/mdX?
3
votes
2answers
87 views
RAID Lag-Behind Burst Write
I would like to setup RAID1 so that a ramdisk in the RAID configuration has occasional synchronisation with a physical disk (that is very battery intensive to run, so I hope to let it spinout).
Is ...
2
votes
2answers
407 views
Very slow SW-RAID 5 in Debian Squeeze
I don't know why, but I have big trouble with speed of my raid.
I have 4x WD RE4 7200RPM 500GB. Size of RAID 5 is 1000GB. 1 of HDDs is Spare.
Problem is here:
Every 1,0s: cat /proc/mdstat ...
2
votes
3answers
150 views
Can I create a software RAID 1 with one device
I have a single disk that I want to create a Mirror of, Lets call this disk sda I have just bought another identicle size disk, which we can call sdb. sda and sdb have one partition called sda1 and ...
2
votes
1answer
801 views
Why does btrfs allow to create a raid1 with mismatched drives?
I'm creating a btrfs using
sudo mkfs.btrfs -m raid1 -d raid1 <small-disk> <large-disk> or
sudo mkfs.btrfs -m raid1 -d raid1 <large-disk> <small-disk>
it creates the fs with ...
2
votes
1answer
692 views
Interpreting tiobench results
I'm running tiobench on my raid1 and it gives me the following results.
Why is there ##### shown instead of throughput?
Why does seq.reading with 8 threads use 2836% CPU?
My results:
$tiobench
No ...
2
votes
1answer
306 views
Drive was unable to assemble into the array
I ran
mdadm -A /dev/md0 /dev/sda1 /dev/sdb1
Only /dev/sdb1 was loaded into the array though. I have a few more arrays on the same two drives too. Each time the partition on sda failed. dmesg told ...
2
votes
1answer
139 views
Ubuntu Software Raid5 - /dev devices changed, will mdadm raid break
I had a major server failure. The OS is fine and back up and running. Before I plug my raid drives back in and try and mount it I need to ask this simple question.
The drives that originally mapped ...
2
votes
1answer
208 views
Migrating from hardware to software RAID
I have an old PCI-X controller running 8 drives in RAID 5. I'd like to dump the controller and go to software RAID under Ubuntu. Is there a way to do this and retain the data from current array?
...
2
votes
1answer
1k views
Linux: LUKS and multiple hard drives
I have a Debian Linux system (amd64) installed on a RAID-1 system encrypted device (LVM on LUKS) and will have a RAID-6 of >=4 disks where I'll put my data (LUKS and maybe LVM).
I think the basic ...
2
votes
1answer
90 views
Rosewill RC-212 and Fedora 15
I recently bought a Rosewill RC-212 and configured it in the BIOS for RAID0. Windows 7 recognizes the array without any extra drivers and installed to it without problems.
I installed Fedora 15 on a ...
2
votes
3answers
665 views
Linux + how to verify mirror configuration on linux red-hat
I have an IBM blade server and we've installed RedHat Linux on the machine.
How can we check if we have both disks running as a mirror, or if everything is only running on a single disk? What ...
2
votes
3answers
143 views
Partitioning EFI machine with two SSD disks in mirror
I have two SSD disks, I want to put them in a software mirror RAID.
But whatever I do the OpenSuSe installation keeps telling me that due to the partitioning scheme he won't be able to install the ...
2
votes
1answer
335 views
curious soft raid 5 setting inconsistency
Lately I bit the bullet and upgrade my OS from Fedora 11 to Fedora 15, and I've been trying very hard to figure out why Fedora 15 can't see the Raid setup that I created in Fedora 11. I think I must ...
2
votes
1answer
42 views
cleaning /dev/md0 filesystem ( raid)
I have a CentOS server using raid.
The /proc/partitions contains:
major minor #blocks name
8 0 976762584 sda
8 1 104391 sda1
8 2 921600855 sda2
8 3 55054755 ...
2
votes
2answers
287 views
Change Partition Table with GParted
I have an Ubuntu 12.04 LTS server that has 6x600GB SAS drives in a RAID 5 configuration (Perc 6/i).
The partition scheme looks like this:
Partition File System Mount Point Size
/dev/sda1 ...
2
votes
0answers
100 views
Disable RAID auto detect at runtime
In Linux, I'm partitioning two disks for RAID1 with fdisk. The first disk partitioning succedes, but the second fail because the raid starts automatically and occupy also the second disk (why? it ...
2
votes
0answers
253 views
Bad superblock after server crash
My server (CentOS 6) crashed, and it now kernel panics on boot. It's currently using a mdadm RAID1 array with two 1TB drives.
vg_server2422-LogVol01 is /
vg_server2422-LogVol00 is Swap
...
2
votes
0answers
240 views
Media server RAID difficulties (on FreeNAS)
Disclaimer: I've never used FreeNAS or any type of RAID before, so this is a first.
I've decided to build a media server in my new apartment. I'm going to be going with a total 10TB of space (6x2TB ...
2
votes
0answers
223 views
Software raid checksumming slow
On my new 24 disk array I get 900 MB/s of raw read or write using dd to all the disks.
When I set the disks up as a 24 disk RAID6 I get 400 MB/s write and 600 MB/s read. It seems to be due to ...
2
votes
0answers
525 views
Linux Mint installer does not see fakeraid drive
I have a computer with a fakeraid 0 array (the computer came with it, and I don't want to remove my other OS to get rid of it), and I am trying to install Linux Mint. When I first boot up from the ...
1
vote
2answers
324 views
Is their a 'friction free' way to convert RAID1 to RAID5?
What's the best way to convert Linux software RAID 1 array to RAID 5? ( I have already bought the 3rd Hard Disc !)
1
vote
2answers
131 views
Move Web Directory to Raid Array
I want to improve the performance of a web application running on Apache, so I created a Raid Array on /dev/md0.
Now I need to figure out how to move the application to the array and make sure that ...
1
vote
1answer
29 views
Can I put 2 disks into a raid-0 array without reformating the FS?
We have an existing /dev/sda disk, we are adding an identical /dev/sdb
I want to place these two disks in a raid-0 array.
Can I do that without reformating /dev/sda?
1
vote
2answers
229 views
Linux software RAID-1 and device name
I want to set up software RAID-1 on my Ubuntu system, and found this example of an /etc/raidtab:
raiddev /dev/md0
raid-level 1
nr-raid-disks 2
nr-spare-disks 0
...
1
vote
1answer
133 views
RAID 1 + 0, Solaris 10
I create the meta devices:
metainit d102 1 1 /dev/dsk/c1t2d0s6
metainit d103 1 1 /dev/dsk/c1t3d0s6
metainit d104 1 1 /dev/dsk/c1t4d0s6
metainit d105 1 1 /dev/dsk/c1t5d0s6
then I make the mirrors ...
1
vote
2answers
183 views
Can't remount local file systems for read-write (RAID1)
I assembled a new machine on Asus P9X79 motherboard, using its RAID controller to create a RAID1 array of two 500Gb drives.
When booting Arch from an external drive I am able to work fine with ...
1
vote
1answer
2k views
Raid 0 Linux Installation fails to install grub
I have a Raid 0 setup (striping) via BIOS not through software raid. When I install linux mint or Ubuntu it fails to install the boot loader or set the boot loader to boot. I get an error stating ...
1
vote
2answers
427 views
Software raid + separate partitions?
I have setup software RAID1-arrays using two 250GB harddrives. There's two arrays - one named md0 in which the system is kept and the other, md1 works as swap:
# cat /proc/mdstat
md0 : active raid1 ...
1
vote
1answer
254 views
Complete install on RAID1 + LVM
When doing a complete install of Linux is it possible to install everything including /boot on 2 software RAID 1s (4 hdds) + LVM?
I haven't been able to figure out whether this is definitely ...
1
vote
1answer
55 views
ServeRAID error in syslog, is it important?
I was checking the logs in server when i came across this message.
Nov 4 12:52:05 SERVERNAME ServeRAID Manager Agent: [338] Periodic scan
found one or more critical logical drives: controller 1. ...
