a utility to administrate Linux Software RAID devices

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3
votes
1answer
573 views

Recover mdadm raid5 from disk images

My computer just died (won't turn on) and I had some data saved across 4 raid5 disks configured with mdadm. I don't have another computer with sata controllers and want to try to recover using my ...
1
vote
3answers
4k views

configure mdadm for existing intel rapid storage array

i have a raid 1 configured by intel rapid storage from the bios. with windows i have an application which manage the raid. i read about intel rapid storage for linux and found that the option is to ...
0
votes
1answer
323 views

Need to recover data from RAID5 array with just two out of three working disks

When I go to bring up the array with mdadm, it complains I don't have enough components to start it. This makes sense, since RAID5 normally takes a minimum of three disks.. but I don't want to buy ...
4
votes
3answers
5k views

System won't boot unless I type “exit” at initramfs prompt

I installed MDADM for my RAID, and ever since that when I boot up the system just sits at the purple screen forever. After pulling my hair out for a week, I finally discovered - purely by accident - ...
2
votes
0answers
472 views

Raid won't mount on boot after reinstall [duplicate]

Possible Duplicate: MDADM Superblock Recovery So I was having a lot of trouble with Ubuntu after upgrading to 11.10. I decided to do a clean install, and things seem to be much better. ...
2
votes
3answers
39k views

MDADM Superblock Recovery

After a power cycle I found my RAID 5 Array no longer working. I tried various methods to reassemble the array but nothing has worked so far. I believe I need to recreate the superblocks and UUIDs ...
2
votes
2answers
3k views

Can the EFI system partition be RAIDed?

I'm setting up a HTPC with Ubuntu 64-bit, using UEFI and RAID with GPT disks. Is it possible for the EFI system partition (partition type 0xEF00) to be part of a RAID1 array using mdadm? I'm hoping ...
10
votes
1answer
6k views

How do I repair my software RAID5 disks?

I accidentally unplugged my eSATA cable while rerouting some cables behind my desk and knocked my RAID array offline. I believe the drives are fine, but they show up as state "removed" now, how can ...
7
votes
5answers
24k views

How do I rename an mdadm raid array?

For some reason, when I try to rename an mdadm raid array to a textual name, the change doesn't take. I tried the advice from this serverfault question, but to no avail. ~$ mdadm --version mdadm - ...
6
votes
2answers
8k views

Switching mdadm to an external bitmap

I've just read this in another post about improving RAID5/6 write speeds: After increasing stripe cache & switching to external bitmap, my speeds are 160 Mb/s writes, 260 Mb/s reads. :-D ...
2
votes
2answers
5k views

Delete mdadm array but keep data

I have a two-disk mdadm RAID1 array. One of the disks has died so the array is in a degraded state. It's been like this for a while and while I didn't mind getting the occasional email through, ...
3
votes
1answer
504 views

MDADM Array help

I was running ubuntu 11.04 and my boot drive has become corrupt. This has stopped me from accessing my raid5 array. The array was set up in MDADM and called MD0 i think. Can I install ubuntu 11.04 ...
0
votes
1answer
2k views

Testing my raid array / is my mdadm raid working OK? [duplicate]

Possible Duplicate: MDADM Superblock Recovery This may just be me being very stupid but I don't get it! I am new to mdadm raid configuration and my system configuration is as follows: 1 * ...
1
vote
2answers
224 views

What does “md value mismatch_count” count?

Since upgrading to 11.04 I have been trying to get my 5 disk RAID5 array back online. The array was initially split in two, I tried to use a create command with the assume clean option to get it back ...
3
votes
2answers
678 views

How to migrate installed system to RAID1?

I have home server (Ubuntu Server 10.04) which boots from single 80Gb HDD drive, now I want to make it boot from 2x500Gb RAID-1. I've already successfully created it through MDADM. But how can I move ...
3
votes
2answers
677 views

Did I lose my RAID again?

A little history: 2 years ago I was really excited to find out that mdadm is so powerful that it even can reshape arrays, so you can start with a smaller array and then grow it as you need. I've ...
1
vote
1answer
1k views

Should I disable write cache in an mdadm array?

My gut says disabling write cache on soft RAID5 is the smart move, but I'm not certain. Possible Considerations: The drives a WD20EARS with 64Mb cache. The server hasn't gone down due to a power ...
1
vote
1answer
2k views

MDADM: auto re-add dropped HDD

Sometimes hdd might drop out of my RAID, but after I fix HW problem - I have to manually find out which is device name of dropped HDD and manually re-add it. Is there a way to let mdadm scan all HDDs ...
5
votes
2answers
4k views

mdadm: breaks boot due to “is not ready yet or not present” error

This is so damn frustrating :-| I've spent like 20 hours on this nice error, and seems like dozens of people over Internet too, and no clear solution yet. I have non-system RAID-5 of 5 disks, and ...
10
votes
8answers
6k views

Making stripe_cache_size permanent

I did echo 8192 > /sys/block/md0/md/stripe_cache_size to improve my RAID performance, and it did helped alot. But I still can't figure out how to make it permanent. I was trying to set it in ...
3
votes
2answers
14k views

Improving mdadm RAID-6 write speed

I have a mdadm RAID-6 in my home server of 5x1Tb WD Green HDDs. Read speed is more than enough - 268 Mb/s in dd. But write speed is just 37.1 Mb/s. (Both tested via dd on 48Gb file, RAM size is 1Gb, ...
3
votes
1answer
1k views

How do I unmark a “failed” md device?

In an effort to clean up from a software bug in md, I marked half of a RAID (/dev/sda1 and /dev/sdb1 in RAID1) as faulty using: mdadm /dev/md2 --fail /dev/sdb1 mdadm /dev/md2 --remove /dev/sdb1 But ...
5
votes
1answer
13k views

How to access MD RAID via Live CD?

We are currently trying to run access the data on a server running a HP Ml110 G5 SATA raid controller, using the latest Ubuntu Live CD. We need to delete a few files to let the server boot into ...
5
votes
2answers
5k views

Rebuild mdadm Raid5 after OS hard drive died

I have an ubuntu desktop 10.4 "server" with 5 hardrives. 1 of the hardrives had 3 OS's on it (Windows Vista, Windows XP, and Ubuntu 10.4). I primarily used the ubuntu OS so that I could use mdadm and ...
1
vote
1answer
1k views

Mdadm seems to have completely forgotten about a device and shrunk my array

After a bit of investigating of a problem I've just encountered, it looks like mdadm has completely forgotten about a new device I'd added to an array. I recently added a new device to the array which ...
1
vote
1answer
437 views

Does rebuilding a RAID change data?

I've just restarted my computer which was building up a RAID5 for the first time. This of course meant that my computer had to rebuild the whole thing from ground up. Before I restarted the computer ...
3
votes
1answer
535 views

Is it normal that mdadm has to start from scratch when I restart my computer while it's rebuilding the third disk?

I've installed a RAID5 using mdadm yesterday. Since then it has been rebuilding. I just restarted my computer and it started rebuilding the RAID from scratch. (Had 60% before.) Is this normal or are ...
13
votes
4answers
38k views

How do I align my partition table properly?

I am in the process of building my first RAID5 array. I've used mdadm to create the following set up: root@bondigas:~# mdadm --detail /dev/md1 /dev/md1: Version : 00.90 Creation Time : Wed ...