LinuxQuestions.org
Visit Jeremy's Blog.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Hardware
User Name
Password
Linux - Hardware This forum is for Hardware issues.
Having trouble installing a piece of hardware? Want to know if that peripheral is compatible with Linux?

Notices

Reply
 
Search this Thread
Old 07-20-2009, 10:43 AM   #1
TexasMike
LQ Newbie
 
Registered: Jun 2006
Posts: 19

Rep: Reputation: 0
Unhappy Assembly problems with Raid 5 Array


Hello all,
My system: Gigabyte MB with Intel Core2 Quad, 6GB RAM, 3 internal SATAII drives, I internal SATA DVD/CD drive R/RW, Symbios SCSI controller and an external SUN D1000 Drive enclosure with 12 36GB SCSI drives in a Raid 5 Array with 10 disks in the Array and 2 spares.

I am having a problem getting my Raid 5 Array to "re-assemble" and mount. This array was working fine, but a power "blink" caused it to power off last Thursday (July 17, '09). When the Array was powered back "On" and the PC re-booted, I noticed the array was not available and tried to get it to mount - array will not mount. I then tried to re-assemble the array manually with the following command and results:

Quote:
sudo mdadm --assemble --verbose /dev/md0 /dev/sdd1 /dev/sde1 /dev/sdf1 /dev/sdg1 /dev/sdh1 /dev/sdi1 /dev/sdj1 /dev/sdk1 /dev/sdl1 /dev/sdm1
mdadm: looking for devices for /dev/md0
mdadm: /dev/sdd1 is identified as a member of /dev/md0, slot 0.
mdadm: /dev/sde1 is identified as a member of /dev/md0, slot 1.
mdadm: /dev/sdf1 is identified as a member of /dev/md0, slot 2.
mdadm: /dev/sdg1 is identified as a member of /dev/md0, slot 3.
mdadm: /dev/sdh1 is identified as a member of /dev/md0, slot 4.
mdadm: /dev/sdi1 is identified as a member of /dev/md0, slot 5.
mdadm: /dev/sdj1 is identified as a member of /dev/md0, slot 6.
mdadm: /dev/sdk1 is identified as a member of /dev/md0, slot 7.
mdadm: /dev/sdl1 is identified as a member of /dev/md0, slot 8.
mdadm: /dev/sdm1 is identified as a member of /dev/md0, slot 9.
mdadm: added /dev/sde1 to /dev/md0 as 1
mdadm: added /dev/sdf1 to /dev/md0 as 2
mdadm: added /dev/sdg1 to /dev/md0 as 3
mdadm: added /dev/sdh1 to /dev/md0 as 4
mdadm: added /dev/sdi1 to /dev/md0 as 5
mdadm: added /dev/sdj1 to /dev/md0 as 6
mdadm: added /dev/sdk1 to /dev/md0 as 7
mdadm: added /dev/sdl1 to /dev/md0 as 8
mdadm: added /dev/sdm1 to /dev/md0 as 9
mdadm: added /dev/sdd1 to /dev/md0 as 0
mdadm: /dev/md0 assembled from 6 drives - not enough to start the array.
and here is the result of cat /proc/mdstat:

Quote:
root@UE-2:/home/mike# cat /proc/mdstat
Personalities :
md0 : inactive sdd1[0](S) sdm1[9](S) sdl1[8](S) sdk1[7](S) sdj1[6](S) sdi1[5](S) sdh1[4](S) sdg1[3](S) sdf1[2](S) sde1[1](S)
355597440 blocks

unused devices: <none>
I do not see the reason the system is only using 6 of the 10 drives. Is there an error log file for mdadm specifically?

Any advice or pointers would be most welcome...

Regards...

TexasMike
 
Old 07-21-2009, 01:12 PM   #2
zeno0771
Member
 
Registered: Jun 2006
Location: Northern IL
Distribution: Arch64
Posts: 106

Rep: Reputation: 19
I mount mine without partition numbers, i.e.,
Code:
sudo mdadm --assemble /dev/md0 /dev/sda /dev/sdb /dev/sdc /dev/sdd /dev/sde /dev/sdf
mdadm gives me a bunch of hell if I try to mount my array with the partition numbers; I have to restart my array so rarely that I forget about that myself half the time.

Restart the box (or stop the existing array and fail/remove the array, whichever is faster) so you have a clean slate. Then assemble without partition numbers. Of course if you have multiple partitions on the drives that won't work but if you're using RAID 5 you probably don't.
 
Old 07-23-2009, 08:30 AM   #3
TexasMike
LQ Newbie
 
Registered: Jun 2006
Posts: 19

Original Poster
Rep: Reputation: 0
zeno771,
Thanks for the reply. I have never used the Assemble command without the partition numbers - didn't even think to try it without the numbers...
Anyway, I rebooted the system and issued the command:
mike@UE-2:~$ sudo mdadm /dev/md0 -S

I then issued the following command:
Quote:
mike@UE-2:~$ sudo mdadm --assemble --verbose /dev/md0 /dev/sdd /dev/sde /dev/sdf /sev/sdg /dev/sdh /dev/sdi /dev/sdj /dev/sdk /dev/sdl /dev/sdm
Here is the response:
Quote:
mdadm: looking for devices for /dev/md0
mdadm: no recogniseable superblock on /dev/sdd
mdadm: /dev/sdd has no superblock - assembly aborted
This is different than the response received when using the partition numbers (NOTE: you are correct in the assumption that all drives are a single partition using the entire disk).

I'd like to re-assemble this array and save all the data to another array, then re-format this array to insure it is functional and stable. Can you suggest a method for repairing the Superblock on /dev/sdd that will not screw up my data?

TIA for your assistance...


Regards...

TexasMike
 
Old 07-24-2009, 11:09 AM   #4
zeno0771
Member
 
Registered: Jun 2006
Location: Northern IL
Distribution: Arch64
Posts: 106

Rep: Reputation: 19
Yeah, that's usually the next error I get too . I take it, then, that you have this array in mdadm.conf? Anyway, comment out the array in mdadm.conf before restarting; stopping the array just idles it (which is ordinarily a good thing). I seem to remember having to use --zero-superblock for this once but I don't recall if that was before I loaded up the drives with data.

I *just* had this happen last week and I'm looking through my logs, but I'm not finding any magic fix. The only difference is I don't have my array in mdadm.conf; I start it manually to see if anything's gone wrong, so when I restart the machine the array isn't assembled. Again, however, mine's on a separate box so it's rarely restarted.

On another note, with 2 spares you might want to consider RAID 6 instead of 5; tolerates the loss of 2 drives and as we know, the higher the number of drives in an array the more likely a multiple failure will occur.
 
  


Reply

Tags
raid


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
NTFS Partition Problems on HW Raid 5 Array Absolute Zero Linux - Hardware 5 05-17-2009 10:10 PM
Adding an old software-RAID array to a software-RAID installation.. Boot problems GarethM Linux - Hardware 2 05-05-2008 03:16 PM
x86 assembly -- problem w/ syntax for looping over array jrtayloriv Programming 7 02-01-2008 08:46 AM
Problems adding Highpoint 1520 Raid 1 array to working RH9 spifl Linux - Hardware 3 07-16-2005 08:47 AM
problems dual booting win2k / RH71 on a RAID array maskedferret Linux - Software 3 12-02-2001 08:01 PM


All times are GMT -5. The time now is 09:30 PM.

Main Menu
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
identi.ca: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration