LinuxQuestions.org
View the Most Wanted LQ Wiki articles.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Software
User Name
Password
Linux - Software This forum is for Software issues.
Having a problem installing a new program? Want to know which application is best for the job? Post your question in this forum.

Notices

Reply
 
Search this Thread
Old 04-15-2011, 06:27 AM   #1
rrije
Member
 
Registered: Jul 2010
Distribution: openSUSE 11.4
Posts: 32

Rep: Reputation: Disabled
Moving software RAID0 from openSUSE to Slackware


Hi,

I have a software RAID0 consisting of 2 disks on a machine running openSUSE. RAID was created with help of YAST's Partitioner feature. Now I'm planning to replace Suse with Slackware, so I've run a simulation in virtualbox, creating RAID exactly the same way as it was created on "real" machine, installing Slackware and trying to reassemble it with mdadm.

This is where trouble and confusion begin.
Code:
root@slackraid:~# mdadm --assemble /dev/md0 /dev/sdb1 /dev/sdc1
mdadm: no recogniseable superblock on /dev/sdb1
mdadm: /dev/sdb1 has no superblock - assembly aborted
Then I do a little examination of devices involved:
Code:
root@slackraid:~# mdadm --query /dev/sdb1
/dev/sdb1: is an md device which is not active

root@slackraid:~# mdadm --query /dev/sdc1
/dev/sdc1: is not an md array
/dev/sdc1: device 1 in 2 device unknown raid0 array.  Use mdadm --examine for more detail.
Why would the same command give different results for identical drives?
Code:
root@slackraid:~# mdadm --examine /dev/sdb1
mdadm: No md superblock detected on /dev/sdb1.

root@slackraid:~# mdadm --examine /dev/sdc1
/dev/sdc1:
          Magic : a92b4efc
        Version : 1.0
    Feature Map : 0x0
     Array UUID : 763b9c53:1adbffe0:29d4db6f:19756de5
           Name : HW-OPENSUSE:0
  Creation Time : Thu Apr 14 22:16:48 2011
     Raid Level : raid0
   Raid Devices : 2

 Avail Dev Size : 2121712 (1036.17 MiB 1086.32 MB)
  Used Dev Size : 0
   Super Offset : 2121712 sectors
          State : clean
    Device UUID : b90dbad2:1c87bd82:2d71a991:b8366fb8

    Update Time : Thu Apr 14 22:16:48 2011
       Checksum : 4af21230 - correct
         Events : 0

     Chunk Size : 128K

    Array Slot : 1 (0, 1)
   Array State : uU
How come /dev/sdb1 is an inactive md device, but has no superblock, and /dev/sdc1 has correct superblock, but not is an md device?

Can someone explain this to me? Thanks in advance.
 
Old 04-18-2011, 12:07 PM   #2
jason_not
Member
 
Registered: Aug 2010
Location: Beaverton, Oregon, USA
Distribution: Pfsense, Ubuntu, Centos, Fedora, Redhat, Scientfic, MacOS
Posts: 76

Rep: Reputation: 19
Hello,

My thought is to check if the superblock on /dev/sdb1 got corrupted. I believe under ext[234] filesystems the superblock is copied to redundant blocks on the disk. I don't know if it's the same with a software raid array.

--jason
 
  


Reply


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
[SOLVED] Moving software RAID5 set from OpenSuse to Ubuntu? gregmcc Linux - Software 5 01-02-2011 10:30 AM
Moving Raid0 on Redhat Linux Ashron Red Hat 0 07-10-2004 07:25 PM
Software RAID0 + Slack9.1 Aphex Slackware 0 11-02-2003 02:14 AM
Trouble with HD and software raid0 RC_ Linux - Hardware 0 08-07-2003 12:28 AM
Software RAID0 mess up, help! Devoras Linux - General 1 01-01-2003 11:20 PM


All times are GMT -5. The time now is 03:22 AM.

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