wiki:TipAndDoc/storage/RAID/rescue/RAID1

Version 3 (modified by mitty, 14 years ago) (diff)

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  1. RAID1
    1. sample RAID1 device
    2. rescue with Knoppix
      1. devices
      2. modprobe
      3. scan devices
      4. method 1
      5. method 2
      6. result
    3. degraded RAID1
      1. devices
      2. modprobe
      3. method 1
      4. method 2
      5. result

RAID1

sample RAID1 device

  • mitty@ubuntu-haa:~$ sudo mdadm -D /dev/md0 
    /dev/md0:
        Version : 00.90
  Creation Time : Thu Mar 24 17:31:36 2011
     Raid Level : raid1
     Array Size : 2047936 (2000.27 MiB 2097.09 MB)
  Used Dev Size : 2047936 (2000.27 MiB 2097.09 MB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 0
    Persistence : Superblock is persistent

    Update Time : Thu Mar 24 21:25:32 2011
          State : clean
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0

           UUID : 32578407:6f33f50b:893cf340:745f5dce (local to host ubuntu-haa)
         Events : 0.34

    Number   Major   Minor   RaidDevice State
       0       8       17        0      active sync   /dev/sdb1
       1       8       33        1      active sync   /dev/sdc1
  • mitty@ubuntu-haa:~$ sudo mdadm --stop /dev/md0 
    mdadm: stopped /dev/md0
  • mitty@ubuntu-haa:~$ sudo mdadm -E /dev/sd[bc]1 
    /dev/sdb1:
          Magic : a92b4efc
        Version : 00.90.00
           UUID : 32578407:6f33f50b:893cf340:745f5dce (local to host ubuntu-haa)
  Creation Time : Thu Mar 24 17:31:36 2011
     Raid Level : raid1
  Used Dev Size : 2047936 (2000.27 MiB 2097.09 MB)
     Array Size : 2047936 (2000.27 MiB 2097.09 MB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 0

    Update Time : Thu Mar 24 21:25:32 2011
          State : clean
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0
       Checksum : e3889399 - correct
         Events : 34


      Number   Major   Minor   RaidDevice State
this     0       8       17        0      active sync   /dev/sdb1

   0     0       8       17        0      active sync   /dev/sdb1
   1     1       8       33        1      active sync   /dev/sdc1
/dev/sdc1:
          Magic : a92b4efc
        Version : 00.90.00
           UUID : 32578407:6f33f50b:893cf340:745f5dce (local to host ubuntu-haa)
  Creation Time : Thu Mar 24 17:31:36 2011
     Raid Level : raid1
  Used Dev Size : 2047936 (2000.27 MiB 2097.09 MB)
     Array Size : 2047936 (2000.27 MiB 2097.09 MB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 0

    Update Time : Thu Mar 24 21:25:32 2011
          State : clean
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0
       Checksum : e38893ab - correct
         Events : 34


      Number   Major   Minor   RaidDevice State
this     1       8       33        1      active sync   /dev/sdc1

   0     0       8       17        0      active sync   /dev/sdb1
   1     1       8       33        1      active sync   /dev/sdc1

rescue with Knoppix

  • root@Knoppix:~# cat /etc/knoppix-version 
    5.3.1 2008-03-26
  • root@Knoppix:~# uname -a 
    Linux Knoppix 2.6.24.4 #2 SMP PREEMPT Tue Mar 25 21:35:28 CET 2008 i686 GNU/Linux

devices

  • root@Knoppix:~# ls -l /dev/sd? 
    brw-rw---- 1 root disk 8,   0 Mar 25  2011 /dev/sda
brw-rw---- 1 root disk 8,  16 Mar 25  2011 /dev/sdb

modprobe

  • root@Knoppix:~# cat /proc/mdstat 
    cat: /proc/mdstat: No such file or directory
  • root@Knoppix:~# modprobe md_mod
  • root@Knoppix:~# cat /proc/mdstat 
    Personalities :
unused devices: <none>

scan devices

  • root@Knoppix:~# mdadm -E /dev/sd* 2>/dev/null 
    /dev/sda1:
          Magic : a92b4efc
        Version : 00.90.00
           UUID : 32578407:6f33f50b:893cf340:745f5dce
  Creation Time : Thu Mar 24 17:31:36 2011
     Raid Level : raid1
  Used Dev Size : 2047936 (2000.27 MiB 2097.09 MB)
     Array Size : 2047936 (2000.27 MiB 2097.09 MB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 0

    Update Time : Thu Mar 24 21:25:32 2011
          State : clean
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0
       Checksum : e3889399 - correct
         Events : 0.34


      Number   Major   Minor   RaidDevice State
this     0       8       17        0      active sync   /dev/sdb1

   0     0       8       17        0      active sync   /dev/sdb1
   1     1       8       33        1      active sync   /dev/sdc1
/dev/sdb1:
          Magic : a92b4efc
        Version : 00.90.00
           UUID : 32578407:6f33f50b:893cf340:745f5dce
  Creation Time : Thu Mar 24 17:31:36 2011
     Raid Level : raid1
  Used Dev Size : 2047936 (2000.27 MiB 2097.09 MB)
     Array Size : 2047936 (2000.27 MiB 2097.09 MB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 0

    Update Time : Thu Mar 24 21:25:32 2011
          State : clean
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0
       Checksum : e38893ab - correct
         Events : 0.34


      Number   Major   Minor   RaidDevice State
this     1       8       33        1      active sync   /dev/sdc1

   0     0       8       17        0      active sync   /dev/sdb1
   1     1       8       33        1      active sync   /dev/sdc1
  • root@Knoppix:~# mdadm -Es 
    ARRAY /dev/md0 level=raid1 num-devices=2 UUID=32578407:6f33f50b:893cf340:745f5dce

method 1

  • root@Knoppix:~# mdadm -A /dev/md0 -u 32578407:6f33f50b:893cf340:745f5dce 
    mdadm: /dev/md0 has been started with 2 drives.
    • 以下のようなエラーが出た場合は、modprobe md_modし忘れている場合がある 
      mdadm: error opening /dev/md0: No such device or address

method 2

  • root@Knoppix:~# mdadm -A /dev/md0 /dev/sd[ab]1 
    mdadm: /dev/md0 has been started with 2 drives.

result

  • root@Knoppix:~# cat /proc/mdstat 
    Personalities : [raid1]
md0 : active raid1 sda1[0] sdb1[1]
      2047936 blocks [2/2] [UU]

unused devices: <none>
  • root@Knoppix:~# mdadm -Ds 
    ARRAY /dev/md0 level=raid1 num-devices=2 UUID=32578407:6f33f50b:893cf340:745f5dce
  • root@Knoppix:~# mdadm -D /dev/md0 
    /dev/md0:
        Version : 00.90.03
  Creation Time : Thu Mar 24 17:31:36 2011
     Raid Level : raid1
     Array Size : 2047936 (2000.27 MiB 2097.09 MB)
  Used Dev Size : 2047936 (2000.27 MiB 2097.09 MB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 0
    Persistence : Superblock is persistent

    Update Time : Thu Mar 24 21:25:32 2011
          State : clean
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0

           UUID : 32578407:6f33f50b:893cf340:745f5dce
         Events : 0.34

    Number   Major   Minor   RaidDevice State
       0       8        1        0      active sync   /dev/sda1
       1       8       17        1      active sync   /dev/sdb1
  • root@Knoppix:~# pvdisplay -C 
      PV         VG    Fmt  Attr PSize PFree
  /dev/md0   vgnfs lvm2 a-   1.94G 1.94G
  • root@Knoppix:~# vgdisplay -C 
      VG    #PV #LV #SN Attr   VSize VFree
  vgnfs   1   0   0 wz--n- 1.94G 1.94G

degraded RAID1

devices

  • root@Knoppix:~# ls -l /dev/sd? 
    brw-rw---- 1 root disk 8,   0 Mar 25  2011 /dev/sda

modprobe

  • root@Knoppix:~# cat /proc/mdstat 
    cat: /proc/mdstat: No such file or directory
  • root@Knoppix:~# modprobe md_mod
  • root@Knoppix:~# cat /proc/mdstat 
    Personalities :
unused devices: <none>
  • root@Knoppix:~# mdadm -E /dev/sda1 
    /dev/sda1:
          Magic : a92b4efc
        Version : 00.90.00
           UUID : 32578407:6f33f50b:893cf340:745f5dce
  Creation Time : Thu Mar 24 17:31:36 2011
     Raid Level : raid1
  Used Dev Size : 2047936 (2000.27 MiB 2097.09 MB)
     Array Size : 2047936 (2000.27 MiB 2097.09 MB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 0

    Update Time : Thu Mar 24 21:25:32 2011
          State : clean
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0
       Checksum : e3889399 - correct
         Events : 0.34


      Number   Major   Minor   RaidDevice State
this     0       8       17        0      active sync   /dev/sdb1

   0     0       8       17        0      active sync   /dev/sdb1
   1     1       8       33        1      active sync   /dev/sdc1
  • root@Knoppix:~# mdadm -Es 
    ARRAY /dev/md0 level=raid1 num-devices=2 UUID=32578407:6f33f50b:893cf340:745f5dce

method 1

  • root@Knoppix:~# mdadm -A /dev/md0 -u 32578407:6f33f50b:893cf340:745f5dce 
    mdadm: /dev/md0 has been started with 1 drive (out of 2).

method 2

  • root@Knoppix:~# mdadm -A /dev/md0 /dev/sda1 
    mdadm: /dev/md0 has been started with 1 drive (out of 2).

result

  • root@Knoppix:~# cat /proc/mdstat 
    Personalities : [raid1]
md0 : active raid1 sda1[0]
      2047936 blocks [2/1] [U_]

unused devices: <none>
  • root@Knoppix:~# mdadm -Ds 
    ARRAY /dev/md0 level=raid1 num-devices=2 UUID=32578407:6f33f50b:893cf340:745f5dce
  • root@Knoppix:~# mdadm -D /dev/md0 
    /dev/md0:
        Version : 00.90.03
  Creation Time : Thu Mar 24 17:31:36 2011
     Raid Level : raid1
     Array Size : 2047936 (2000.27 MiB 2097.09 MB)
  Used Dev Size : 2047936 (2000.27 MiB 2097.09 MB)
   Raid Devices : 2
  Total Devices : 1
Preferred Minor : 0
    Persistence : Superblock is persistent

    Update Time : Thu Mar 24 21:25:32 2011
          State : clean, degraded
 Active Devices : 1
Working Devices : 1
 Failed Devices : 0
  Spare Devices : 0

           UUID : 32578407:6f33f50b:893cf340:745f5dce
         Events : 0.34

    Number   Major   Minor   RaidDevice State
       0       8        1        0      active sync   /dev/sda1
       1       0        0        1      removed