Moved disks to a RAID controller; can't bring back the software RAID5

    • OMV 1.0
    • Resolved

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    • Moved disks to a RAID controller; can't bring back the software RAID5

      Hiya,

      I have 4 drives of 2TB, previously connected directly to the motherboard SATA controller and configured in a RAID5 matrix under OMV. Recently I purchased a HP P410 SAS/SATA RAID controller for some extra kick. Today I connected the disks to the controller and ran into trouble: I can't bring up the RAID5 matrix for an unknown reason.

      The controller is configured with each drive in its own array and a single logical drive. Basically, it bypasses any built-in RAID functionality and exposes the disks as JBOD to the operating system. They just appear with a different name - instead of seeing their model, firmware etc. now I see "Logical volume" for all as Model.

      Here's what I'm getting:

      mdadm --assemble /dev/md127 /dev/sd[abcd] --verbose --force
      mdadm: looking for devices for /dev/md127
      mdadm: /dev/sda is identified as a member of /dev/md127, slot 2.
      mdadm: /dev/sdb is identified as a member of /dev/md127, slot 1.
      mdadm: /dev/sdc is identified as a member of /dev/md127, slot 0.
      mdadm: /dev/sdd is identified as a member of /dev/md127, slot 3.
      mdadm: failed to add /dev/sdb to /dev/md127: Invalid argument
      mdadm: failed to add /dev/sda to /dev/md127: Invalid argument
      mdadm: failed to add /dev/sdd to /dev/md127: Invalid argument
      mdadm: failed to add /dev/sdc to /dev/md127: Invalid argument
      mdadm: failed to RUN_ARRAY /dev/md127: Invalid argument


      If I look in the system log, I get the following:

      Nov 9 22:23:57 openmediavault kernel: [34998.542934] md: md127 stopped.
      Nov 9 22:23:57 openmediavault kernel: [34998.553682] md: sdb does not have a valid v1.2 superblock, not importing!
      Nov 9 22:23:57 openmediavault kernel: [34998.553719] md: md_import_device returned -22
      Nov 9 22:23:57 openmediavault kernel: [34998.554317] md: sda does not have a valid v1.2 superblock, not importing!
      Nov 9 22:23:57 openmediavault kernel: [34998.554353] md: md_import_device returned -22
      Nov 9 22:23:57 openmediavault kernel: [34998.555458] md: sdd does not have a valid v1.2 superblock, not importing!
      Nov 9 22:23:57 openmediavault kernel: [34998.555494] md: md_import_device returned -22
      Nov 9 22:23:57 openmediavault kernel: [34998.557131] md: sdc does not have a valid v1.2 superblock, not importing!
      Nov 9 22:23:57 openmediavault kernel: [34998.557168] md: md_import_device returned -22


      I'm baffled, as I can check each drive with mdadm, but can't bring up the array. Any ideas, please?

      Here are some other results:

      blkid
      /dev/sda: UUID="88e0c6ad-c867-07dc-4db9-c4d4c8c2faa6" UUID_SUB="212abc31-f6ba-f282-c10a-fdcfeedb489f" LABEL="openmediavault:Storage" TYPE="linux_raid_member"
      /dev/sdb: UUID="88e0c6ad-c867-07dc-4db9-c4d4c8c2faa6" UUID_SUB="ef380a3b-8a8a-76d1-1886-b090946d5e7e" LABEL="openmediavault:Storage" TYPE="linux_raid_member"
      /dev/sdc: UUID="88e0c6ad-c867-07dc-4db9-c4d4c8c2faa6" UUID_SUB="82dbfa20-73b3-302a-b8fb-9ddafb554983" LABEL="openmediavault:Storage" TYPE="linux_raid_member"
      /dev/sdd: UUID="88e0c6ad-c867-07dc-4db9-c4d4c8c2faa6" UUID_SUB="7627ad4d-87bd-7f76-2094-a4f1973fe32c" LABEL="openmediavault:Storage" TYPE="linux_raid_member"
      /dev/sdh1: UUID="cc47e1e0-b1ee-4e49-aa7c-d28581c68817" TYPE="ext4"
      /dev/sdh5: UUID="ed1f5117-4fe9-4b88-8137-fc20a06e9ade" TYPE="swap"


      cat /proc/mdstat
      Personalities :
      unused devices: <none>


      mdadm --examine /dev/sd[a-d]
      /dev/sda:
      Magic : a92b4efc
      Version : 1.2
      Feature Map : 0x0
      Array UUID : 88e0c6ad:c86707dc:4db9c4d4:c8c2faa6
      Name : openmediavault:Storage (local to host openmediavault)
      Creation Time : Wed Aug 8 03:13:00 2012
      Raid Level : raid5
      Raid Devices : 4

      Avail Dev Size : 3907025072 (1863.01 GiB 2000.40 GB)
      Array Size : 5860535808 (5589.04 GiB 6001.19 GB)
      Used Dev Size : 3907023872 (1863.01 GiB 2000.40 GB)
      Data Offset : 4096 sectors
      Super Offset : 8 sectors
      State : clean
      Device UUID : 212abc31:f6baf282:c10afdcf:eedb489f

      Update Time : Sun Nov 9 10:04:22 2014
      Checksum : 4a0e4b27 - correct
      Events : 1492

      Layout : left-symmetric
      Chunk Size : 512K

      Device Role : Active device 2
      Array State : AAAA ('A' == active, '.' == missing)
      /dev/sdb:
      Magic : a92b4efc
      Version : 1.2
      Feature Map : 0x0
      Array UUID : 88e0c6ad:c86707dc:4db9c4d4:c8c2faa6
      Name : openmediavault:Storage (local to host openmediavault)
      Creation Time : Wed Aug 8 03:13:00 2012
      Raid Level : raid5
      Raid Devices : 4

      Avail Dev Size : 3907027120 (1863.02 GiB 2000.40 GB)
      Array Size : 5860535808 (5589.04 GiB 6001.19 GB)
      Used Dev Size : 3907023872 (1863.01 GiB 2000.40 GB)
      Data Offset : 2048 sectors
      Super Offset : 8 sectors
      State : clean
      Device UUID : ef380a3b:8a8a76d1:1886b090:946d5e7e

      Update Time : Sun Nov 9 10:04:22 2014
      Checksum : 41a93683 - correct
      Events : 1492

      Layout : left-symmetric
      Chunk Size : 512K

      Device Role : Active device 1
      Array State : AAAA ('A' == active, '.' == missing)
      /dev/sdc:
      Magic : a92b4efc
      Version : 1.2
      Feature Map : 0x0
      Array UUID : 88e0c6ad:c86707dc:4db9c4d4:c8c2faa6
      Name : openmediavault:Storage (local to host openmediavault)
      Creation Time : Wed Aug 8 03:13:00 2012
      Raid Level : raid5
      Raid Devices : 4

      Avail Dev Size : 3907027120 (1863.02 GiB 2000.40 GB)
      Array Size : 5860535808 (5589.04 GiB 6001.19 GB)
      Used Dev Size : 3907023872 (1863.01 GiB 2000.40 GB)
      Data Offset : 2048 sectors
      Super Offset : 8 sectors
      State : clean
      Device UUID : 82dbfa20:73b3302a:b8fb9dda:fb554983

      Update Time : Sun Nov 9 10:04:22 2014
      Checksum : cf2c6004 - correct
      Events : 1492

      Layout : left-symmetric
      Chunk Size : 512K

      Device Role : Active device 0
      Array State : AAAA ('A' == active, '.' == missing)
      /dev/sdd:
      Magic : a92b4efc
      Version : 1.2
      Feature Map : 0x0
      Array UUID : 88e0c6ad:c86707dc:4db9c4d4:c8c2faa6
      Name : openmediavault:Storage (local to host openmediavault)
      Creation Time : Wed Aug 8 03:13:00 2012
      Raid Level : raid5
      Raid Devices : 4

      Avail Dev Size : 3907027120 (1863.02 GiB 2000.40 GB)
      Array Size : 5860535808 (5589.04 GiB 6001.19 GB)
      Used Dev Size : 3907023872 (1863.01 GiB 2000.40 GB)
      Data Offset : 2048 sectors
      Super Offset : 8 sectors
      State : clean
      Device UUID : 7627ad4d:87bd7f76:2094a4f1:973fe32c

      Update Time : Sun Nov 9 10:04:22 2014
      Checksum : 8ce3814 - correct
      Events : 1492

      Layout : left-symmetric
      Chunk Size : 512K

      Device Role : Active device 3
      Array State : AAAA ('A' == active, '.' == missing)
    • Welp, I think I can mark this as "Solved" by applying the workaround above. Currently the 4 disks are connected back to the motherboard built-in SATA controller, software RAID working fine, and transferring data to other drives connected to the hardware RAID card. The sustained 70 MB/s copying speed is a lot better than 16 MB/s when backup disks were connected in a USB(2) external rack. Plus, the partitioning of those disks somehow messed up the partition table, so the backups were not actually retrievable :) So much for trusting USB racks.

      Tonight's fun: after all data is backed up, move the 4 disks to the RAID card and set up a RAID5 there. It has a specialized CPU for accelerating this, dedicated 512MB of ECC RAM, battery backup and a plethora of built-in tools for early identification and recovery from failures. Software RAID might be "free", but when a server-grade hardware RAID controller with all the bells and whistles is under €150... :)