Unable to mount NTFS partitions on a drive which is part of an Intel isw raid (fakeraid)

But as soon as I tried to mount /dev/sdd3, the operation failed:

mintp ~ # mount /dev/sdd3 /mnt
mount: special device /dev/sdd3 does not exist

And yes, the relevant NTFS mount tools (ntfs-3g) are installed. For the sake of article completeness:

mintp ~ # dpkg -l|grep -i ntfs
ii  ntfs-3g    1:2015.3.14AR.1-1ubuntu0.3  amd64  read/write NTFS driver for FUSE
ii  syslinux   3:6.03+dfsg-11ubuntu1       amd64  collection of bootloaders (DOS FAT and NTFS bootloader)

Intel fakeraid is still active on the drive

Checking the current drive information using blkid revealed that this drive is still "introducing" itself as a member of an ISW raid:

mintp ~ # blkid | grep sdd
/dev/sdd: TYPE="isw_raid_member"

I've had a kind of similar issue in the past with Intel ISW drives, described in article Mount a HDD which is a member in Intel Raid to back up data, however back then I got another error message (device or resource busy) when I tried to mount the partition. So there must be something else going on. The commands (dmraid) from this older article unfortunately didn't work.

Even trying to manually enable the ISW raid did not work:

mintp ~ # dmraid -ay
ERROR: isw: Could not find disk /dev/sdd in the metadata
no raid disks

On the other hand, an isw controller could not be found in /dev/mapper/ either (which is needed to talk to the partitions behind the ISW raid):

mintp ~ # ls /dev/mapper/*
/dev/mapper/control

Additional information about the Intel ISW Raid could also be seen using mdadm:

mintp ~ # mdadm -E /dev/sdd
mdmon: /dev/sdd is not attached to Intel(R) RAID controller.
mdmon: /dev/sdd is not attached to Intel(R) RAID controller.
/dev/sdd:
          Magic : Intel Raid ISM Cfg Sig.
        Version : 1.1.00
    Orig Family : 174b6efe
         Family : 174b6fc2
     Generation : 0063e318
     Attributes : All supported
           UUID : 0b24ad7f:9b251541:a98a3748:f6333faa
       Checksum : 3abd3e46 correct
    MPB Sectors : 1
          Disks : 2
   RAID Devices : 1

[RAID1]:
           UUID : aaa62640:f0d57fc8:6c097c8f:547b9c8f
     RAID Level : 1
        Members : 2
          Slots : [UU]
    Failed disk : none
      This Slot : ?
     Array Size : 1465143296 (698.63 GiB 750.15 GB)
   Per Dev Size : 1465143560 (698.63 GiB 750.15 GB)
  Sector Offset : 0
    Num Stripes : 5723216
     Chunk Size : 64 KiB
       Reserved : 0
  Migrate State : idle
      Map State : normal
    Dirty State : clean

  Disk00 Serial : 6VPCFBB5
          State : active
             Id : 00010000
    Usable Size : 1465142862 (698.63 GiB 750.15 GB)

  Disk01 Serial : 9VPBDF78
          State : active
             Id : 00000000
    Usable Size : 1465142862 (698.63 GiB 750.15 GB)

It's actually mdadm to blame!

Just when I thought to give up and attach the drive to a Windows machine, I finally came across a thread in the Fedora forums which a very interesting post from user lzap:

Seems mdadm tried to build an array for me

I checked the mdadm status and indeed, there was a new raid md127 showing up, using the SDD drive!

mintp ~ # cat /proc/mdstat
Personalities : [raid1] [linear] [multipath] [raid0] [raid6] [raid5] [raid4] [raid10]
md127 : inactive sdd[0](S)
      3153 blocks super external:imsm

md0 : active raid1 sda1[0] sdb1[1]
      484060160 blocks super 1.2 [2/2] [UU]
      bitmap: 4/4 pages [16KB], 65536KB chunk

md1 : active raid1 sdb2[1] sda2[0]
      4190208 blocks super 1.2 [2/2] [UU]

unused devices:

Disabled this raid device followed by erasing the drive's superblock:

mintp ~ # mdadm --stop /dev/md127
mdadm: stopped /dev/md127

mintp ~ # mdadm --zero-superblock /dev/sdd
mdmon: /dev/sdd is not attached to Intel(R) RAID controller.
mdmon: /dev/sdd is not attached to Intel(R) RAID controller.

And finally, blkid showed the partition uuid's:

mintp ~ # blkid|grep sdd
/dev/sdd1: LABEL="System Reserved" UUID="CEAABB7CAABB601F" TYPE="ntfs" PARTUUID="6cef09fe-01"
/dev/sdd2: UUID="101EC9371EC9171E" TYPE="ntfs" PARTUUID="6cef09fe-02"
/dev/sdd3: UUID="E646DD2A46DCFBED" TYPE="ntfs" PARTUUID="6cef09fe-03"

And as you may guess, mounting the data partition finally worked:

mintp ~ # mount -o ro /dev/sdd3 /mnt
mintp ~ # df -h /mnt
Filesystem      Size  Used Avail Use% Mounted on
/dev/sdd3       631G  508G  123G  81% /mnt