Ubuntu – get ‘HDIO_GET_IDENTITY failed’ message when booting with external usb hard drive

I also experienced that issue. But I've found a workaround for this.

My USB drive has first NTFS partition of 430GB (sdg1) followed by Linux partition of 10 GB (sdg2) (all primary). I installed Ubuntu (or afterwards Trisquel) to it and had the same error about unknown filesystem.

It was that grub was unable to "see" Linux partition after such "large" NTFS partition. I don't know the exact limitations of GRUB2, but my 430GB was above it.

Here is the workaround:

1. Install grub to USB HDD with root directory at /dev/sdg1 (NTFS partition). You then will have grub.cfg in /boot/grub/ on that partition.

2. Copy kernel and inirtd image to /boot/ubuntu/ at /dev/sdg1.

3. Change grub.cfg to have root at 'hd0,msdos1' and to load kernel and initrd from /boot/ubuntu/.

Done.

Here is my grub.cfg entry, for example:

menuentry 'Ubuntu' {
    insmod gzio
    insmod part_msdos
    insmod ext2
    set root='hd0,msdos1'
    echo    'Loading Linux'
    linux   /boot/iubuntu/vmlinuz-3.5.0-17-generic root=UUID=erg7659b-ad4c-4f84-9ea0-6e9636768669 ro   quiet splash
    echo    'Loading initial ramdisk ...'
    initrd  /boot/iubuntu/initrd.img-3.5.0-17-generic
}

PS: this workaround won't work with every distro (with ArchBang, for example).

To determine whether the problem is the drive or the enclosure, remove the drive from the enclosure, install it in a desktop with sufficient power and check the smart status.

For a deeper test, you can check every sector of the drive utilizing tools like ddrescue. ddrescue will report error size during the process and you can attempt data recovery at the same time as in: sudo ddrescue /dev/sdb2 /path/to/recovery.image logfile. List the partitions with sudo lsblk or classic fdisk -l.

If you truly have no interest in the data you can force the output file to /dev/null as in:

sudo ddrescue --force /dev/sdc /dev/null logfile 

and you'll still get a report on any error size on stdout

Tested on Ubuntu 14.04 with GNU ddrescue 1.17 as follows inthis short example using /dev/sdb2 (a 1MB swap partition)

$ sudo ddrescue --force /dev/sdb2 /dev/null logfile


GNU ddrescue 1.17
Press Ctrl-C to interrupt
rescued:      1024 B,  errsize:       0 B,  current rate:     1024 B/s
   ipos:         0 B,   errors:       0,    average rate:     1024 B/s
   opos:         0 B,    time since last successful read:       0 s