Arch Linux

PierreR

Member

Registered: 2008-11-10

Posts: 58

[Solved] Grub boot partition with external usb HD

Hi,

I have a specific connector HD to USB that allows me to use an old internal HD from a broken computer as an external backup drive.

Mounting the drive is no problem inside any linux OS.

Yesterday, I have tried to install arch on it in order to directly boot it as an external drive (usb port). Unfortunately after a (reformat all standard) installation it does not want to boot up.

The drive has been recognized as /dev/sdb by the life CD so Grub tries to boot it as "hd(1,0)". [The boot partition is the first one].

I then got an error 17.

I have tried geometry (hd0) on the grub command line and I do see my partition scheme there. If I tried "find" it does give me "hd0". So it  makes me believe I should use "hd(0,0)" instead of "hd(1,0)".

If I tried that, it goes further but failed miserably because it cannot find the uuid drive. If I check in the "good luck prompt (ramfs)", I can see I am on the wrong drive (the internal one).

So in Grub the external drive is hd0 but if I go on the boot process I am now on the internal drive ??

I am wondering now if all this mess is not caused by the HD/USB adapter.

I even tried to boot it using the grub2 of the internal drive. It then tries /dev/sdb (hd1) which is not even a device yet (??)

I am lost ...

Any help welcomed.

Thanks

Cheers,

Last edited by PierreR (2011-06-19 07:29:46)

MoonSwan

Member

From: Great White North

Registered: 2008-01-23

Posts: 881

Re: [Solved] Grub boot partition with external usb HD

I've had this problem and the solution was fairly easy:  Go into the computer's bios and locate in there the order of the drives or external device's boot order.  So for example, currently my desktop will try to boot up a CDRom or a USB flash device first; if it finds neither has an OS it will then try to boot up my Arch on my *internal* drive.

You should probably try that and if you still don't succeed then post back.

PierreR

Member

Registered: 2008-11-10

Posts: 58

Re: [Solved] Grub boot partition with external usb HD

I have probably found out what my problem is ...
I guess because it is an USB port, I do need to edit "/etc/mkinitcpio.conf" in order to add "usb" in the HOOKS. And yes, hd(0,0) is the right grub setting.

MoonSwan

Member

From: Great White North

Registered: 2008-01-23

Posts: 881

Re: [Solved] Grub boot partition with external usb HD

Nifty!  Glad you figured it out. 

Please mark as solved.