How do I check if an USB drive is bootable?

Question

I just created an USB drive and would like to check if it's correctly bootable without rebooting my actual computer. How should I do?

lolesque · Accepted Answer · 2015-10-14T12:46:46.810

7

Under Linux, you have to know which device path got the drive with for example with dmesg | tail after insertion, let's assume it's /dev/sdb.

Qemu

sudo qemu -hda /dev/sdb or sudo qemu-system-x86_64 -hda /dev/sdb for 64 bits.

VirtualBox

VBoxManage internalcommands createrawvmdk -filename ~/usb.vmdk -rawdisk /dev/sdb
sudo chmod 666 /dev/sdb*

then add ~/usb.vmdk as a disk in a VM and boot on it

Don't hesitate to add other ways to do.

edited Oct 14 '15 at 12:46

answered Sep 05 '12 at 15:22

lolesque

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Note: qemu can wrongly finish on "fatal authentication error", then "init: respawning too fast: disabled for 5 minutes." but it doesn't happen on real machines. – lolesque Jan 30 '13 at 15:39
You can also use the windows version of QEmu, if you only have windows. – Jeremy Salwen Feb 20 '14 at 09:09
Not sure why but the 'qemu' command doesn't work for me, I need: qemu-system-x86_64 or qemu-system-i386 depending on whether you want to boot a 64-bit or 32-bit VM (hint: you want 64-bit) – Paul Jun 30 '19 at 17:08

score 7 · Answer 2 · answered Mar 05 '13 at 18:21

While it won't show if the stuff on the filesystem is capable of handling the whole boot thing you can check the boot flag with fdisk -l <drive> from a shell on a reasonably good *nix. (Which essentially tells the bios if it should try to boot the thingie or not.)

How do I check if an USB drive is bootable?

2 Answers2

Qemu

VirtualBox