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I've been running Ubuntu from my flash drive for a while now, but due to the frequent read/write feature of the journaling system, it was excessively slow. I read about how it might be this slow running Ubuntu on my ext3/ext4 file system on my flash drive, I decided to reinstall the whole thing with ext2 instead, and trouble ensued.

It was very perculiar that it doesn't seem to have any problem running the newly installed system the first time after installation following the restart option the installer offers, but it will never successfully boot ever again. Here's what I run into instead of my Ununtu system:

ata_id[259]: HDID_GET_IDENTITY failed for '/dev/sdb': Invalid argument

Gave up waiting for root device.  Common problems:
 - Boot rags (cat /proc/cmdline)
   - Check rootdelay= (did the system wait long enough?)
   - Check root= (did the system wait for the right device?)
 - Missing modules (cat /proc/modules; ls /dev)
ALERT!  /dev/sdc1 does not exist. Dropping to a shell!

BusyBox v1.19.3 (Ubuntu 1:1.19.3-7ubuntu1) built-in shell (ash)
Enter 'help' for a list of built-in commands.

(initramfs) cat /proc/cmdline
BOOT_IMAGE=/boot/vmlinuz-3.5.0-17-generic root=/dev/sdc1 ro quite splash

I suspect the problem is grub points at /dev/sdc1, which is my flash drive for boot sequence, but somehow my computer failed to find it. Can anyone help me with this?

share|improve this question
How did you add the menuentry to boot from the flash drive to GRUB? – minerz029 Sep 12 '13 at 12:07
I didn't. It's exactly like when I install Ubuntu side-by-side with my Windows 7, only when choosing "Ubuntu" at the stage I would eventually boot into my usb flash drive instead of my partition on my hard drive. – alxyzc Sep 12 '13 at 12:14
Try running sudo update-grub and trying again – minerz029 Sep 12 '13 at 12:17
I don't think I can run Ubuntu commands in either ash or grub prompt since I'm yet to boot into my Ubuntu system. – alxyzc Sep 12 '13 at 12:19

Your GRUB should not point directly at /dev/sdc1 as this can change if you plug in or remove more USB drives (or other drives), instead, use a UUID to point to the partition.

It might work, though if you drop to GRUB command line (press c at GRUB menu), then execute the command reboot and try booting from your USB again.

share|improve this answer
I think that might be the reason. I had the live usb connected for installation which I had to remove afterwards and is no longer there. How exactly do I point GRUB to my flash drive with my UUID? – alxyzc Sep 12 '13 at 12:21

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