[Bug 1245147] Re: Ubuntu 13.10 does not boot from USB stick 3.0

[Phillip Susi]

The MBR contains the partition table and initial boot code the bios
loads, which is one part of grub.  That part loads the grub core, which
can be a file in /boot/grub, but since files tend to move around and
that would break the MBR's ability to find it ( since it is so small,
the location of the file has to be hard coded into the MBR ), it is
instead preferred to embed the core image in the sectors between the MBR
and the first partition, so it won't move around or be replaced by
accident.

A /boot partition simply contains everything in the /boot directory,
which includes the kernels and /boot/grub, which contains grub's config
file and modules that the core loads.

Creating a new partition with gparted should make it start at sector
2048, are you sure you deleted it and recreated it ( not just format it
)?  Maybe you used an ancient version of gparted?

32 sectors is not enough space for the grub core image, which these days
needs something like 60-70.  It should work the other way though, so if
you got the key to boot in another machine, then it is probably fine.

Can you try holding down shift when booting to see if you get the grub
menu?

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https://bugs.launchpad.net/bugs/1245147

Title:
  Ubuntu 13.10 does not boot from USB stick 3.0

Status in “grub2” package in Ubuntu:
  Incomplete

Bug description:
  I have tried to perform a normal installation of ubuntu 13.10 on a
  usb3.0 stick sandisk 16Gb, formatted ext4.

  I do not how to provide you more information since grub does not even
  start and a violet screen hangs. I was suspecting a corruption of the
  usb mbr and I have tried updating directly the grub the I have on the
  hard disk used by ubuntu 13.04 and windows 7 with the key plugged in
  but again just violet screen and everything hangs.

  If I create a live usb in fat32 I do not have any problem. Could you
  please verify if there is a bug in ext4?

  Before on the same usb I had Ubuntu 13.04 but in UEFI mode since I was
  using a netbook UEFI. Now for sure I have a bios legacy and for this
  reason I have removed everything to reinstall ubuntu 13.10 in the mbr.

  The usb key has been formatted in gparted recreating again the
  partition table in msdos as follow:

  Le voci nella tabella delle partizioni non sono nello stesso ordine
  del disco.

  Disk /dev/sdb: 15.5 GB, 15504900096 bytes
  64 testine, 32 settori/tracce, 14786 cilindri, totale 30283008 settori
  Unità = settori di 1 * 512 = 512 byte
  Sector size (logical/physical): 512 bytes / 512 bytes
  I/O size (minimum/optimal): 512 bytes / 512 bytes
  Identificativo disco: 0x00018829

  Dispositivo Boot      Start         End      Blocks   Id  System
  /dev/sdb1   *        2048    13632907     6815430   83  Linux
  /dev/sdb2        13635582    30281727     8323073    5  Esteso
  /dev/sdb5        13635584    14684159      524288   82  Linux swap / Solaris
  /dev/sdb6        14686208    30281727     7797760    7  HPFS/NTFS/exFAT

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