[Bug 556167] Re: vmbuilder uses parted to create disk images, which leads to broken sector counts (cannot use grub2 on disk images created by vmbuilder/parted)

[Phillip Susi]

Parted defaults to leaving the first 1 MB of the disk empty these days,
regardless of the cylinder size.  I just tested it by creating a 1 gb
file and having parted mklabel msdos, then mkpart using 0% and 100% as
the start and end positions, and the partition starts at sector 2048
even though the sector count is 32.

Can you describe how to reproduce the results you describe with parted?


** Changed in: parted (Ubuntu)
       Status: Confirmed => Incomplete

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to parted in Ubuntu.
https://bugs.launchpad.net/bugs/556167

Title:
  vmbuilder uses parted to create disk images, which leads to broken
  sector counts (cannot use grub2 on disk images created by
  vmbuilder/parted)

Status in “parted” package in Ubuntu:
  Incomplete
Status in “vm-builder” package in Ubuntu:
  Confirmed

Bug description:
  parted uses a fixed sector count of "32" when writing partitions to a
  non-block device.  (See init_file() via linux_new() in
  libparted/arch/linux.c)  As a result, the track size of disks created
  with vmbuilder is 32 sectors, not the generally expected 63 sectors
  (used with LBA mode).  This means that the "embedding region" between
  the end of the MBR and the start of partition 1 is half the "normal"
  size, and grub2 will not install.

  /usr/sbin/grub-setup: warn: Your embedding area is unusually small.
  core.img won't fit in it..

  Fastest solution I see is to use an environment override as already
  done in init_file() for sector size.  Perhaps PARTED_SECTORS?  And
  then set this to 63 when calling parted from vm-builder.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/parted/+bug/556167/+subscriptions