[Bug 48229] Re: Partition table destroyed when resizing NTFS

[Szaka]

Resizing a partition having a filesystem consists of three different
steps:

1. resizing the filesystem (ntfsresize)

2. resizing the partition (libparted)

3. coordinating the above two (gparted)

As being the ntfsresize author, I've investigated well over a hundred
cases in the last four years when resizing went wrong, with different
partitioners (gparted, qtparted, yast, debian-partman, etc). In every
each cases the partition table was corrupted what ntfsresize doesn't
even read.

The explanation and the solution is very simple. Parted uses a heuristic
how to set the geometry, no matter if it's asked to do or not. Sometimes
or often (depending on how the kernel changes the relevant ioctl
semantic) this makes Windows unbootable (bootloader can't access the
entire volume) or the partition inaccessible (partition start is
adjusted to a fictive cylinder boundary).

It's very easy to confirm this: don't use any partitioner, only
ntfsresize then boot Windows. It will work fine. The partition remains
the old size but the NTFS size will be the new one.

Here I've summarized how to troubleshoot partitiontable corruptions.
http://mlf.linux.rulez.org/mlf/ezaz/ntfsresize.html#troubleshoot

The problem is filesystem independent and Parted never worked correctly.
Linux boot doesn't care about the legacy disk geometry thus this issue
isn't visible with Linux filesystems unless the partition start got
shifted (the filesystem "disappears").

-- 
Partition table destroyed when resizing NTFS
https://launchpad.net/bugs/48229