Ubuntu Installer borks up partitions?

[Sander Smeenk]

Hi,

I find that whenever i use the Ubuntu (Network/PXE) Installer and go
with the 'Guided, use Entire Disk with LVM'-partitioning choice, i end
up with a partition layout which seems to prevent me from ever expanding
these partitions because fdisk-tools dont understand it or refuse to
(re)create it.

For example, after install the 'fdisk -l' output looks like:
|   Device Boot      Start         End      Blocks   Id  System
|/dev/vda1   *        2048      499711      248832   83  Linux
|/dev/vda2          501758   104855551    52176897    5  Extended
|/dev/vda5          501760   104855551    52176896   8e  Linux LVM

I now wish to extend the vda2 and vda5 partitions, so i proceed in
removing the current layout and (trying to) create an identical one
with a differend 'End' or 'Last sector':
| Command (m for help): d
| Partition number (1-5): 5
| Command (m for help): d
| Partition number (1-5): 2
| Command (m for help): n
| Partition type Select (default p): e
| Partition number (1-4, default 2): 2
| First sector (499712-207257599, default 499712): 501758

This is already peculiar as fdisk proposes 499712, which would indeed
be the next sector, but it was 501758 as shown in the 'fdisk -l' output
above. So, i use 501758 and continue:
| Last sector, +sectors or +size{K,M,G} (501758-207257599, default 207257599): 
| Using default value 207257599

Okay. The 'p'rint current partitions now matches the original up to vda2
with the same Start and a higher End sector. So i proceed:
| Command (m for help): n
| Partition type Select (default p): l
| Adding logical partition 5
| First sector (503806-207257599, default 503806): 501760
| Value out of range.
| First sector (503806-207257599, default 503806): 

And there i'm stuck.

Other fdisk tools like sfdisk complain about the Ubuntu Installer
provided partition layout having an 'extended partition [that] does
not start at a cylinder boundary'. Its output is:
| sfdisk: Warning: extended partition does not start at a cylinder boundary.
|    Device Boot Start     End   #cyls    #blocks   Id  System
| /dev/vda1   *      2+    495-    494-    248832   83  Linux
|         start: (c,h,s) expected (2,0,33) found (0,32,33)
|         end: (c,h,s) expected (495,11,59) found (31,26,59)
| /dev/vda2        497+ 104023- 103526-  52176897    5  Extended
|         start: (c,h,s) expected (497,12,27) found (31,59,27)
|         end: (c,h,s) expected (1023,15,63) found (1023,254,63)
| /dev/vda3          0       -       0          0    0  Empty
| /dev/vda4          0       -       0          0    0  Empty
| /dev/vda5        497+ 104023- 103526-  52176896   8e  Linux LVM
|         start: (c,h,s) expected (497,12,29) found (31,59,29)
|         end: (c,h,s) expected (1023,15,63) found (1023,254,63)

Should i file a bug? If so, what would i file that on?

-Sndr.
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