Bug 6080

Summary: diskdrake skips 2048k between each partition in KVM guest
Product: Mageia Reporter: AL13N <alien>
Component: RPM PackagesAssignee: Thierry Vignaud <thierry.vignaud>
Status: RESOLVED OLD QA Contact:
Severity: major    
Priority: Normal CC: davidwhodgins, stormi-mageia
Version: 2Keywords: Triaged
Target Milestone: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Source RPM: drakxtools-14.21-1.mga2.src.rpm CVE:
Status comment:

Description AL13N 2012-05-25 11:18:23 CEST
Description of problem:
In basic, mode, when creating a partition, that partition (even though startsector 1) skips 2048k.

if the disk is small enough (40GB), you can even see the gaps before each partition.

Steps to Reproduce:
1. have a mageia KVM host
2. create a new mageia KVM guest (disk will become /dev/vda )
3. custom partitioning
4. create partition
5. start sector = 1
6. see the gap before the partition, you can even click on it, while it says 0bytes, it's actually 2kB lost.

while this isn't the end of the world, it's not really good.
Comment 1 Dave Hodgins 2012-05-25 23:17:32 CEST
Please attach the output of
sfdisk -l -uS -x /dev/vda >sfdisk.txt

Also, are you using diskdrake in normal or expert mode?

CC: (none) => davidwhodgins

Comment 2 AL13N 2012-05-26 00:18:28 CEST
normal

[root@builder ~]# sfdisk -l -uS -x /dev/vda

Disk /dev/vda: 83220 cylinders, 16 heads, 63 sectors/track
sfdisk: Warning: extended partition does not start at a cylinder boundary.
DOS and Linux will interpret the contents differently.

Units = sectors of 512 bytes, counting from 0

   Device Boot    Start       End   #sectors  Id  System
/dev/vda1   *      2048    236879     234832  83  Linux
/dev/vda2        239589  83885759   83646171   5  Extended
/dev/vda3             0         -          0   0  Empty
/dev/vda4             0         -          0   0  Empty

/dev/vda5        239616   8743391    8503776  82  Linux swap / Solaris
    -           8744960  83885759   75140800   5  Extended
    -            239589    239588          0   0  Empty
    -            239589    239588          0   0  Empty

/dev/vda6       8747008  83885759   75138752  83  Linux
    -           8744960   8744959          0   0  Empty
    -           8744960   8744959          0   0  Empty
    -           8744960   8744959          0   0  Empty
Comment 3 Dave Hodgins 2012-05-26 02:33:20 CEST
The program diskdrake, like gparted and most partitioning tools have been
changed to align partitions on 1 MB boundaries, by default, to avoid
partition alignment problems on devices like advanced format, ssd and
flash drives, so there should be gaps, as 2048 sectors are reserved for
the mbr+bootloader at the start of the drive, and each extended partition
will reserve 2048 sectors for the partition table for that part of the
extended partition table chain.

However, even given that, the numbers do not look correct to me.  As diskdrake
is being run in normal mode, all of the sector start and number of sectors
should be multiples of 2048.

The vda1 partition starts at 1 MB into the drive, as expected.

The vda1 partition has a size of 114.6640625 MB.

The vda2 partition (the partition table associated with vda5) starts at 116.986816406 MB

The vda5 partition starts at 117 MB.

The extended partition table associated with vda6 starts at 4,270 MB.

The vda6 partition starts at 4,271 MB.

So all of the actual filesystem partitions are correctly aligned on 1 MB boundaries,
I'm surprised that the first partition is not an even number of megabytes, and
the extended partition is not aligned on a MB boundary.

I don't consider this a bug, as all filesystem partitions are being correctly
aligned on 2048 sector boundaries, but I would like to have the maintainer
explain why diskdrake is setting the size of the first partition and the start
of the extended partition such that they are not multiples of 2048 sectors.

Source RPM: diskdrake => drakxtools-14.21-1.mga2.src.rpm

Comment 4 AL13N 2012-05-26 08:22:14 CEST
i know it's been changed, but i think this was because of 1k sized sectors and cylinder boundaries. besides which, the other partitions are more than 1M in between. (3710 sectors and 4000+ sectors)

normally, the first partition starts (exceptionally) at 63 sectors (head 1 instead of head 0).

in any case, diskdrake shows clickable spaces before each partition, which is definately a bug.

also the partitions should be filled to end on the same boundary after all.

so, i see definately some bugs, in whatever way you look at it.
Comment 5 Samuel Verschelde 2013-08-28 14:56:24 CEST
Assigning to maintainer.

Is that bug also true in Mageia 3 and Cauldron?

Keywords: (none) => Triaged
CC: (none) => stormi
Assignee: bugsquad => thierry.vignaud

Comment 6 Manuel Hiebel 2013-10-22 12:19:37 CEST
This message is a reminder that Mageia 2 is nearing its end of life.
Approximately one month from now Mageia will stop maintaining and issuing updates for Mageia 2. At that time this bug will be closed as WONTFIX (EOL) if it remains open with a Mageia 'version' of '2'.

Package Maintainer: If you wish for this bug to remain open because you plan to fix it in a currently maintained version, simply change the 'version' to a later Mageia version prior to Mageia 2's end of life.

Bug Reporter: Thank you for reporting this issue and we are sorry that we may not be able to fix it before Mageia 2 is end of life.  If you would still like to see this bug fixed and are able to reproduce it against a later version of Mageia, you are encouraged to click on "Version" and change it against that version of Mageia.

Although we aim to fix as many bugs as possible during every release's lifetime, sometimes those efforts are overtaken by events. Often a more recent Mageia release includes newer upstream software that fixes bugs or makes them obsolete.

-- 
The Mageia Bugsquad
Comment 7 Manuel Hiebel 2013-11-23 16:16:01 CET
Mageia 2 changed to end-of-life (EOL) status on ''22 November''. Mageia 2 is no
longer maintained, which means that it will not receive any further security or
bug fix updates. As a result we are closing this bug.

If you can reproduce this bug against a currently maintained version of Mageia
please feel free to click on "Version" change it against that version of Mageia
and reopen this bug.

Thank you for reporting this bug and we are sorry it could not be fixed.

--
The Mageia Bugsquad

Status: NEW => RESOLVED
Resolution: (none) => OLD