1 Topic by survive

  • survive
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Topic: Using the Live-CD to properly align my partitions

Hello,

I have a windows box that boots from a RAID-5 disk array that I would like to migrate over to a RAID-10 array.

I have done this several times before using the live-cd to migrate boot partitions between RAID arrays and each time it worked like a champ!

This time I have an added twist, I want to fix up the default partition alignment of the partition at the same time I'm moving it to the new disk.

Is there any way that I can do this?

This problem has been brought up before in the following post:

http://gparted-forum.surf4.info/viewtopic.php?id=1381

In which a gentleman used the live-cd to migrate a properly aligned partition to a new disk only to find that his partition pffset was reset to the default 63 sectors. I want to do basically the opposite of what happened to him....I want to take an improperly aligned partition and migrate it to a new disk with GPartd fixing the alignment issue as I do so.

Could I simply leave a tiny bit (1 Mb) of free space at the front of the RAID-10 volume then migrate the boot partition over?

Thank you for any advice you can offer.

-Will

2 Reply by gedakc (edited by gedakc 2009-02-28 18:29:09)

  • gedakc
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Re: Using the Live-CD to properly align my partitions

With the latest version of GParted (0.4.3), if you have the option "Round to cylinders" enabled then when you perform a move or copy operation the partition will be aligned to cylinder boundaries.  If you are using an MSDOS partition table, there are two exceptions to this:

1)  The primary partition at the start of the disk will start at sector 63.  This permits one track to be reserved for the Master Boot Record.

2)  Each primary partition will have track of space reserved in front of the actual partition for the Exended Boot Record.  This is also 63 sectors.

MSDOS partition tables are not only used by the MS DOS operating system, but also by Windows 9x/NT/XP.

3 Reply by survive

  • survive
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Re: Using the Live-CD to properly align my partitions

Hello,

Yes, it is exactly these 63 sectors at the start of the disk I am asking about.

Given your 2 exceptions that occur when using DOS, how would somebody ever properly align a boot partition on a windows box?

All I'm really looking to do is copy over the boot partition of the windows box in such a way that it looks like I had originally created the partition by issuing "create partition primary align=64" to diskpart.exe.

Any idea how to do that?

-Will

4 Reply by gedakc

  • gedakc
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Re: Using the Live-CD to properly align my partitions

If you wish to have more control over partition alignment, then you could investigate using a tool such as fdisk or parted.

Currently the only options in GParted for partition alignment are to round to cylinders, or to not round to cylinders.