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zerocustom1989

macrumors regular
Original poster
Sep 5, 2007
247
22
Hey guys i've got an external Hard drive with 45 gigs of free space left on it and i'd like to make 15Gb of that a separate Partition.

Is this possible to do? If so, how?
 
Hey guys i've got an external Hard drive with 45 gigs of free space left on it and i'd like to make 15Gb of that a separate Partition.

Is this possible to do? If so, how?

Well as the previous poster said it will done in Disk Utility, but I think that answer needs to be expanded on a bit assuming you want to keep the data on your drive. If you are planning to back it all up to another external disk before repartitioning the disk, then disregard the info below and just reformat and partiton the drive! ;)

First off, adding a partition to a drive with existing data without destroying the existing data (nondestructive partitioning) can only be done if:

• Your OS is 10.5 Leopard
• Your external drive was formatted for Mac use when it was empty (including both being formatted as Mas OS Extended (Journaled) and using a "GUID" partition map scheme), rather than leaving it formatted for PC use as most new external drives are when new.

To double check the existing drive format status first, go into Disk Utility to check it. Click the drive to select it in the left column and look at the info at the bottom of the screen- particularly the "Partition Map Scheme:" entry. If it is listed as MBR (or Master Boot Record) then it is still formatted as a PC drive so nondestructive partitioning would not be possible.

If it is formatted for Mac use, then the following information from Disk Utility's Help menu should guide you through adding a partition nondestructively:
Creating new volumes on a disk
You may be able to create multiple volumes on your disk without losing any data. Each volume works like a separate disk. You may need to create a new volume if you want to install multiple operating systems on your computer. Volumes can also help you organize your files.

NOTICE: Back up your data before creating new volumes on your disk as a precaution.

To create new volumes on a disk:

Select the disk from the list at the left, and click Partition.

Select an existing volume in the Volume Scheme list, and click Add (+).

Disk Utility splits the volume into two, leaving the data in one of the new volumes. If the volume is less than half-full, Disk Utility creates two volumes of equal size. Otherwise. it creates one volume large enough for the data, and another volume with the remaining space.

Resize the volumes as needed.

You can drag the dividers between the volumes in the Volume Scheme list, or you can select a volume in the Volume Scheme list, and then enter a value in the Size field.

Choose how to format the volumes that will be erased or created.

For each new volume, select it, enter a name, and then choose a format.

Click Apply.
 
Well as the previous poster said it will done in Disk Utility, but I think that answer needs to be expanded on a bit assuming you want to keep the data on your drive. If you are planning to back it all up to another external disk before repartitioning the disk, then disregard the info below and just reformat and partiton the drive! ;)

Ah yea, I suppose I should provide some more information.

I do want to attempt to keep the data and i don't have any other place to back it up to, lol.

175Gb is a Time Machine Partition.
The other bit is FAT32 format.

It's this other bit that i want to divide into 2 pieces. The +- buttons in disk Utility are grayed out when I highlight the FAT32 portion though :-\

Is it because it's a FAT32 format? I suppose a WindowsBeta test run can wait...
 
If you have norton partition magic for mac, your life will be easier.

I just dont know if there is "partition magic for mac" :)
this tool is very good in creating partition to an active/loaded drive... it moves files seamlessly..
 
Ah yea, I suppose I should provide some more information.

I do want to attempt to keep the data and i don't have any other place to back it up to, lol.

175Gb is a Time Machine Partition.
The other bit is FAT32 format.

It's this other bit that i want to divide into 2 pieces. The +- buttons in disk Utility are grayed out when I highlight the FAT32 portion though :-\

Is it because it's a FAT32 format? I suppose a WindowsBeta test run can wait...

Ok, got you. You are right that Disk Utility will not do anything with a FAT32 partition unfortunately as far as resizing/splitting goes.

One workaround for that would be to download the free Mac utility WinClone which is for backing up your Windows installation as a disk image. You could back up your Win installation, then blow away the FAT32 partition in Disk Utility then re-establish two partitions in the space freed up by doing that. Disk Utility can then be used to format those two partitions as FAT32, after which you could restore (using WinClone again) the disk image you made to one of the partitions, leaving the other ready to experiment on.

Or you could shrink the Mac OS partition with Disk Utility then establish a new partition in the newly freed up space, then format that partition only as FAT32. From past experience that carries the problem of rendering the existing FAT32 partition non-bootable without some fairly heavy duty Windows repair routines though.

On the other hand, probably a lot simpler to just wait 'til you have another drive to use to back up this one (since that would be highly recommended anyway) and set up the existing one from scratch using the instructions in several threads regarding triple boot disks! ;)

BTW- Will the Windows 7 beta install on a FAT32 partition?
 
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