Partition Resizing

Question

Partition Resizing

Hello,

MacBook Pro17 - Snow Leopard...

I took a look at Disk Utility.app to see if one could resize an active HD partition. It appears not so.

Could I use gparted or another app to do this?

gparted says it can shrink HFS+ partitions:
http://gparted.sourceforge.net/features.php

I've used gparted with great success on many occasions with linux.. so I thought about it for mac.

Specificially, my HD is formatted as a journaled HFS+ drive.. so not sure if that makes a difference.

Alternatively, I suppose I would either create a disk image or back up the contents of my HD to reformat the entire drive... but I'm trying to avoid that I guess.

Thanks for the comments.

Donovan

MacBook Pro, Mac OS X (10.6.1), MacBook Pro, iMac intel, iMac G3 (webserver), Powerbook G4, MacMini G5, others

Posted on Oct 25, 2009 2:10 PM

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Answer 1

LCPGUY

Level 1

10 points

Oct 25, 2009 2:39 PM in response to Donovan Brooke

You could use DriveGenius to resize an HFS partition without losing any data or functionallity. However, you cannot shrink an ACTIVE partition with any software that I know of. Disk Utility can resize a partition but you will lose everything on it. Repartitioning requires that you boot from a disk that does not contain the active partition.

John

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Answer 2

Oct 25, 2009 2:49 PM in response to LCPGUY

gparted allows repartitioning active partitions.

What I just noticed is that I think Snow Leopards Disk Utility.app may allow this as well.?? Also, the command line: diskutil may be an option as well...

quoting from the man page for diskutil:
"
resizeVolume device size [numberOfPartitions] [part1Format part1Name part1Size
part2Format part2Name part2Size part3Format part3Name part3Size ...]

Non-destructively resize a volume. You may increase or decrease its size.

A size of limits will print the range of valid values for the current
filesystem.

When decreasing the size, new partitions may optionally be created to
fill the newly-freed space. To do this, specify the numberOfPartitions,
format, name, and size parameters in the same manner as the triplet
description for the partitionDisk verb.

Resizing a volume that is currently set as the computer's startup disk
will invalidate that setting; use the Startup Disk System Preferences
panel or bless (8) to reset the resized volume as the startup disk.

Device refers to a volume; the volume's file system must be journaled
HFS+. Valid sizes are a number followed by a capital letter multiplier
or percent sign suffix as described in the sizes section at the end of
this page (e.g. 1.5T, 128M, 50%). Ownership of the affected disk is
required.

"

"
Resize a volume and create a volume after it, using all remaining space
diskutil resizeVolume /Volumes/SomeDisk 50g MS-DOS DOS 0b
"

..guess I'll try this as soon as I can make a backup.

Donovan

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Answer 3

hungryjoe

Level 2

250 points

Oct 25, 2009 9:54 PM in response to Donovan Brooke

You could also boot from the Snow Leopard install DVD and use Disk Utility there to resize the partition.

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Answer 4

LCPGUY

Level 1

10 points

Oct 26, 2009 12:29 AM in response to hungryjoe

True, there are many ways to repartition, but just not the active start-up drive which is what I thought the original poster wanted to do. In other words, you cannot repartition the currently running start-up drive.

John

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Answer 5

virusdoc

Level 1

8 points

Dec 19, 2009 4:42 AM in response to LCPGUY

not true. Snow Leopard will in fact resize the active Snow Leopard partition while you are running from it. It will also add partitions to the drive while you are running it. Launch Disk Utility, select you Snow Leopard disk, click on the + sign to add a new partition, then resize each partition by dragging it lower bar of the top partition. The click Apply. Just did it myself; works like a charm.

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Answer 6

Dec 19, 2009 7:38 AM in response to Donovan Brooke

Hi

I'm not sure why the other posters are looking beyond what's available in the interface? As virusdoc points out you can easily do this using DU. Makes no difference if it's the boot partition, another partition or even partitions on an external drive. I've done it many times and it works consistently well every time.

Another way of doing this is to use BootCamp. You can reformat the BootCamp partition afterwards in a format more to your liking. To remove the partition, reformat it again as FAT32 and use BootCamp to remove. You can do all of this 'live' with no effect in my experience on the Boot OS.

Tony

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Answer 7

Jan 2, 2010 11:09 AM in response to Antonio Rocco

As Antonio stated, DU worked well for creating partitions.. what a great new addition to DU. Just thought I'd comment on this thread to close it.

Donovan

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