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I have existing MAC partition of 16GB. But my hardisk is 40GB. I want to increase the size of MAC OS . I have created another virtual disk of 30 GB which is appearing on MAC as well.

BUT what should i do to re-size the MAC partition.

I can make the image of system as it says resource busy.

how can i make image of system

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Is this a real Mac, a Hackintosh or a VM ? – Paul R Apr 21 '10 at 10:04
up vote 0 down vote accepted

What version of the MAc OS are you running?

First, you will need to boot from another disk, for example, external drive... Or Apple OS DVD...

Then use Disk Utility to create the backup image... If you are running Mac OS X 10.5 or 10.6, then you can just resize the partition via Disk Utility...

Otherwise, delete your Mac partition, after ensuring that your backup is good... And use Disk Utility to repartition the drive, and then restore your backup to the new partition...

First, so have both a 16 Gb partition, and a 40 Gb partition? What's on the 40 Gb partition? That will either need to be deleted or resized to free up space to expand the MAC partition.

  1. Grab Your Snow Leopard DVD, and boot from the DVD
  2. Once you have Booted from the DVD, choose continue, and then use the utility menu to start up Disk Utility.
  3. High light your macintosh partition's harddrive...
  4. MAKE A BACKUP. Choose File --> New --> Disk image from disk --> save the image on a different disk, and choose compressed image.... Let it run, until done.
  5. Click on the partitions, and resize as needed.
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i have mac os 10.5.6 , but i am not able to resize it using Diskutility. Can i use any bootable disk or can you provide any more infor of what type of disk can help me with making image of existing drive – Mirage Mar 5 '10 at 0:08

It's possible but depends on whether you want to spend money or not. iPartition has support for 'hot' partitioning (no data loss), but costs money.

gparted is open source but on HFS+ mac systems will not grow partitions, you can use it in combination with Disk utility to get any partitioning operation done. Note that DU is sometimes destructive of data and that you should always backup your data before any disk operation like this.

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As others have said, you cannot resize a Mac OS X HFS+ partition without the use of third party tools. What you'll need to do is copy all data off the 16GB partition to a new drive (NOT the 40 GB partition) and repartition the entire disk (The one with the 16 GB and 40 GB partitions).

If you're not able to repartition (because you don't have a spare drive) you can boot from your OS Install DVD and open "Disk Utility" from the "Utilities" menu, and you can use the "Restore" function to copy all data from the 16GB partition to the 40GB partition. You can then boot from the 40GB partition and use the 16GB partition for storing data or applications.

(You cannot copy a system drive when booted from that drive. You need to boot from another drive, such as the install DVD)

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