Partitioning a disk using disk utility

I bought a rather large capacity external hard drive for use as a Time Machine backup drive along with MacOS 10.5, and figured I'd partition off 100GB of it for use as a bootable partition. So, I looked up how to partition a drive in Disk Utility, and it said:
"*To partition a startup disk:*
1) If you’re partitioning an external hard disk, make sure it’s connected to your computer. If you’re partitioning the disk you are now using as a startup disk, you must start up using another disk such as your Mac OS X install disc.
2) Open Disk Utility. If you’re in the Mac OS X Installer, choose Utilities > Disk Utility. Otherwise, double-click Disk Utility, located in the Utilities folder in your Applications folder.
3) Select the disk in the list that you want to partition, and click Partition.
4) Choose the number of partitions from the Volume Scheme pop-up menu.
5) If you can’t choose the number of partitions, you may be trying to partition your startup disk. Start up your computer with another disk, such as your Mac OS X install disc."
The external hard drive showed up in the side bar, but there was nothing in the disk utility window called "Partition" for me to click on. Nothing called "partition" existed in the menus either. I tried to customize the toolbar, thinking that "Partition" might be a button not currently on the tool bar, but I found nothing.
(I would attach screenshots of both the help window and Disk Utility, but I can't do that here.)
How do I partition a disk using Disk Utility?
Message was edited by: Berkana

3) *Select the disk* in the list that you want to partition, and click Partition.
When you select a disk that DU can partition, that is, not the volume currently booted from,
you can see the five buttons
First Aid | Erase | Partition | RAID | Restore
Also:
Don't forget to choose the "Mac OS Extended (Journaled)" formatting option.

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I can't delete partition in disk utility, it keeps telling me that "the changes are too small"

I previously split my disk into two different disks, however I want to combine them together again, yet i was unable to delete the second partition. I can't delete partition in disk utility, it keeps telling me that "the changes are too small"
Plz help!!!!!!

Make at least two complete backups of all your data. Boot from another drive and partition this one as desired. Restore the data.

Partition with Disk Utility?

I just got a 500gb external drive that I want to partition. Disk Utility is supposed to be able to do this. The help file says "Click Partition" in the Disk Utility window. I see nothing in the window with "Partition" on it. A screen shot I've seen (from LaCie's hard drive manual) shows five buttons across the top of the window: First Aid, Erase, Partition, Raid, Restore, but my Disk Utility only has 4 buttons. The "Partition" button is not there.
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I've clicked on the external drive icon along the left column but nothing pertaining to partitioning shows up.

That is because you have your boot volume selected in the left hand column, select the Hard drive itself, the one with the Manufactory ID number. It should be at the very top.
Joe

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thank you,
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Hello RalphR_MI,
Take a look at this page, which lists several articles. Please let me know if any of these help you restore your backup.
Also, take a look at this article, as well as this one.
I hope this helps. I'm not sure of a few things, so I'm sorry for sending you so much, but I'm confident it will give you something new to try.
Please let me know if this helps. Good luck!
↙-----------How do I give Kudos?| How do I mark a post as Solved? ----------------↓

I deleted my Boot Camp partition with Disk Utility and now I cannot reclaim the freespace?

I deleted my Boot Camp partition with Disk Utility and now I cannot reclaim the freespace?
And when I try to add a partition to the free space, and try to apply I do this:
I press apply and it does its thing for like a second, I switch tabs and I get this:
No matter how many times I reboot it doesn't work. Please help

diskutil list:
diskutil mergePartitions:

Difference between using bootcamp and building partitions with disk utility

hy everybody,
i successfully bought a mac (that was easy , installed windows 7 with bootcamp (quite easy) and now i 'd like to add linux also (considering ubuntu).
before i try to do it with bootcamp i'd like to know what the impact could be...
so i wonder; what does boot camp do and why shouldn't i do it manually with disk utility?
all inputs are welcome
cheers

Why not start by filling out hardware in your profile .sig as it makes a difference.

Can't boot into Windows after splitting Mac partition with Disk Utility

Hi everyone,
I installed Windows 8 with BOOTCAMP, creating a large 871 GB partition with a smaller 127 GB partition for Windows. After installing Windows, I then went back to Disk Utility to shrink the Mac partition and add two new partitions, one for storage and another blank, hoping to use it to install Linux into one day.
I did that, and now Windows doesn't boot. A Windows blue screen tells me I need to use the Windows DVD to repair it.
I tried to use Disk Utility to delete the two new partitions I made and grow the Mac partition back to the max size of 871 GB. But it doesn't let me do this. The Disk Utility log doesn't report an error and thinks it worked but the partition stays the same size. However if I make the partition a little smaller, like 870 GB then it works. I'm wondering if the Recovery partition is hiding there and preventing me from fully expanding the Mac partition.
What can I do?
Here's what I get if I type in sudo gpt -r -vv show disk0:
Code:
gpt show: disk0: mediasize=1000204886016; sectorsize=512; blocks=1953525168 gpt show: disk0: Suspicious MBR at sector 0 gpt show: disk0: Pri GPT at sector 1 gpt show: disk0: Sec GPT at sector 1953525167 start        size index contents 0           1         MBR 1           1         Pri GPT header 2          32         Pri GPT table 34           6 40      409600      1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B 409640 1701278816      2 GPT part - 48465300-0000-11AA-AA11-00306543ECAC 1701688456     1269536      3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC 1702957992     1846360 1704804352   248002560      4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7 1952806912      718223 1953525135          32         Sec GPT table 1953525167           1         Sec GPT header
Here's what I get if I type sudo fdisk /dev/rdisk0:
Code:
Disk: /dev/rdisk0     geometry: 121601/255/63 [1953525168 sectors] Signature: 0xAA55 Starting       Ending #: id cyl hd sec - cyl hd sec [     start -       size] ------------------------------------------------------------------------ 1: EE 1023 254 63 - 1023 254 63 [         1 -     409639] <Unknown ID> 2: AF 1023 254 63 - 1023 254 63 [    409640 - 1701278816] HFS+ 3: AB 1023 254 63 - 1023 254 63 [1701688456 -    1269536] Darwin Boot *4: 07 1023 254 63 - 1023 254 63 [1704804352 - 248002560] HPFS/QNX/AUX
Here's what I get with gdisk:
Code:
Disk /dev/rdisk0: 1953525168 sectors, 931.5 GiB Logical sector size: 512 bytes Disk identifier (GUID): 6075110F-7CEF-4604-85EE-6231B850E2AE Partition table holds up to 128 entries First usable sector is 34, last usable sector is 1953525134 Partitions will be aligned on 8-sector boundaries Total free space is 2564589 sectors (1.2 GiB) Number Start (sector)    End (sector) Size       Code Name 1              40          409639   200.0 MiB   EF00 EFI System Partition 2          409640      1701688455   811.2 GiB   AF00 1 TB APPLE HDD HTS54101 3      1701688456      1702957991   619.9 MiB   AB00 Recovery HD 4      1704804352      1952806911   118.3 GiB   0700 BOOTCAMP

Okay, the code I typed didn't display properly in the forum. Let me try again.
Here's what I get when I type
sudo gpt -r -vv show disk0:
gpt show: disk0: mediasize=1000204886016; sectorsize=512; blocks=1953525168
gpt show: disk0: Suspicious MBR at sector 0
gpt show: disk0: Pri GPT at sector 1
gpt show: disk0: Sec GPT at sector 1953525167
       start        size index contents
           0           1         MBR
           1           1         Pri GPT header
           2          32         Pri GPT table
          34           6
          40      409600      1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B
      409640 1701278816      2 GPT part - 48465300-0000-11AA-AA11-00306543ECAC
1701688456     1269536      3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC
1702957992     1846360
1704804352   248002560      4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7
1952806912      718223
1953525135          32         Sec GPT table
1953525167           1         Sec GPT header
And when I type fdisk /dev/rdisk0 I get:
Disk: /dev/rdisk0          geometry: 121601/255/63 [1953525168 sectors]
Signature: 0xAA55
         Starting       Ending
#: id cyl hd sec - cyl hd sec [     start -       size]
1: EE 1023 254 63 - 1023 254 63 [         1 -     409639] <Unknown ID>
2: AF 1023 254 63 - 1023 254 63 [    409640 - 1701278816] HFS+
3: AB 1023 254 63 - 1023 254 63 [1701688456 -    1269536] Darwin Boot
*4: 07 1023 254 63 - 1023 254 63 [1704804352 - 248002560] HPFS/QNX/AUX
Kappy,
I can boot into OS X just fine so if possible, I'd like to avoid reformatting everything. If you know of a way I can add more than 2 partitions with OS X and Boot Camp, please let me know. As far as I know, rEFInd can recognize more than two partitions, but I don't think it can edit partitions on a GPT / hybrid MBR system. Or am I wrong?

Can't create a 3rd partition in Disk Utility

Long story short I have used Boot Camp to get Windows, so I have 2 partitions. But, I need to create another partition to install another copy of Windows on it, but Disk Utility has grayed out the '+' to allow me to create a new partition. All I can do is delete the 'BOOTCAMP' partition which I don't want to do. I tried another way by going into Boot Camp Assistant and installing Windows through there. I have a bootable USB drive and I know how to install it, all that's stopping me is the partition issue.
Any ideas?
If it helps, I'm using a Late 2013 MacBook Pro with a 15" Retina Display, 2.5 GHz, 512 GB SSD, 16 GB RAM and a NVIDIA GT 750 M.
Thank you for your help

Good thing to mention that, I forgot to do that.
Unfortunately it did not help.. The screen to remove the existing Boot Camp partition does not pop up, it just tries to create the new Boot Camp partition.
The partition I'm trying to create it 150GB. The 50GB mentioned above was on the stock Fujitsu 250GB disk.
Edit:
I'm actually trying to avoid using Boot Camp Assistant.. I became to dislike the utility due to problems creating a partition on my previous HD.
I would like to create a partition using Disk Utility and then install Windows 7 by selecting that DVD to boot from.
Thank you for the tip though, I'll post it there as well!

Partition errors - "Disk Utility can't repair this disk"

I partitioned my external 1TB WD HD into two drives (950GB + 50GB) using Disk Utility (OS X Mavericks 10.9.1). However the 950GB partition will no longer mount. It is recognised in Disk Utility, but grayed out. "Verify Disk" and "Repair Disk" in Disk Utility lead to the worrying error message "Disk Utility can't repair this disk."
From the Disk Utility logs, the initial partition was successful:
Partition 1:
Name: “Media Centre”
Size: 948.13 GB
File system: Mac OS Extended (Journaled)
Do not erase contents
Partition 2:
Name: “Media Centre 2”
Size: 50.03 GB
File system: Mac OS Extended (Journaled)
Do not erase contents
Mounting disk
Partition complete
Afterwards, I changed the name of the second partition “Media Centre 2” to "BOOTCAMP" (I was going to try to install Windows 7), but then changed my mind and tried to remove the second partition. At that point the log gives the error "Mount of “Media Centre” failed".
Partition 1 ("Media Centre") now seems to be in limbo, stuck as 950GB, and "Verify Disk" and "Repair Disk" in Disk Utility lead to the worrying error message "Disk Utility can't repair this disk". Also in Disk Utility, Partition 1 ("Media Centre") now has the format classification "Mac OS Extended" rather than "Mac OS Extended (Journaled)".
Any idea how I can get my hard drive to mount and get the data back?

In Disk Utility select the Top most entry on the left, the drive model and or manufacturer name and size entry, then click the Partition tab and Repartition it to your liking. If that fails the drive is bad.

Can´t delete a partition. Disk utility greyed out.

I have a problem. I can't delete or build a partition on my Macintosh HD. The options for deleting or build a partition are greyed out. I try to boot from a external drive and open disk utility, but still the same problem. I also tried iPartion but it don't work.
I have a iMac (late 2013) with 3 TB fusion drive on OSX 10.9.4

Macs with Fusion drive use CoreStorage to manage disk objects.
You should use Terminale and command
diskutil coreStorage

Trouble creating a third partition in Disk Utility.

Hello, I am fairly new to the Mac as I recently switched from a PC just a few weeks ago. Now you won't be dealing with a "noob" here because I am a power user when it comes to the PC so not too much adjustment has been needed for OS X.
So I Have the MacBook White 13" Early 2009 model (MacBook 5,2). I upgraded it to a 320GB HDD and installed snow leopard the first day I got it. Then I decided that I wanted to create a bootcamp partition and install Windows 7 (Not hard to do when you have Google to provide you with any knowledge you require). Googling is how I and most people learn these days so I have gained quite a lot of experience with OS X for the 3 weeks I've been using it.
Anyway, BootCamp went as smooth as it could get, Windows 7 runs when I boot, Both OS X and Windows 7 Partitions work perfectly.
Now, My desire is to create a third partition of 25GB with Disk utility by shrinking the main OS X partition (BootCamp is at 60.73GB, OS X is at 259GB).
The reason for this partition is to Install OS X Lion Dev preview.
For some reason it is proving impossible to create this partition. The first time I tried, I had a kernel panic, but I was wondering if this may have been because I was simultaneously burning a disc image to a DVD and Creating a third partition on My HDD.
After I restarted, I again attempted to partition. Setting a new Mac OS Extended (Journaled) partition of 25GB on the Main OS X partition. It then began partitioning, trouble is it seemed to completely freeze the UI and I could not do anything other than move my cursor, I thought this was maybe because the hard disk was being partitioned and therefore affecting anything on the disc during the process (Hence the UI Freeze). So I decided to leave this for about half an hour, but I had noticed that it was still in the exact same state, it seems to be getting stuck on the Shrinking phase, which is of course the actual partitioning and shrinking of the Main Partition. I also thought I should check if there was any Hard disk activity going on, as the UI was locked up, I could only listen to the drive, the drive was spinning but the actuator head did not sound like it was reading or writing anything, it was just parked. No activity.
As it seemed to be stuck on "shrinking" forever and the UI was still locked, I forced a shutdown. Both partitions were unchanged as bootcamp and the Main partition seemed to work perfectly. So I tried the process again, this time I tried, and the UI did not lock up but I did receive the error "could not modify partition map because filesystem verification failed". So I did some googling again and arrived at the conclusion that I need to repair the disk. So I checked this in disk utility by verifying the disk, and Lo and Behold, It reported that the disk needed repairing. Now at the moment I didn't have my OS X install disk, so after another visit to google I found that using fsck -yf works exactly the same in single user mode and repairs the Disk. After the repair, I booted into OS X again and tried to partition again... And the same happened, UI Freeze, No error report, Just a pure freeze at "shrinking". I Cannot find a way around this and it's beginning to frustrate me. I attempted a few more times, force shuting down, Repairing, then trying to partition, But I'm getting Nowhere.
I'd be very thankful if you can help me solve this problem.
Thank You
Jordan L. Sutton.

Thank you for that link, with a little reading I did find that I may not have enough free contigous space on my Hard drive. I found that this could be fixed with a defrag. Now I know Macs should not need defragmenting due to their great extended format which manages this automatically. But using iDefrag, a software available for defragmenting a Mac hard drive. This seemed to free up contigous space and after a defrag, I was able to try again with creating a third 25GB partition, and it worked like a charm. I'm not sure what the core issue was but even though Macs should never need defraging, it did work.
Thank you.

How can you change the primary partition in Disk Utility?

I have made another partition using Disk Utility to install Snow Leopard. On my main partition Lion is installed but when i boot into Snow Leopard and try to delete the Lion partition it comes with an error "This operation requires a newer version of Mac OS X for this disk". I tried deleting the partition from Recovery HD but it says it couldn't unmount the disk.
Is this because Lion is the main partition, can you even delete the main partition?
And if I do delete the main partition will i be able to move the Snow Leopard partition "upwards" in Disk Utility?

ralphfromhome wrote:
1) First of all what is GUID.
It's the "partition map scheme" Apple uses so your firmware knows what is what on your boot drive, what partitions there are and what format they contain.
2) Secondly, would I just be able to make a new image in disk utility and use that instead of an external hard drive?
No, you need something to boot off of and remove all data off the internal drive that's going to be reformatted with a new parttion, that's why you use the free Carbon Copy Cloner, it does both in one shot and it "blesses" the drive to make it bootable.
3) When I use Carbon Copy cloner will it only copy Snow Leopard Installation or all of my files also?
It copies everything in your Snow Leopard partition to the external drive, files, programs the OS everything except whats in the Trash.
4) In your 8th step you mentioned repairing permissions on both. Both of what?
Both drives, the internal and the external clone in Disk Utility (ignore the long list that appears)
It's a safety check to make sure your permissions are set back to original settings, I think the newer version of CCC now does this, but I havent' checked, doesn't hurt to do it again.
5) If you still feel like typing can you tell me how long this whole process might take?
Formatting a external drive
You should Erase with Zero option first, that will take a hour per 500GB
Formatting shoud be rather fast, a few minutes.
Cloning Snow Leopard to the external drive should take about a hour per 500GB
Formatting the internal drive a zero erase first for safety should take another hour per 500GB
Reverse cloning Snow Leopard back onto the internal drive should take another hour per 500GB
Good thing about it, it's pretty much all ciick and go watch TV while it works.
I was actually planning to make a Genius Bar appointment to fix it, by the way does that cost much?
No idea, but you don't have to pay if you get a external drive for $70 or so, CCC is free.
You get to keep the external drive and use it later for cloning as hard drives die all the time, the clone would get you back to using the computer.

Can't partition with disk utility. Options greyed out

Hi,
Bought a used 4 TB Seagate drive, formatted it , checked the speed 150 MB/s read/write and made a partition. Apparently it worked perfect.
However after this first partition the drive is behaving erratically. I can not modify partitions anymore nor delete them. Repair disk is not finding any problem either from the system or from the recovery partition.
I am starting to believe the disk is damaged. Beside the partition problem the disk is behaving fine. Anyone please?

Thanks. I already did. The disk whose partitions I can not modify is blank. It is the 3rd disk in the Mac pro. I formatted and created 2 partitions. But then I can not create more partitions nor delete them. I tried from the Recovery volume with the same result. Partition options remain greyed out.
Beside that, if you look at the pictures, CCC 4TB and CCC 4TB2 are the same physical drive but seem to be different in disk utility. Is this disk damaged?

How do I make NTFS format for partition in disk utility ?

Hi, how would I format a external hard drive partition to NTFS for windows ? There's no option in disk utility. Only MS-DOS ( FAT ) , ExFat, free space, Mac OS extended- journaled, Mac OS extended, journaled case sensitive.
The other partition would be mac os extended journaled . Does it have something to do with partition scheme ? I'm running mountain lion .

anonymous4a wrote:
ok i wasn't clear,
That would have helped.
I want to make a backup of my windows partition and mac partition on my macbook pro retina on to ONE external hard drive.
Ok, so you have OS X and Windows in BootCamp on your Retina MBP.
You want to make a backup of both to one drive and this is what you should do.
Get another powered external drive slightly larger than your internal boot drive.
Use Disk Utility to format this external drive with a GUID partition table and two partitions each slightly larger than your MacintoshHD and BootCamp partitions
The first external partition formatted OS X extended journaled (MacintoshHD2) and the second one exFAT (WindowsBootcamp2) The OS X parittion is first at the top.
Download these two programs, Carbon Copy Cloner and Winclone 3.
Use CCC to clone the OS X MacintoshHD to the MacintoshHD2, and use Winclone 3 (runs in OS X) to backup Windows BootCamp to WindowsBootCamp2.
The OS X clone on the external drive is bootable if you hold the option key down while booting the computer.
The Winclone 3 partition on the external drive is not bootable, it's a backup only as Windows is copy protected and will invalidate itself if it ran.
Warnings:
Don't use CCC to clone BootCamp, it's not designed for that and won't restore to run Windows.
There is no software that can do both parittions at the same time and be bootable or restore properly to a different sized drive or restore the RecoveryHD partition. Some have tried with some other softwares and have problems with lost drive space.
Both partitions have to be cloned/backed up seperatly as there is some intelligence involved and the user needs the option to adjust partition space.
Also, backup your files in Windows (and OS X) to a regular external exFAT drive that was formatted on the oldest Windows machine your going to connect to, OS X doesn't do exFAT correctly so Windows can't read it. The exFAT partition using Winclone likely won't be readable by a Windows PC.
Most commonly used backup methods
.Drives, partitions, formatting w/Mac's + PC's
Again, you can't run Windows from a external drive, it's copy protected and takes the hardware id's into that, so it's essentially worthless to use NTFS on the external WindowsBootcamp2 partition.
All you need is a partition format that can handle over 4GB sized files, and exFAT is ideal and free to use. FAT32 can't handle 4GB+ files and is being phased out.
http://arstechnica.com/information-technology/2013/06/review-is-microsofts-new-d ata-sharing-system-a-cross-platform-savior/

Partitioning w/Disk Utility

I just bought SuperDuper and I'm going to clone my internal harddrive onto a firewire external that already has files on it.
I'm planning to copy everything that's currently on external hd1 onto external hd 2 so I can partition external hd1 to prepare it for the SuperDuper clone.
I've never done a partition before using Disk Utility and was wondering if there's anything I need to pay particular attention to or be aware of.
Thanks for any tips/'heads-up' you can share.

Hi ramonekalsaw
You pretty well have it covered! Disk Utility does a great job of walking you thru the process, just take your time and read the small print along the way.
For your Intel iMac set the:
Partition Map Scheme to "GUID Partition Table"
and
Format to "Mac OS Extended (Journaled)"
Also skim thru Disk Utility Help and Ken Stone's article below:
http://www.kenstone.net/fcphomepage/partitioningtiger.html
Dennis

Can't resize partition in Disk Utility (OS X 10.6.7)

For some reason resizing a partition fails with the error, "Partition Failed. Failed with error: Could not Modify partition map because filesystem verification failed." Any ideas? I was squeezing down an existing partition to make room for another and I'm stuck. I read where in OS X, "... this just works."
Screen Pic

Thanks, Jolly. I should've said that I'm already using an external USB startup system, with a known good OS X 10.6.7 OS version installed/updated to boot up with, not the drive being worked on. I don't think that I would've gotten to this point otherwise.
I found the answer, though, thanks to your implication/confirmation that it should work. Turns out, had to repair the partition, not the root drive. The root drive had given no errors, but the partition did give a couple when checked (who knows? Maybe Disk Util put them there...).
So after I fixed those and checked for no errors, then I was able to compress the existing filesystem and make a new partition for a new OS. Then I was able to boot back to the startup volume to do the install. I am going to try to use Server on this Mini. Is there anything I should look out for?

Partitioning a disk using disk utility

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