Partitioning problem

[dcmaccam]

Wonder if anyone can help with this!

I have a 2011 iMac which had El Capitan on its 1TB drive. I decided to split the original partition to about 500GB and create a new partition 500GB in which to install High Sierra. All went well with the machine set to boot from the second partition.

Now after using High Sierra for some time I decided to wipe both partitions on the drive and partition as 1 large partition again, then restore High Sierra from my Time Machine backup.

The problem is when I boot from recovery mode and use disk utility I can wipe both partitions but I can't seem to delete the partitions. I wanted to either delete one and resize the other or delete both and create a new one.

An I missing something. I am sure I have done this before on another machine.

 

[BrianBaughn]

You're unable to select the disk (not partition) and "Erase"?

 

[dcmaccam]

Just tried again.

Booted to the recovery partition and went into disk utilities

Selected the disk then selected erase.

Got a warning that the erase process had failed

Details were:- Unmounting disk - Could not Unmount - Operation failed

 

[BrianBaughn]

Well, now that I'm awake I suppose it's because the Recovery Partition is on there!

You could always try installing on the first partition and after you're booted into it deal with getting the partition situation fixed.

 

[Fishrrman]

Create a bootable USB flash drive installer.
Boot from the flash drive.
Open Disk Utility and try to erase the internal drive again.

 

[dcmaccam]

Hi Brian, Getting a bit nearer. Did another restore of High Sierra onto the other partition (The first partition on the disk) then deleted the second partition. Now I have the free space back. So far so good

The problem I have now is when trying to enlarge the remaining partition containing High Sierra to the full capacity of the disk. The error I get is

Running operation 1 of 2: Remove “Free space”…
The requested size change for the target disk or a related disk is too small. Please try a different disk or partition, or make a larger change.
Operation failed…

Now I am doing this from Disk Utility on the running machine, not the recovery partition

Tried the recover partition and I can't seem to get into it. Maybe I have wiped it out.
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Create a bootable USB flash drive installer.
Boot from the flash drive.
Open Disk Utility and try to erase the internal drive again.

What is the best(easiest) way to create a bootable flash drive?

 

[Bart Kela]

What is the best(easiest) way to create a bootable flash drive?

Download the macOS High Sierra Installer from the Mac App Store but do not run the installer.

Go to your favorite Internet search engine and use the parameters "macOS High Sierra bootable USB." That will result in a number of articles that describe the process. Articles from very reputable websites should be bunched at the top of the search results.

It basically requires you to erase/format an 8GB USB thumb drive. From there, you can use a free third-party app to create the bootable USB installer.

However, there's also a way of doing it through the Terminal and typing one command. This is the method I always use. That way I don't have to A.) worry if a third-party applications programmer got it right and B.) worry if some malware was surreptitiously installed on the bootable USB installer stick.

 

[dcmaccam]

Thanks, Going to do that now

 

[Marcopolo53]

this is the Terminal command I have used to make a HS 10.13.1 bootable install 16 GB USB stick. Formatted as HFS+ Journaled and gave name Untitled

sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled --applicationpath /Applications/Install\ macOS\ High\ Sierra.app --nointeraction

 

[Fishrrman]

How to create a bootable flashdrive:
(you can mess with the terminal, but other ways are easier)

1. Have a copy of the OS installer on your drive (in the applications folder or elsewhere, doesn't matter where it is).
2. Download ONE of the following free apps: "Boot Buddy", "DiskMaker X", "Install Disk Creator" (I suggest Boot Buddy)
3. Have a flashdrive 16gb or larger (it should be initialized to HFS+ with journaling enabled)
4. Launch the app (they're pretty much self explanatory).
5. The app will create the flashdrive.

Now:
Boot the Mac using the flashdrive:
- Power down, all the way off
- Insert flashdrive into USB port
- Press power-on button and IMMEDIATELY hold down the option key and keep holding it down until the startup manager appears
- Select flashdrive with pointer and hit return.
- Flashdrive will boot to the installer but DON'T RUN IT YET.
- Quit installer, go to utilities menu and choose Disk Utility.
- Make sure DU is showing you the physical drives (not the logical partitions only) -- there is a menu choice for this in the latest versions.
- Now, select the internal [physical] drive and ERASE IT to HFS+ with journaling enabled.
- When that's done, RE-open the OS installer and install it.

Notes:
I would advise you BEFORE you do the above to save a copy of the OS installer somewhere -- an external drive, etc.

 

[Marcopolo53]

Fishrrman - excellent point to save Full HS installer to external just incase the USB stick does not work on first try.

 

[dcmaccam]

Hi Guys, Thanks for all your help Got the flash drive setup, Erased the physical drive and then while still in disk utilities restored from my backup. One big partition now and all looks good. Great forum, Many thanks !!!!!

 

[Bart Kela]

In the future, you may be better off not mucking around with multiple partitions.

If you want to boot a different version of the operating system, you are better off getting a small external drive and creating a separate installation on that.

 

[dcmaccam]

Hi, yes I already did this but as the iMac was USB2 only I wanted to see how it ran speed wise on the internal HDD.

 

[Bart Kela]

All right then.

It was just a suggestion based on how much you struggled with this task.