MediaKit reports partition (map) too small

Discussions about using Mac OS X guests (on Apple hardware) in VirtualBox.
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JochenVDP
Posts: 3
Joined: 29. Jan 2023, 15:59

MediaKit reports partition (map) too small

Post by JochenVDP »

Hi all,

I created an OSX High Sierra guest in Virtualbox. It works great, but I made my vdi file a bit too small (40Gb). I enlarged it to 60Gb, but of course that is just the Virtualbox side of it, ic it's the Virtualbox software offering OSX a larger (virtual) harddrive. Now I still need to increase the file system size on OSX and that's where I run into trouble.

If I run Disk Utility on OSX I see a "Free space" partition and my existing High Sierra partition. If I delete the Free Space partition then my existing partition automatically takes up the whole 60Gb of the pie chart. Awesome! But when I press "Apply" I get "Operation failed". The detailed text shows me;
Volume could not be unmounted
Using live mode
...which might still be normal. It's my root volume after all. But AFAIK OSX can enlarge it's root filesystem while the OS is running (depending on what actions you use in the Disk Utility tool, there's a warning saying the OS may freeze for a couple of seconds).

But then further on in the error Details I get this;
Resizing
MediaKit reports partition (map) too small. If you recently grew your whole-disk, you should run whole-disk repair.
Operation failed...
...but then when I run First Aid on the volume I get zero errors.

I tried not enlarging my primary partition of 40Gb and simply creating a 2nd partition of 20Gb from the space I added to the vdi file ...but I get the same error.

I read about the gparted trick but that works on physical drives, as far as I understand. Not sure how I could get that to work on a virtual hrd drive within Virtualbox.

Any ideas on what to try next?
Thanks!
JochenVDP
Posts: 3
Joined: 29. Jan 2023, 15:59

Re: MediaKit reports partition (map) too small

Post by JochenVDP »

I can answer my own question in the meantime.

1) I created a clone of my vdi, just to be safe (with the VBoxManage clonemedium command)
2) In OSX, on command prompt; diskutil repairdisk disk0
3) After that Disk Utility on OSX works jusr fine

HTH someone else in the future!

Ciao,

J.
mpack
Site Moderator
Posts: 39156
Joined: 4. Sep 2008, 17:09
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Mostly XP

Re: MediaKit reports partition (map) too small

Post by mpack »

Of course this has nothing to do with VirtualBox. The procedure for enlarging the main partition of a PC hard drive is the same regardless of whether the PC is virtual or physical. It doesn't matter how the partition came to be smaller than the drive.
scottgus1
Site Moderator
Posts: 20965
Joined: 30. Dec 2009, 20:14
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Windows, Linux

Re: MediaKit reports partition (map) too small

Post by scottgus1 »

This topic is a re-post of this: viewtopic.php?f=22&t=108481&p=531363#p531363 (including spelling errors) where JochenVDP admits to using a Linux host and Mac OS VM, and was warned that Mac OS VMs on non-Mac hardware was a violation per OSX guests on non-Apple hardware, and given instructions to provide a log if the computer is an Apple. This time JochenVDP fails to mention the Linux host and provides no evidence of the Apple-ness of the host computer, if such evidence exists.

Two-week ban for violating a serious form rule. We cannot help folks break EULAs, and you will not be allowed to bring Apple's lawyers upon us, JochenVDP.

Contemplate the warning this time.
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