aBarel
Level 1 (1 points)

Q: "Macintosh HD" partition is not mounted properly

This question is about "Macintosh HD" partition that is not mounted properly.

If you are an experienced Mac user with good understanding in the OSX boot process and especially the mount procedure of the internal HDD, please read this and I'll appreciate your assistance.

Thank You for your patience reading this long issue.

 

Platform: iMac 2013, 1T fusion drive, original partitions (nothing was changed), running Yosemite (newest).

I think it would be worth mentioning (or on the other hand may not be relevant) that Paralles is running on this iMac [U]under[/U] OS X (not as a separate boot).

 

The Problem: The hard disk icon on the desktops top right corner (enabled by Finder->Preferences->Sidebar->Hard Disks turned on) usually titled "Macintosh HD" changed its title to a very long gibberish string. Other than that, I couldn't identify any operational issues with the iMac. For now ;-)

 

Gibberish.png

It annoyed me so I did some digging and compared the with a Mini Mac that has the same 1 Tera bit fusion drive (no Paralles is on that system).

That's what I found:

 

1. Directory "/Volumes" is empty, ls -la /Volumes shows nothing!

On the healthy (Mini Mac) system you can see that a link exists :

lrwxr-xr-x   1 root  admin     1 May 23 10:41 Macintosh HD -> /

 

2. Applying diskutil list  on the iMac:

 

iMac diskutil.png

 

While on the Mini Mac (healthy system):

 

Mac Mini diskutil.png

 

You can see that on the Mac Mini (healthy) system "/dev/disk2" is mounted while on the iMac this mount doesn't exist! That may be related to the fact that "/Volumes" doesn't contain the relevant link (as described in (1.) )

 

3. Applying diskutil info /  on the iMac:

iMac diskutil info.png

 

Looks very wrong... believe it or not this system works...

 

 

4. I didn't succeed to rename the disk icon gibberish title (the icon that is located usually on the top right desktop corner) back to "Macintosh HD". It stayed very long gibberish string. even "disk utility" didn't help. Each time I tried to change it the system produced an irrelevant error message telling me "The name xxx can't be used. Try using a name withe fewer characters, or with no punctuation marks"

 

5. "Disk Utility" behaves differently on the two systems: On the Mini Mac (healthy) system it shows a "Logical Volume Group" icon named "Macintosh HD" and under it, aligned to the right it shows another "Macintosh HD" icon for the "/" mount point.

 

On the other hand "Disk Utility" on the broken iMac shows alright the main "Logical Volume Group" icon, but underneath it, there is an icon with the gibberish title and the description below for that icon says:

Mount Point: Not mounted

Format: Logical Partition

Owners Enabled: -

Number of Folders: -

Capacity: 1.12 TB

Available: -

Used: -

Number of Files: -

Disk Utility on iMac.png

You can see that when the gibberished partition is selected (in the above picture), the "Verify /Repair" buttons are greyed out !

 

My Question: I'm not so deeply familiar with OSX (more of a Linux/Unix guy) but it definitely seems like something is broken with the mount process during boot. The question is why it is broken, and how to fix it.

I'm not sure that the missing link under "/Volumes" is the original cause of the problem. How these dedicated links under "/Volumes" directory are supposed to get there? I was not sure if adding manually the "Macintosh HD" link to root is the right solution, maybe some boot script that uses other config files adds this link automatically... More than that I'm not absolutely sure about that link permissions and ownership and how to create it...

A bigger question that I have is how the system is working at all if the mount of the main logical partition failed ??? Very strange...

 

For the cause of the problem, my suspicious is falling on the Paralles app since it the only program that may mass with partitions, but this is just a gut feeling and there is a good chance that I'm wrong. Maybe something went wrong during the migration to Yosemite.

 

Thanks for you patience

Hope you can help

iMac (21.5-inch, Late 2013), OS X Yosemite (10.10.3), null

Posted on May 30, 2015 6:16 AM

by Topher Kessler,Solvedanswer
Topher Kessler Topher Kessler
Level 6 (9,866 points)
A:

While you could spend hours monkeying around with partition tables, corestorage setups, and volume formatting routines, your best bet here is going to be to set up your drive from scratch. The Fusion Drive is a combination of two separate hard drives (an SSD and a HDD--your SSD is disk0 and your HDD is disk1, with the corestorage volume being disk2 in the "diskutil list" output above), and thereby employ both classic partitioning and corestorage volume management to provide your Mac with a single storage medium upon which to store OS X and your data.

 

It appears you have some corruption in your Mac's corestorage setup. If you want, you can run the following command to see the structure of corestorage on the systems:

 

     diskutil cs list

 

However, I suspect this is not going to give any details that will help address this problem. Ultimately, if you back up your system and format it, then you will ensure the drive's setup is healthy. To do this, after backing up your Mac, boot to Recovery mode by holding the Command-R keys at startup, and then use Disk Utility to erase the partition on there. For fusion drives on supported Macs (those that ship with Fusion drives), Disk Utility should clear the corestorage partition and rebuild the Fusion drive setup. You can then use either OS X's backup recovery tools, or your cloning software, to restore OS X to the system.

 

Above everything, though, be sure you get your files backed up.

Posted on Jun 2, 2015 6:33 AM

Close
aBarel

Q: "Macintosh HD" partition is not mounted properly

  • All replies
  • Helpful answers

Previous Page 2

  • by Linc Davis,

    Linc Davis Linc Davis Jun 2, 2015 2:46 PM in response to aBarel
    Level 10 (208,037 points)
    Applications
    Jun 2, 2015 2:46 PM in response to aBarel

    So if you don't mind please repeat the relevant procedure you suggest for backup, system reinstall and data restore?

    I've already suggested a procedure. I see no point in repeating it. If you don't like any of the suggestions, click the Support link at the top of this page to schedule a call from Apple Support.

  • by Topher Kessler,

    Topher Kessler Topher Kessler Jun 2, 2015 8:45 PM in response to aBarel
    Level 6 (9,866 points)
    Jun 2, 2015 8:45 PM in response to aBarel

    Time Machine does approach file handling with a bit of complexity, so it may fail if there are odd problems with the drive. On the other hand, there are a number of more basic approaches, such as using a cloning tool to create a per-file mirror of your drive. I'd recommend you give this a shot, with a tool like Carbon Copy Cloner (there are many out there to choose from). With this, you set the source as your hard drive, and the destination as your external drive, and then let it do its work. Hopefully it will proceed without errors, but at the very least, try manually dragging and dropping files from your system to a backup drive in order to save them.

     

    Do what you can to preserve your data, and when you are comfortable that it is backed up appropriately, then you can look into formatting it. This should be doable by booting into Internet Recovery (hold Option-Command-R at startup), but can also be done by accessing your Mac in Target Disk Mode from another Mac, or by booting to an external boot drive (e.g., attach a spare hard drive and use Recovery Mode to install OS X to it, then boot off of it to access your internal drive). In all approaches, you can try using Disk Utility to format your drive, but should be able to use the Terminal to format the drives and then have Disk Utility set them up again as a fresh Fusion drive.

Previous Page 2