Hard Disk Permissions

[Socrates 2.0]

I accidentally changed permissions on a secondary internal hard disk (not the applications/startup drive) storage drive only.

I tried "right click on drive/get info/change ownership & permissions" but it would not keep changes. Every time I checked boxes to "Read & Write" it would automatically change back to "No Access" as soon as I exited the Get Info box. At this stage the drive in question still appeared on the desktop, until I rebooted the computer now it does not appear on the desktop at all.

The drive appears in Disk Utilities however the volume icon in utilities has changed from a hard drive to what appears to be a piece of paper and "Disk Permissions" is dimmed in this window. The drive also appears in System Profile as normal.

The alias for the drive appears via "Finder/Go to Folder/Volumes" however trying access the drive this way pops up a window that says the original item cannot be found. I can "right click on volume alias /get info" but still get no access and I notice that the "Fetching" indicator under "More Info" revolves eternally.

Does anyone know how I make the drive visible again, and how to restore full read/write permissions.
The machine is a Mac G4 MDD running OSX Tiger 10.4.11.

I would be very grateful for any advice you may have.

 

[oldscribe]

Hi,

Are you able to run disk repair in this drive?

 

[Socrates 2.0]

Hi,

Are you able to run disk repair in this drive?

Thank you for your reply.

Yes, ran disk repair previously which came back with the following

1 HFS volume checked
No repairs were necessary

Drive still not visible.

Cheers,

 

[oldscribe]

Hi,

Am thinking you may have to re-format drive, is it possible to back it up?

 

[Socrates 2.0]

Hi,

Am thinking you may have to re-format drive, is it possible to back it up?

Hi,

Formatting is not an option in this circumstance, backup is not possible because I cannot access drive to backup data to another location.
I am hoping the solution will somehow be within resetting the ownership and permissions on this drive because of the high value data that exists on it.

Cheers,

 

[oldscribe]

Hi,

If you can not change permissions from your adim account, this does seem odd, I would connect drive through external caddy.

 

[Socrates 2.0]

Hi,

If you can not change permissions from your adim account, this does seem odd, I would connect drive through external caddy.

Hi,

We must be on the same wavelength, I tried connecting the drive through an external firewire caddy since my last posting, unfortunately same problems exists, drive not visible.

I cannot be the only person to have messed up drive ownership permissions, it was so easy to do. Hoping somebody out there has tripped over the same issue and can offer advice.

Cheers,

 

[oldscribe]

Hi,

Just try this, plug the drive in then reboot the Mac, what is the result?

 

[Socrates 2.0]

Hi,

Just try this, plug the drive in then reboot the Mac, what is the result?

Hi,

Plugged in the drive and rebooted (restarted) the mac as you suggested, nothing.
Also tried a cold boot (full shutdown and restart) nothing. The caddy is a USB/Firewire caddy so I also tried this procedure both ways and still nothing.

Everything remains as in my first post, drive not visible on desktop. It is visible but not accessible via Disk Utilities, System Profile and Volumes.

Cheers,

 

[oldscribe]

Hi,

Can you plug this drive into another Mac? If so does it mount on the desktop, if yes try and change its permissions by right clicking > get info.

 

[Socrates 2.0]

Hi,
Can you plug this drive into another Mac? If so does it mount on the desktop, if yes try and change its permissions by right clicking > get info.

Hi,

Have tried plugging drive into into other computers including a PC previously, no result. Also tried launching Mac from the OSX instal disk, nothing as well.

Every combination of plugging the drive in that I can think of has given the same result. I also tried Carbon Copy Cloner to clone the rogue drive to another drive and then reformat, access was denied in CCC.

I need to discover some back door into ownership & permissions to solve this I think.

 

[tompatrick]

hey there, I found some important link that might help you http://osxdaily.com/2011/09/23/view-mount-hidden-partitions-in-mac-os-x/

 

[Socrates 2.0]

hey there, I found some important link that might help you http://osxdaily.com/2011/09/23/view-mount-hidden-partitions-in-mac-os-x/

Thanks for link, however this particular one you sent is for the next version of OSX onwards, I am still running 10.4.11 on this machine. I had actually found this debug menu previously for my version and activated it which is why I said in my first post that I could see the drive in utilities but could not access it. The two debug menus look almost the same except that the one you sent has one extra option "show every partition".

 

[Socrates 2.0]

Okay, for everyone following this here is the solution for restoring ownership and permissions in OS X 10.4.11
So you know which is which the rogue drive that lost permissions is called "Audio Drive 2" and the startup drive is called "Applications Drive" and be warned if you have never played around in Terminal before you should only do it with adult supervision!!

Permissions were a little bit too restrictive, but more importantly the user immutable flag was set set (indicated by the 'uchg' ). Copy/paste the following commands into Terminal:

sudo chflags nouchg /Volumes/"Audio Drive 2"
sudo chmod 755 /Volumes/"Audio Drive 2"
ls -alO /Volumes
echo "done"

You will be asked for your admin password. Enter it at the prompt. As you enter your admin password, nothing will be echoed back to the screen. This is a normal security precaution. If you've never used the sudo command before, you will get a warning about the potential dangers of using sudo. Read the warning--it's very true, and it's dangerous to enter commands that start with 'sudo' if you don't understand what they do.

The first command above removes the 'uchg' flag, which is the user immutable flag, from the "Audio Drive 2" volume.

The second command above makes the permissions on that drive less restrictive. After issuing that command, the permissions should look like
drwxr-xr-x, which is the same permissions as "Applications Drive". (You may notice that Application Drive permissions begin with an 'l' instead of 'd'. That is because Applications Drive is a link to the root directory, '/'.)

The third command just issues another directory listing of your /Volumes directory, so you can verify the new permissions, and that the 'uchg' flag is gone. And the fourth command is padding, to make it easier when you copy/paste to make sure all the commands are entered.

Many thanks to Trevor at MacOSHints Forums for the advice.

Game, Set, Match
Thank you linesmen, thank you ball boys.

 

[oldscribe]

Hi,

Good news, I was about to suggest a trip to your nearest Apple store.