App/Script for Unmounting a Drive?

There is a third party utilityI guess you could throw into SartupItems, or System Preferences. Users & Groups > login Items.

Note: I haven't tested this myself so cannot reccomend it... or condemn it.

No, but if you're not using the internal, wear and tear shouldn't really be an issue.

The OS is built to be always on and this would provide the least wear and tear. But many folks restart their Macs daily and I've seen no evidence that the drives brick any faster than keeping them always on.

You could also physically disconnect it, if you're handy with hardware.

If the drive is never acessed and you have Put the disks to sleep when possible checked in System Preferences->Energy Saver then that drive should be spun down.

If you never use the drive at all, then set up the fstab (file system table) file to tell the system not to mount it. the file is located at /etc/fstab, and you will add a line the looks like:

UUID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx none hfs rw,noauto

that's four whitespace delimited fields which mean (respectively):

• the UUID (universal unique identifier) for the disk: read it from diskutil or from Disk Utility.app
• the mount point for the volume (none = the default, /volumes)
• the file system type (hfs, assuming it's a Mac-formatted disk)
• options (r/w = read/write, noauto = the one you're after - it tells the disk mounting daemon not to mount the disk automatically at start up)

I place the following shell script in my login items.

#!/bin/sh

#disktool -e disk0s9

diskutil unmount /Volumes/classic

Does anyone have of know of a little executable file that you can place in your startup list that when Osx starts up will unmount a disk for you?

Here's a link to a little shell script you can use to mount/unmount volumes. Use it as is or as a starting point for your own variant (e.g., adapt for a specific volume name).

A bash script to mount and unmount volumes

You could encapsulate it using Automator or Platypus.

Here is a better version of my login unmount bash script:

#!/bin/sh
#disktool -e disk0s9
# example of change string.  This is change all.
# i=${diskName//" "/"\\ "}

# debug info
export PS4='+(${BASH_SOURCE}:${LINENO}):'
set -o xtrace

ls -l /Volumes

# list of disks to unmount.
disks=("classic" "Second 80" "Ext-80" "Macintosh-HD" "Ext 500")


for diskName in "${disks[@]}"; do
  echo "diskName =${diskName}="

# sometime it takes Mac OS X awhile to mount the disks.
# try four time to try to unmount each disk.
    for ((tryCount=0;tryCount<4;tryCount++))
    do
    
      diskutil unmount "/Volumes/${diskName}" | grep "Volume /Volumes/${diskName} unmounted" 
      rc=$?
      echo "rc="$rc
      if [ $rc -eq 0 ] 
      then
        echo "unmounted  i=${diskName} tryCount="$tryCount
        break
      fi
      echo "tryCount=${tryCount} when trying to unmount ${diskName}"
      sleep 8
    done
done

rccharles, I have tried it in AppleScript Editor.app on Mac with OS X 10.8.3 (Mountain Lion), but I get an error at PS4:

Syntax Error

Expected end of line, etc. but found identifier.

How to fix it? I want to use it to automatically unmount the internal hard disks of two different iMacs (work and home) when booting from an external SSD.

Thanks.

Well, because it is a bash script. you should get textwranger and edit with that.

You may then need to mark the file as executable in terminal.

Macintosh-HD -> Applications -> Utilities -> Terminal

# press return to run the command.

chmod a+x you_script_name

There are AppleScript variants of this script. I wrote the bash script because there is a bug in the Tiger version of AppleScript. See:

https://discussions.apple.com/thread/5090542?answerId=22204831022#22204831022

Best script here:

MERGING two Scripts to Unmount disks except booting disk

https://discussions.apple.com/thread/5102909

Enjoy!

Thanks for the info.

FYI: There are still problems with unmounting disks from within an applescript when your startup drive is an external drive.

See:

https://discussions.apple.com/thread/5090542?answerId=22204831022#22204831022

Robert

Thanks for this idea. Though is seems the new way (post ML?) is to runs "sudo vifs" and edit that file. The format is the same though and this worked perfectly for preventing the HTC bloatware on my phone from mounting a volume every time I plugged in to charge. You have my thanks.