How to repair Start-up Disk in Mac OS X?

Indeed your Mac has a start-up volume which is also called by the term boot drive. This boot drive holds the crucial Mac OS X information which is required to start the Mac machine. It is a healthy practice to segregate your entire hard drive into several logical volumes and make one of them as Mac start-up disk by installing the version of OS X on it. Every time you hit the power button to start the Mac, the OS X information is loaded from this boot drive which navigates you through the desktop. The Mac is guaranteed to come in a deadlock if this boot drive gets corrupted either logically or physically.

Can we predict a Mac hard drive failure? Yes, with the help of Mac's own in built mechanism the users, like you and me can arrive to a conclusion whether the drive may fail in near future. Use S.M.A.R.T status to generate health report of the Mac OS X hard drive & volumes. Go to Application folder and find Utilities folder to double click and launch the 'Disk Utility' application. The disk utility first tab named 'First Aid' is dedicated to scan an attached hard drive to generate its health report. Unlike other volumes, the 'Repair Disk' won't be of any help in case you are selecting to check your Mac boot drive.

Remember, to repair, defrag, or clone your Mac Start-Up disk you need to arrange secondary bootable devices like a CD-DVD, an external hard drive or a USB. When you boot on Mac from another device say an external hard drive then your primary storage device acts as an secondary device and you could then clone, defrag or repair it. Same is the case with Disk Utility that will not allow you to repair your active boot disk. But yes, you can run verify disk test but again it is noted that disk utility does not handles the verification of start-up disk efficiently. In that sense its buggy.

How to proceed then? If you received a Mac Installation disk at the time of purchase then you need to start your Mac with this disk. Start your Mac & put the disk, now hold the 'C' key till the Apple screen appears. Navigate to the 2nd screen and bring down the menu. Go to the Utilities section > Disk Utilities, choose the troubled hard drive you want to repair from the left side panel & hit the disk repair option. Once the process gets over, restart the Mac, and check if the problem is resolved. If you are lacking the Mac start-up disk then you could purchase it from the App Store or from other vendors.

What if the matter remains unresolved? It is quite obvious for the Mac disk utility to struggle with the amount of logical damage done to the hard drive. In that case you must equip yourselves with a professional Mac disk repair utility. For the boot drive, you again can select the repair tool that comes with a bootable DVD to run your Mac & repair the hard drive with the software.

Steps to begin with:
  1. Insert the boot DVD delivered with the software package & restart,
  2. Without wasting a time, press the Option key when the Mac begins to start. This will bring in the Start-up Manager displaying you few options to select the boot. Select your boot DVD to begin.
  3. The DVD will launch the Mac volume repair application from where you can select your troubled hard drive and start with its repair. Once everything is done shut off the system and boot it normally.
The Mac volume repair utility is a good choice over the disk utility to create/repair a new hard drive structure, cure Invalid Node errors etc. The repair tool may cost you few bucks but it can further prevent a costly hard drive failure.