Monday, 29 September 2014

How to create the bootable USB installer for OS X Yosemite ?

Apple OS X Yosemite 10.10 is a powerful and elegant operating system with the redesigned interface and new features in it.  Now, let us create a bootable USB installer for OS X Yosemite. The steps are as follows:

At first, insert the SD card or USB flash drive in the computer. Then to launch the Disk Utility, double   click on main drive, then on 'Applications' folder and lastly click on 'Utilities' folder. Select Disk Utility app from there.

Choose the drive from the device list and click on partition tab. Then select one partition from the drop down menu and give its name, size and select 'Mac OS Extended (Journaled)' from the drop down list.

Now click on the 'Options' button and you could see the partition scheme menu available right there. Then choose the radio button which is just next to GUID partition table and click ok. Now verify the changes that have been made and then click 'Apply'. A pop up window will generate asking to partition the disk finally, just then click on 'Partition' option to reflect the changes.

After the completion of the above process, the removable drive is ready  for OS X. The next step is to launch the Terminal app to unhide the hidden files which are needed to proceed the process. For that the below command is needed i.e.

defaults write AppleShowAllFiles 1 | KillAll Finder

Then, search the location where OS X file is saved and right click the installer and then  click on Show Package Content from the menu. Now, Click on Shared support which is present there and mount the installESD.dmg file. After double clicking on installESD.dmg file, we could able to see several files, out of which 2 files are needed to create the OS X installer  to the removable drive. One file is BaseSystem.dmg and  second one is Packages folder.

Now, move on back to Disk Utility app and choose the partition that we have created in above steps. Next is to select the Restore tab, drag the partition name to the destination box and also drag the BaseSystem.dmg file from Finder to the source box. Then, Click on Restore button present in the bottom  and clicking on Erase will start the process to install the drives on to the drive. And just fill the administrative credentials requested by Disk Utility to perform the task and then click on OK command to execute the changes.

After completing the task of file transfer, the drive will automatically mount in Finder. Search the installation directory to find the alias to the packages folder and just delete that alias.

And if  you want to replace that alias, then copy that Packages folder to the installation directory as done above. In this process, again the time it will generally take to transfer the file will depend on the age of the machine.

Generally, it is not a good practice to hide the files but if you want to still proceed then type the following command mentioned below to hide the files again:

defaults write AppleShowAllFiles 0 | KillAll Finder

At last the removable drive is ready to perform a clean installation of OS X Yosemite. Now, to proceed for the clean  install, power on the Mac and insert the drive. To access the boot selection menu, just hold down the option  key and choose the USB drive partition and follow the prompts to initiate the boot process.