How to create OS X 10.10 Yosemite bootable installation flash drive

by on

Introduction

Macs keep their installation and recovery partitions so when needed, users can comfortably restore OS X back to default. However when hard drive malfunctions and is replaced, you will also lose this recovery partition. Mac also contains recovery option in its UEFI and it is able to download installation packages through Internet, but if you have problems with Internet connection (slow connection, WEP security on WiFi), the USB bootable flash drive is the best alternative how to restore your system.

The fastest way how to restore the system is to use a bootable installation flash drive and this article will show you how to create such installation disk with OS X 10.10 Yosemite.

Three ways how to create OS X USB installation drive:

Preparation - get OS X Yosemite installer and USB flash drive

First you need to have Yosemite installer (Install OS X Yosemite.app in Applications folder). If you don't have the installer in Applications folder, you can download it from Mac App Store.

Download OS X Yosemite from App Store

Also you need flash drive with at least 8 GB capacity, formatted with a GUID Partition Table which is named Untitled by default like is shown on our screenshot. You can of course rename it to whatever you need but you will then need to alter the commands accordingly.

Create GUID formatted flash drive in Disk Utility

To boot from flash drive you need to press and hold Option (ALT) Key on keyboard through boot up the Mac.

How to create installation USB drive with createinstallmedia tool

The createinstallmedia is a command line tool integrated to OS X Yosemite installer. It is the easiest way how to create USB installation flash disk with OS X Yosemite.

Open the Disk Utility and format flash drive with a GUID Partition Table and check it out in the Finder if Install OS X Yosemite.app is in your /Applications folder.

Now open the Terminal and type the following command:

sudo /Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled --applicationpath /Applications/Install\ OS\ X\ Yosemite.app --nointeraction

In our case "Untitled" is the name of USB flash drive! Replace "Untilled" by name of your flash drive.

Wait a few minutes and your Yosemite installation USB drive will be prepared.

create OS X installation media with createlinstallmedia tool

To install OS X Yosemite ► restart computer ► hold the Option key and select Installation USB drive from the menu.

How to create installation USB drive with Terminal commands

Format your USB flash drive with a GUID Partition Table and named it Untitled. Download Install OS X Yosemite.app from App Store, if you do not have it your /Applications folder already.

Open Terminal and type the following sequence of commands:

sudo hdiutil attach /Applications/Install\ OS\ X\ Yosemite.app/Contents/SharedSupport/InstallESD.dmg

sudo asr restore -source /Volumes/OS\ X\ Install\ ESD/BaseSystem.dmg -target /Volumes/Untitled -erase -format HFS+

sudo rm /Volumes/OS\ X\ Base\ System/System/Installation/Packages

sudo cp -a /Volumes/OS\ X\ Install\ ESD/Packages /Volumes/OS\ X\ Base\ System/System/Installation/Packages

sudo cp -a /Volumes/OS\ X\ Install\ ESD/BaseSystem.chunklist /Volumes/OS\ X\ Base\ System

sudo cp -a /Volumes/OS\ X\ Install\ ESD/BaseSystem.chunklist /Volumes/OS\ X\ Base\ System

sudo cp -a /Volumes/OS\ X\ Install\ ESD/BaseSystem.dmg /Volumes/OS\ X\ Base\ System

hdiutil detach /Volumes/OS\ X\ Install\ ESD

Now wait until your bootable installation flash drive with OS X 10.10 Yosemite is prepared.

Create USB installation flash drive with OS X Yosemite with Terminal

To install OS X Yosemite ► restart computer ► hold the Option key and select Installation USB drive from the menu.

How to create installation USB drive with Disk Utility and Finder

Some files that you need to create USB flash drive is hidden. To view hidden files in Finder open terminal and use command:

defaults write com.apple.finder AppleShowAllFiles 1 && killall Finder

Open Finder ► Applications ► Install OS X Yosemite.app ► right click ► Select Show Package Contents option.

Show Package contents

Navigate to Contents/SharedSupport ► Mount InstallESD.dmg file

Install ESD file

Open OS X Install ESD archive in Finder and mount BaseSystem.dmg archive

Yosemite installation base file

Connect USB drive and open Disk Utility (/Applications/Utilities)

Select the USB drive from the list of disks, select Restore option and pick Select OS X Base System archive as a source and USB flash drive as the destination. When ready click on Restore button.

Apple Disk Utility

After the Restore process is finished, open Finder ► open USB drive (OS X Base System) ► go to the System/Installation folder and select Packages file and delete it.

Packages file

Open OS X Install ESD volume in Finder, select Packages folder and copy them to System/Installation folder on USB drive.

Packages folder

Also copy BaseSystem.chunklist and BaseSystem.dmg files from InstallESD.dmg volume to root of USB flash drive (OS X Base System).

Other Yosemite installation files

Now your Yosemite installation USB drive is prepared and ready for use.

To install OS X Yosemite ► restart computer ► hold the Option key and select Installation USB drive from the menu.

Related software and links:

Apple Disk Utility icon

Apple Disk Utility    Apple macOS / Mac OS X platform
A disk mounting utility from Mac OS X

 
Apple Finder icon

Apple Finder    Apple macOS / Mac OS X platform
Default file manager in macOS

 
Mac OS X icon

Mac OS X    Apple macOS / Mac OS X platform
Unix-based operating system for Apple Mac computers

 

Did this entry help you?
If the information in this article helped you, please share it with your friends!

Subscribe to File-Extensions.org and get our news everywhere!

RSS

Add new comment about “Create OS X Yosemite USB bootable drive

Go to:
Article related software
Add comments...

Follow us!

Enter any file extension without dot (e.g. pdf)
Search for file extension details and associated application(s)

RSS feed