Apple released the new Mac OS X 10.10 Yosemite in the Mac App Store for everyone to download and install for free on October 16th, 2014, but downloading a 5+ GB file for each of your computers will take some serious time. The best thing to do is download it once and create a bootable install USB. Apple released the new Mac OS X 10.10 Yosemite in the Mac App Store for everyone to download and install for free on October 16th, 2014, but downloading a 5+ GB file for each of your computers will take some serious time. The best thing to do is download it once and create a bootable install USB drive from the file for all of your Macs.
The Mac App Store is the default way to upgrade or install macOS, but it doesn’t work for everyone. Maybe you’ve got multiple Macs and a limited amount of bandwidth, and don’t want to download the entire operating system for every system. Or maybe you’re looking to install the operating system from scratch. Whatever your reason, installing macOS from a USB drive isn’t hard. You just need a few things:.
An 8GB USB drive. This process will overwrite the entire drive, so back up anything stored on it. If your drive is larger than 8GB, and you’d like to use the rest of the drive for something else, you could: just create an empty, 8GB partition for the installer. Access to at least one working Mac with access to the Mac App Store. This can be a friend’s machine if necessary. Once you have those things we can get started. First, Download macOS From The Mac App Store To begin, you need the installer for whatever version of macOS you want on a thumb drive.
Head to the Mac App Store. If what you’re looking for is the latest version of macOS, search for that operating system and click the “Download” or “Install” button. The download will take a while, so make sure your Mac is plugged in and has a consistent connection to the Internet.
The installer will load when the process is done; simply close the window, then head to your Applications folder to confirm the installer is there. If you don’t want the latest version of macOS, searching the App Store won’t help you. Instead, you’ll have to head to the “Purchases” tab in the installer and scroll down until you find the version of macOS you want on your thumb drive. You will only find versions you’ve previously downloaded here. Click the “Download” button to the left of the release you want to install, and your Mac will download it. Again, the installer will launch when the download is complete; close the window when this happens. We’re now ready to create our disk.
There are two ways to do this: one with third party software, and another with the Terminal. The Easy Way: With DiskMaker X The simplest way to create a boot USB drive is to and use it to create your drive.
Generally, the latest version supports only the latest version of macOS; if you want to install something older than macOS High Sierra, check the and download one that’s compatible with your chosen operating system. Installing is simple: just mount the DMG, then drag the program to your Applications folder. Start the program and it should find the installer you downloaded above. If you’ve put the installer somewhere besides the Applications folder, you can direct DiskMaker X to the file manually. After that, you’ll be asked which disk you’d like to use. Choose the drive or partition, knowing that it will be completely overwritten.
Once you authorize the action, DiskMakerX will mostly run in the background. When the process is done you’ll hear a loud lion roar (seriously, it freaked me out), and you’ll see the completed drive. Diskmaker X also offers a variety of utilities, which can come in handy. The Terminal method, outlined below, does not include these. The (Slightly) Harder Way: With the Terminal If you’d rather not rely on a third-party tool to create your disk, Apple offers a built-in Terminal-driven method. To summarize: there is a script, called createinstallmedia, included in every macOS installer, and we’re going to run it.
![Boot Boot](http://cdn.osxdaily.com/wp-content/uploads/2015/06/finished-windows-10-bootable-usb-install-drive.jpg)
First, insert your thumb drive and give it a name—I’m using “Installer” for the purposes of this writeup, but make note of whatever name the drive has. Next, let’s find the installation script.
Open the Terminal, which you can find in Applications Utilities, and run the following command. Note that the exact command will vary depending on which version of macOS you’re trying to install; this one is specific to Sierra.
Sudo /Applications/Install macOS High Sierra.app/Contents/Resources/createinstallmedia -volume /Volumes/Installer -applicationpath /Applications/Install macOS High Sierra.app In case you’re curious, here’s how this breaks down:. To run the command as root. This means the command must start with sudo.
/Applications/Install macOS High Sierra.app/Contents/Resources/createinstallmedia is the location of the script. Obviously, change “High Sierra.app” to whatever version you’re installing. To provide the application with a path to the volume that will be overwritten. In our case, this is /Volumes/Installer. To provide the application with a path to the installer package. For macOS Sierra, this is /Applications/Install macOS High Sierra.app You will be asked to confirm that you’re ready for the disk to be deleted: Yet “y”, then Enter, and the process will begin.
First the disk will be deleted, then the entire installer will be copied to your disk. The process will take a while, but when it’s done you’ll have a bootable drive with the installer.
Notice that the Utilities folder, offered by DiskMaker X, is not here. The command above is specifically for High Sierra (and a disk named “Installer.”) Previous versions of macOS will have slightly different names.
The reason many people want to have a bootable is to create clean installs: that is, to install Lion on a freshly formatted hard drive that doesn't contain any previous OS. The other major reason to want a bootable Lion installer is for emergency booting. It's true that Lion creates a bootable that you can use for troubleshooting. But the Recovery partition is only usable if your drive is in basic working order.
If your drive has a corrupt partition table, or you've replaced the hard drive, then the Recovery partition is downright useless. OS X Lion installer. 8 GB USB flash drive. You can use a larger drive if you wish, but more important than the size of the flash drive is its speed.
If you're buying a new flash drive just for Lion, I recommend buying one of the fastest available. While slow (read: inexpensive) flash drives will work fine, you'll find that both the time it takes to create the bootable flash copy of the OS X Lion installer and the time it takes to install Lion on a target drive, will be somewhat long. Some free time. The creation time varies by the speed of the USB flash drive, but plan on 30 minutes to over an hour.
![How to boot usb on mac How to boot usb on mac](/uploads/1/2/5/6/125602259/453009337.png)
Insert the USB flash drive into your Mac's USB port. Launch Disk Utility, located at /Applications/Utilities. In the Disk Utility window, look for the flash drive in the list of attached devices. Look for the device name, which usually appears as the drive size followed by the manufacturer's name, such as 16 GB SanDisk Cruzer.
Select the drive (not the, which may appear below the drive manufacturer's name), and click the Partition tab. Use the Volume Scheme drop-down window to select 1 Partition. Enter a name for the volume you're about to create. I prefer to use the name that Apple originally assigned to the Lion installer image that we'll copy in a later step, so I enter Mac OS X Install ESD as the volume's name. Make sure the Format drop-down menu is set to Mac OS X Extended (Journaled). Click the Options button, select GUID as the Partition Table type, and click OK.
Click the Apply button. Disk Utility will display a sheet asking if you're sure you want to partition your USB flash drive. Click Partition to continue.
Once Disk Utility finishes formatting and partitioning the USB flash drive, quit Disk Utility. Open a Finder window and navigate to /Applications/. Right-click on Install OS X Lion (this is the installer you downloaded from the Mac App Store), and select Show Package Contents from the pop-up menu. Open the Contents folder. Open the SharedSupport Folder. Within the SharedSupport Folder is an image file called InstallESD.dmg. Right-click the InstallESD.dmg file and select Copy from the pop-up menu.
Close the Finder window. Right-click in a blank area of the desktop, and select Paste Item from the pop-up menu. This will create a copy of the InstallESD.dmg file. Clone the InstallESD.DMG File to the Flash Drive. Launch Disk Utility, if it's not already open. Click the flash drive device (not the volume name) in the Disk Utility window.
Click the Restore tab. Drag the InstallESD.dmg from the device list to the Source field. Drag the Mac OS X Install ESD volume name from the device list to the Destination field. Make sure the Erase Destination box is checked. Click Restore. Disk Utility will ask if you're sure you wish to perform the restore function. Click Erase to continue.
You may be asked for your administrator account password; supply the necessary information and click OK. The clone/restore process can take a bit of time. Once the process is complete, you can quit Disk Utility. Using the Bootable Flash Drive.