To install macOS or OS X from USB, you need to create a bootable install USB drive for Mac operating system. This tutorial will introduce you three ways to create bootable USB drive for macOS High Sierra, macOS Sierra, Mac OS X El Capitan, Yosemite, Mavericks and more. Follow these steps to create a bootable USB installer of El Capitan in Terminal. Connect the USB flash drive to your Mac. Give the flash drive an appropriate name. You can do this by double-clicking the device's name on the desktop and then typing a new name. OS X El Capitan PWN: Uploading.TransMac: Uploading.

• Create A Bootable Usb Mac Os El Capitan
• Install Mac Os On Usb

These advanced steps are primarily for system administrators and others who are familiar with the command line. You don't need a bootable installer to upgrade macOS or reinstall macOS, but it can be useful when you want to install on multiple computers without downloading the installer each time.

What you need to create a bootable installer

• A USB flash drive or other secondary volume formatted as Mac OS Extended, with at least 14 GB of available storage
• A downloaded installer for macOS Big Sur, Catalina, Mojave, High Sierra or El Capitan

Download macOS

• Download: macOS Big Sur, macOS Catalina, macOS Mojave or macOS High Sierra
  These will be downloaded to your Applications folder as an app named Install macOS [version name]. If the installer opens after downloading, quit it without continuing installation. To get the correct installer, download from a Mac that is using macOS Sierra 10.12.5 or later, or El Capitan 10.11.6. Enterprise administrators, please download from Apple, not a locally hosted software-update server.
• Download: OS X El Capitan
  This will be downloaded as a disk image named InstallMacOSX.dmg. On a Mac that is compatible with El Capitan, open the disk image and run the installer within, named InstallMacOSX.pkg. It will install an app named Install OS X El Capitan into your Applications folder. You will create the bootable installer from this app, not from the disk image or .pkg installer.

Use the 'createinstallmedia' command in Terminal

1. Connect the USB flash drive or other volume that you're using for the bootable installer.
2. Open Terminal, which is in the Utilities folder of your Applications folder.
3. Type or paste one of the following commands in Terminal. These assume that the installer is in your Applications folder and MyVolume is the name of the USB flash drive or other volume you're using. If it has a different name, replace MyVolume in these commands with the name of your volume.

Big Sur:*

Catalina:*

Mojave:*

High Sierra:*

El Capitan:

* If your Mac is using macOS Sierra or earlier, include the --applicationpath argument and installer path, similar to the way this is done in the command for El Capitan.

After typing the command:

1. Press Return to enter the command.
2. When prompted, type your administrator password and press Return again. Terminal doesn't show any characters as you type your password.
3. When prompted, type Y to confirm that you want to erase the volume, then press Return. Terminal shows the progress as the volume is erased.
4. After the volume has been erased, you may see an alert stating that Terminal would like to access files on a removable volume. Click OK to allow the copy to proceed.
5. When Terminal says that it's been completed, the volume will have the same name as the installer you downloaded, such as Install macOS Big Sur. You can now quit Terminal and eject the volume.
   

Use the bootable installer

Determine whether you're using a Mac with Apple silicon, then follow the appropriate steps:

Apple silicon

1. Plug the bootable installer into a Mac that is connected to the internet and compatible with the version of macOS you're installing.
2. Turn on your Mac and continue to hold the power button until you see the startup options window, which shows your bootable volumes.
3. Select the volume containing the bootable installer, then click Continue.
4. When the macOS installer opens, follow the onscreen instructions.

Intel processor

Create A Bootable Usb Mac Os El Capitan

1. Plug the bootable installer into a Mac that is connected to the internet and compatible with the version of macOS you're installing.
2. Press and hold the Option (Alt) ⌥ key immediately after turning on or restarting your Mac.
3. Release the Option key when you see a dark screen showing your bootable volumes.
4. Select the volume containing the bootable installer. Then click the up arrow or press Return.
   If you can't start up from the bootable installer, make sure the External Boot setting in Startup Security Utility is set to allow booting from external media.
5. Choose your language, if prompted.
6. Select Install macOS (or Install OS X) from the Utilities window, then click Continue and follow the onscreen instructions.

Learn more

A bootable installer doesn't download macOS from the internet, but it does require an internet connection to get firmware and other information specific to the Mac model.

Install Mac Os On Usb

For information about the createinstallmedia command and the arguments you can use with it, make sure the macOS installer is in your Applications folder, then enter the appropriate path in Terminal:

Created a bootable USB with El Capitan installer

booted from it, erased my MBP (mid 2009), clean install from USB installer

decided to use migration assistant, most apps not working plus all the clutter from pre clean install

decided to do another clean install but MBP won't boot from USB and uses the recovery version instead.

tried to get Maverick back and basically ended up with a non-working MBP that went into a boot loop

did a reinstall from MAS, ended up DLing the entire Installer again, went to bed and in the morning and 'working'

MBP again, plus all the clutter and non working apps.

Made a new bootable USB key using terminal and yes it finished and yes it said bootable at the end as well as in Disk Utilities.

However when trying to boot from USB, start+Option, or start+cmd+r still no sign of the USB stick, which i guess would leave me

with a non clean install again.

Any help, suggestions.....?

Cheers

Ralf

MacBook Pro (13-inch Mid 2009), OS X El Capitan (10.11)

Posted on Oct 4, 2015 7:57 AM