Installing Yosemite from a bootable drive comes in handy if you want to do a clean install - wiping your hard drive and installing a fresh copy of the operating system, for example, or if you're installing the software on multiple Macs and don't want to have to download it each time.
Which mac are you wanting to download Mac OS X Yosemite on, model and year.
Some macs that came preinstalled with an OS newer than Mac OS X Yosemite cannot
The disk that you are booted to at the time. Not any internal or external disk that you want to eventually install Yosemite on, that is for later.) Create a bootable USB installer disk using the Install OS X Yosemite.app. In the Applications folder and the createinstallmedia command in the Terminal app. Read the instructions here, How to create. Install Yosemite from the installation disk. Create the macOS X 10.10.5 Yosemite Install Disk from official sources As the hdiutil tool is proprietary, we do not have the choice to use a macOS to create the ISO file. Locate the file named Install OS X Yosemite, and then right-click the file and select Show Package Contents. Open the Contents folder, then open the Shared Support folder. Here you will find the disk image that contains the files you need to create a bootable installer. Double-click the InstallESD.dmg file. Doing so will mount the InstallESD.
do the conversion from InstallOSX.pkg to Install OS X Yosemite.app.
If the 'donor' mac is too new to convert the InstallOSX.pkg to Install OS X Yosemite.app
do you have a copy of the Snow Leopard DVD install disk.
If the mac running Big Sur is the right age to create the Yosemite installer app
click on the link below.
Go to Download macOS and click on OS X Yosemite 10.10
this downloads InstallMacOSX.dmg to your Downloads folder.
The next section can only be done on a mac that is capable of running Yosemite.
This includes macs that have the potential to run Yosemite but have been upgraded to a newer OS.
A mac that came preinstalled with an OS later than Yosemite will refuse to do the next bit.
When downloaded open to InstallMacOSX.pkg, double-click on
that and an installation window will open, this does not install Yosemite
but converts the InstallMacOSX.pkg to the Install OS X Yosemite.app which
you will find in your Applications folder.
(If the installation window asks which disk you want to install to, you must pick
the disk that you are booted to at the time. Not any internal or external disk that
you want to eventually install Yosemite on, that is for later.)
Create a bootable USB installer disk using the Install OS X Yosemite.app
in the Applications folder and the createinstallmedia command in the Terminal app.
Read the instructions here,
Aug 28, 2021 6:40 AM
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.
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:
Y
to confirm that you want to erase the volume, then press Return. Terminal shows the progress as the volume is erased.Determine whether you're using a Mac with Apple silicon, then follow the appropriate steps:
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.
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: