Bootable Catalina Usb



Bootable Catalina Usb

Apple hasn’t shipped operating systems on physical media in a full decade, but there are still good reasons to want a reliable old USB stick for macOS Catalina. Luckily, it's not hard to make one—either with a handy graphical user interface or some light Terminal use. Here's what you need to get started:

  • A Mac that you have administrator access to. We've created a USB stick from both Mojave and Catalina, but your experience with other versions may vary.
  • A 16GB or larger USB flash drive or a 16GB or larger partition on some other kind of external drive. A USB 3.0 drive will make things significantly faster, but an older USB 2.0 drive will work in a pinch; 8GB drives worked for Mojave and older versions of macOS, but the Catalina installer is just a little too large to fit.
  • The macOS 10.15 Catalina installer from the Mac App Store (in High Sierra or older macOS versions) or the Software Update preference pane in Mojave. The installer will delete itself when you install the operating system, but it can be re-downloaded if necessary.
  • If you want a GUI, take a look at Ben Slaney's Install Disk Creator from MacDaddy. There are other apps out there that do this, but this one is quick and simple.

Install macOS 10.15 Catalina Using Bootable USB Flash Drive Published November 1, 2019 I purchased a used 2018 Mac mini desktop and wanted to put a fresh installation of the latest macOS 10.15 Catalina on it. MacOS 10.15, code name for Catalina, is the latest operating system shipped for Mac desktop and laptops. And it is the right time to create a bootable USB install USB based on Catalina becasue the signing certificates for old version of macOS and OS X are expired soon. A USB 3.0 drive will make things significantly faster, but an older USB 2.0 drive will work in a pinch; 8GB drives worked for Mojave and older versions of macOS, but the Catalina installer is just. For creating a Bootable USB for macOS Catalina 10.15. You are required at least a 12GB USB drive or more than that. MacOS Catalina file is approximate 16GB. A compatible system to run macOS Catalina, whether PC-Hackintosh or Mac. Now that we’re done partitioning our USB, let us proceed to set it as bootable. Create a bootable installer Download Mojave and Catali na — after downloading both, you should have Install macOs Catalina and Install macOs Mojave inside your /Applications folder.

If you want to use this USB installer with newer Macs as they are released, you'll want to periodically re-download new Catalina installers and make new install drives. Apple rolls support for newer hardware into new macOS point releases as they come out, so this will help keep your install drive as universal and versatile as possible.

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There's also one new consideration for newer Macs with Apple's T2 controller chip—as of this writing, that list includes the iMac Pro, the 2018 Mac Mini, the 2018 MacBook Air, and 2018 and 2019 MacBook Pros, though Apple keeps an updated list here. Among this chip's many security features is one that disallows booting from external drives by default. To re-enable this feature, hold down Command-R while your Mac reboots to go into Recovery Mode and use the Startup Security Utility to 'allow booting from external media.' If you're trying to install an older version of macOS, you may also need to go from Full Security to Medium Security to enable booting, but if you're just trying to install the current version of macOS, the Full Security option should be just fine. And if you're just doing an upgrade install rather than a clean install, you can run the Catalina installer from the USB drive from within your current installation of macOS, no advanced tweaking required.

The easy way

Once you've obtained all of the necessary materials, connect the USB drive to your Mac and launch the Install Disk Creator. This app is basically just a GUI wrapper for the terminal command, so it should be possible to make install disks for versions of macOS going all the way back to Lion. In any case, it will work just fine for our purposes.

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Install Disk Creator will automatically detect macOS installers on your drive and suggest one for you, displaying its icon along with its path. You can navigate to a different installer if you want, and you can also pick from all the storage devices and volumes currently connected to your Mac through the drop-down menu at the top of the window. Once you're ready to go, click 'Create Installer' and wait. A progress bar across the bottom of the app will tell you how far you have to go, and a pop-up notification will let you know when the process is done. This should only take a few minutes on a USB 3.0 flash drive in a modern Mac, though using USB 2.0 will slow things down.

The only slightly less-easy way

The Install Disk Creator is just a wrapper for the terminal command to create macOS install disks, so if you’re comfortable formatting your USB drive yourself and opening a Terminal window, it’s almost as easy to do it this way. Assuming that you have the macOS Catalina installer in your Applications folder and you have a Mac OS Extended (Journaled)-formatted USB drive (which is to say, HFS+ and notAPFS) named 'Untitled' mounted on the system, you can create a Catalina install drive using the following command.

sudo /Applications/Install macOS Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled

The command will erase the disk and copy the install files over. Give it some time, and your volume will soon be loaded up with not just the macOS installer but also an external recovery partition that may come in handy if your hard drive dies and you're away from an Internet connection. If you would like to create an install drive for a macOS version other than Catalina, just tweak the paths above to refer to Mojave or High Sierra instead.

Catalina Make Bootable Usb

Whichever method you use, you should be able to boot from your new USB drive either by changing the default Startup Disk in System Preferences or by holding down the Option key at boot and selecting the drive. Once booted, you'll be able to install or upgrade Catalina as you normally would. You can also use Safari, Disk Utility, or Time Machine from the recovery partition to restore backups or troubleshoot.