In this case, the system will be installed on that Mac, and the installation files will disappear when the process is finished. If, however, you only want to reinstall macOS once on one computer, you don’t have to use a carrier.
You might want to keep installing files on an external drive if you think you might need to install the operating system multiple times or on different computers. In the following instructions, we will use a USB flash drive as an external carrier example. Give your disk the name of the operating system, e.g., Sierra, Mojave, Catalina. Whichever type of drive you choose, make sure that it has at least 12GB of free memory.īear in mind-when you download an installer, the disk will be reformatted to suit the operating system you’re trying to run. Use Terminal to create a bootable installerįor your external disk to run macOS, you can choose as a USB flash drive, as well as an SSD or HDD.
In this article, you’ll find detailed instructions and answers to your questions on how to make a bootable USB on Mac. You can try out the different tools for free, so download it, and see what you think. MacKeeper can do everything from finding malware to updating your apps for you. When the scan is finished, review the results, and click Fix items safely.Select Find & Fix from the menu in MacKeeper.You can do that with MacKeeper’s Find & Fix feature, which will scan your Mac for a variety of different problems. It’s a good idea to keep your Mac optimised when you’re asking to create a bootable USB drive. It’s a handy appliance-even more so if you use a small external flash drive that you can carry in a pocket. You can also use it to reinstall the operating system on a Mac that won’t startup. Such a tool allows you to install any version of macOS on multiple Apple computers easily. Why would you want to create an external boot drive for your Mac?
To boot the system from such a drive, press ⌥ immediately after rebooting.A bootable macOS (previously, OS X) install disk is a portable device containing all the necessary installation files for a selected version of macOS. Once it’s completed you can exit Terminal and remove the USB key from your OS X machine, it should now be able to bootup your ISO on another machine.
On the command line we specify the Input File using if= and the Output File using of= and dd will copy the data from input to output, block by block. Next use dd command to copy the image over: : dd if=./ of=/dev/rdisk1 bs=1m
Update 2: Specifying a blocksize of 1m will also significantly speed things up. This is accomplished by simply prepending ‘r’ to the device so that /dev/disk1 is going to become /dev/rdisk1 Update: We want to use the RAW disk device so that our copy will happen much faster because the RAW disk device provides unbuffered access to the device (See this Apple mailing list post for more info). First identify your disk device path by: : diskutil listĢ: Apple_HFS Macintosh HD 249.7 GB disk0s2 Reading Debian 6.0.7 amd64 1 (Apple_ISO : 1)…Ĭreated: /Users/evan/Downloads/debian-6.0.įinally you need to copy the image to your USB drive. Next you need to prepare ISO image by following the below command: : hdiutil convert -format UDRW -o debian-6.0.7-amd64-netinst.img debian-6.0.7-amd64-netinst.iso It is not required and you can skip it if you’d rather just unmount the volumes yourself. The purpose of doing this is mainly to ensure that the USB key is in a consistent known state and also to ensure that any volumes are not mounted by OS X. Once it’s completed you can quit out of Disk Utility.WARNING! THIS WILL DESTROY ALL DATA ON THE KEY! Select the partition section as shown below: Select the USB key (select the root device, not its partitions).Here is longer version for advanced users. This will run Burn app with appropriate settings. iso file and select ' Burn Disk Image XXX to Disc.". The easiest way is to right click on the. Answers without enough detail may be edited or deleted.
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