This is it, you have a bootable OS X usb drive. Creating the installer will erase all data on the USB drive, so make sure. From the first iso, obtained on step 3, copy BaseSystem.chunklist and BaseSystem.dmg on the thumb drive (actually, the latter might not be necessary - but it worked for me at this step and I stopped experimenting). To create a bootable macOS High Sierra USB installer, you need a USB 2.0 or USB 3.0 drive with a capacity of at least 8GB.
#How to make a bootable usb mac os sierra install
Mount the thumb drive (you might need to apt-get install hfsprogs to mount an HFS filesystem). Start the computer and press the boot key like F10, F12, etc. Connect it to the computer on which you want to install MacOS. In my case (High Sierra 10.13.6), 4Gb stick was sufficient, even though createinstallmedia requires 8Gb. Close Etcher and eject your USB drive or SD card. This can be a hard drive, an SSD, or a USB stick. Once done, turn your USB into a bootable drive. iso as well ( dmg2iso -i BaseSystem.dmg -o BaseSystem.iso)Ĭopy it to a thumb drive: dd if=BaseSystem.iso of=/dev/sdX BS=1M. You need a Mac-formatted drive big enough to hold the installer and its data - 12 GiB. iso įind BaseSystem.dmg in the mounted image. You can do it from GUI (right click, "Open with disk image mounter") or something like mount -o loop. Release the Option key when you see a dark screen showing your bootable volumes. Restart your computer, and then immediately press and hold the Option (Alt) key. Ensure that the device is compatible with the version of macOS you’re installing. So, you'll need to find an alternative source.Ĭonvert. Plug the bootable USB into a Mac that is connected to the internet. This question on apple support has all the links, but they are only accessible from OS X (if you had access to a live OS X at this point - you probably would've just used createinstallmedia already, right?). Unlike El Capitan, High Sierra only needs BaseSystem.dmg, which also has enough free space to boot - so, the process overall can be simplified a bit. Step 1: Download macOS Catalina DMG for Windows Step 2: Partition USB disk on Windows to make it bootable on Mac Step 3: Make bootable macOS Catalina USB. So, leaving it here in case somebody else will need to.
#How to make a bootable usb mac os sierra iso
I recently had to make a High Sierra 10.13.6 bootable USB drive, and the process turned out a bit more involved that just dd-ing the dmg2img-generated ISO to a thumb drive.