That’s why I like to make a bootable external drive for the sole purpose of installing the Mac operating system.

And if you have multiple Macs, it’s inefficient to download the new OS to each and every Mac. It’s convenient, but sometimes it can take a while for a download to finish. How to create a bootable macOS Sierra installer driveīy Roman Loyola at Senior Editor, Macworld | 1:32 PM PDTĪpple uses its App Store to distribute its software, like new Mac operating systems. This is it, you have a bootable OS X usb drive.*Quick note from Save Apple Dollars - Older OS X Images can now be downloaded directly from Apple at please right click on the image link and select “save as”. 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). Mount the thumb drive (you might need to apt-get install hfsprogs to mount an HFS filesystem). In my case (High Sierra 10.13.6), 4Gb stick was sufficient, even though createinstallmedia requires 8Gb. 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. 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. So, you'll need to find an alternative source.Ĭonvert.

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.

So, leaving it here in case somebody else will need to.

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.

Create bootable usb mac os sierra