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How to make a bootable macOS installer on an external drive

How to make a bootable macOS installer on an external drive

In this article, we’ll undergo the steps required to create a bootable installer of the Mac working system, whether or not to install the most recent model of macOS on a number of Macs; install the most recent macOS beta, carry out a clear set up of the macOS; or simply to be ready with an emergency drive in case your Mac is having points and you do not need to join to the web or in restoration mode, or entry restoration mode.

If you need to know how to make a bootable set up of macOS Catalina, macOS Mojave or an older model of Mac OS X or macOS, you have come to the best place.

You may use your bootable installer to install the macOS on a separate quantity of your onerous drive (or on a partition should you’re utilizing an older model of the Mac OS), it is also a hassle-free method to roll again to an older 1 model of MacOS X or MacOS. It’s additionally a nice choice should you find that putting in the installer has taken a very long time and you do not really feel like downloading it a number of occasions on a number of Macs within the subsequent few days. Once if sufficient!

Fortunately, making a bootable set up of the Mac working system turned a lot simpler when Apple launched OS X Mavericks in 2013. With that model of Mac OS X, and all variations since then, it was potential to use the Terminal command createinstallmedia to create a bootable installer of the macOS, we’ll present you how on this article. Before we do this, we’d like to get the set up data. If you have already got them, you’ll be able to instantly begin creating a bootable installer and creating set up code to use.

Read this if you’d like to run macOS from an external drive, which is barely completely different.

Install bootable macOS

What you want to create a bootable set up drive

There are 2 essential belongings you want to make your bootable set up. The complete course of doesn’t take lengthy.

A 12 GB Flash Drive (a minimum of!)

We advocate a 12 GB (or more) drive, this can be more than you want, the Mojave beta installer was 5.68 GB whereas the High Sierra installer was 4.3 GB.

We advocate a Flash reminiscence stick as it’s sooner. You additionally profit from USB 3 or USB Type C – this can be your solely alternative when you have a newer Mac.

If you may have any Data on the disk that you really want to use, you will want to switch it to 1 other disk or buy a new disk as it is going to be fully formatted and erased.

Theset up data

Find installation files

Depending on which model of macOS you’re utilizing and the model you need to install, you may get the set up data from Software Update in System Preferences, the Mac App Store, otherwise you want to get them from elsewhere.

The Mac App Store might be the better choice, however, there should be points relying on which model of macOS your machine is working, and should you’re hoping to seize older install data that may be a ache, we’ll present you how to grow old variations right here can get from macOS.

Obviously, you will want an web connection to download the software program and you might want it whereas putting in the model of macOS if it wants to check for firmware or verify iCloud credentials.

How to get macOS set up data

As we stated, how you get the set up data relies upon on the model of macOS you are at present utilizing and the model you need the installer for. Below we’ll take a look at how to get Catalina installers and how to grow old variations of macOS and even Mac OS X. We have a particular article on how to download outdated Mac OS X and macOS variations.

Get Catalina set up data

Follow these steps to download the installer for the new macOS that arrived in October 2019, macOS Catalina.

  1. If you’re utilizing Mojave on your Mac, go to System Preferences> Software Update.
  2. Wait whereas your Mac searches for the most recent macOS replace.
  3. If it tells you that the working system replace is accessible for download, go forward and download the set up data.

But cease earlier than clicking to install – you want to copy this set up file earlier than putting in it on your Mac if you’d like to entry it to create the boostable installer. Instructions for that under.

How to get Catalina – should you use Catalina

If you’re already utilizing Catalina, Software Update is not going to present you the software program obtainable for download, however, you’ll be able to nonetheless download the set up data from the Mac App Store.

  1. Open the Mac App Store.
  2. Visit the Catalina web page, you’ll be able to click on this link to Catalina within the Mac App Store.
  3. Now should you click on on Get your Mac will provide to download the installers.

Again, do not click on install as you will want the set up file for the following stage of this tutorial …

Get macOS Catalina beta set up data

If you are searching for an installer for the Catalina Beta, signal up for the Beta if you’d like to take a look at and take a look at out the new Catalina options earlier than they’re launched to most of the people.

We take a nearer take a look at how to get and install the Catalina beta right here. We have the code you want to install the Catalina beta by way of an external drive under.

How to grow old macOS set up data

With macOS Catalina, Mojave, or High Sierra put in, getting the set up data for older variations of macOS is a bit tough. This is as a result of when High Sierra launched, Apple stopped making older variations of the working system obtainable for download from the Mac App Store.

Fortunately, it nonetheless can, and we’ll clarify how to get outdated variations of macOS right here.

However, should you’re not utilizing any of these newer variations of macOS – or you may have entry to a Mac – observe these steps to download the set up data from an older macOS.

Here’s how to get the macOS set up data should you’re searching for an older model of the macOS and are not at present utilizing Catalina, Mojave, or High Sierra.

  1. Launch the Mac App Store on your Mac.
  2. Search for the model of macOS you need to have within the retailer (should you’ve beforehand downloaded the model search below your Purchases tab).
  3. Click the download button. If you may have already put in this model of macOS, you will notice a message that the model of macOS is already put in on this computer. Click Continue to verify that you just nonetheless need to download the complete installer.

    Download macOS from Mac App Store

  4. Your Mac downloads the installer to your Applications folder. This course of might take a whereas relying on the pace of your connection and whether or not you’re utilizing a wi-fi community. It took us about 10 minutes over Ethernet.
  5. If it begins mechanically after downloading, ceaseyou do not need to begin the set up course of on your Mac as a result of it removes the installers – and these are the installers you want. When it opens, shut the installer.
  6. You can find the set up data in your Applications folder, which you’ll entry via the Finder.

How to create a bootable macOS installer

Now that you’ve got the set up data, we are able to transfer on to creating the bootable installer.

Please notice, the createinstallmedia technique described right here doesn’t work below OS X 10.6 Snow Leopard or earlier – it requires OS X 10.7 Lion or later. Also, the processes have modified barely since Mavericks, so should you’re wanting to install 1 of many “Cat” variations of Mac OS X, it is best to read this older article as an alternative.

Since Mavericks, creating a bootable set up of macOS requires a single command in Terminal. The createinstallmedia command permits you to create a bootable copy of an installer on any drive related to your Mac.

Note that the createinstallmedia command erases every little thing on your external drive, so make certain it would not include something you want.

These are the directions to observe should you want the macOS High Sierra installer, however, should you wished a completely different model of a post-Mavericks working system or the Mojave beta, the directions will likely be related.

  1. Connect an external drive with a minimum of 8 GB of area (ideally 12 GB) as that is how a lot the installer wants.
  2. Start Disk Utility (press Cmd + Spacebar and begin typing Disk Utility).
  3. Before this subsequent step, bear in mind: should you’re utilizing High Sierra or newer, click on the Show drop-down record under the decrease shut buttons. Choose Show All Devices from the choices. Now you will notice the external root drive subsequent to the quantity under it.
  4. Select the foundation drive within the sidebar (the following step will not do should you solely choose the quantity).
  5. Click on Clear.
  6. Choose Mac OS Extended (Journaled) because the format.
  7. Choose GUID partition map because the scheme.
  8. Your disk is named Untitled by default, you’ll be able to identify your disk like “macOS” or “USB”. (Note that it is best to solely exchange the time period USB within the Terminal command with the identify of your disk).
  9. Click on Clear.
  10. Wait whereas Disk Uitlity creates the partition and units up the disk (this will take a jiffy).
  11. Then click on Done.
  12. Open Terminal (the best method is to press cmd + spacebar after which kind Terminal).
  13. Copy the next textual content corresponding to the model of macOS you install in Terminal, yow will find the textual content within the part under.
  14. Click Enter / Return.
  15. Terminal asks for a password. This is your person password. Note that you just will not see any characters seem as you kind it in, that is effective. After coming into your password, press Enter.
  16. Terminal warns that it is about to erase the drive (so make certain nothing essential was on it!). To proceed, press Y after which Return. The course of might take a while, you will notice “Disk Erase: 0% … 10% … 20% … 30% … 100% …

  17. Now Terminal will spend a jiffy copying the set up file to your disk. “Copy installation files to disk … Copy complete” and so on will seem within the Terminal window.
  18. When Terminal has completed copying the installer, you will notice the phrases Copy Complete and Done seem.
  19. Now you may have the installer on the external drive you can use to install a number of copies of macOS. Connect the external drive to the Mac on which you need to install the macOS.
  20. Boot the Mac and maintain down the Option / Alt key throughout startup.
  21. Your Mac will show the Startup Manager, click on on your external drive to choose it because the startup disk. Your Mac will boot into restoration mode.
  22. Click Install macOS after which click on Continue. The model of macOS ought to now be put in on your Mac.

You may run the Mac working system instantly from an external drive as an alternative of out of your built-in startup disk, which is beneficial when testing new variations of Mac OS. However, the method is completely different from the 1 described above, and we’ll cowl it right here: Learn how to run macOS on an external onerous drive right here.

Note that older variations of macOS used “application path” whereas newer ones did not – should you use the command you’re going to get an error (we’ve got the code for all variations of macOS and Mac OS X under).

createinstallmedia instructions

The createinstallmedia command will fluctuate barely relying on which model of macOS you need to use.

Note MyVolume might have a completely different identify for you, for instance it might be USB or 1 thing related. Check in Disk Utilities, it’s the identify of the external disk you’re utilizing.


sudo / Applications / Install macOS –volume / Volumes / MyVolume

Catalina beta

sudo / Applications / Install macOS Catalina –volume / Volumes / MyVolume –nointeraction –downloadassets


sudo / Applications / Install macOS –volume / Volumes / MyVolume

High Sierra

sudo / Applications / Install macOS High –volume / Volumes / MyVolume


sudo / Applications / Install macOS –volume / Volumes / MyVolume –applicationpath / Applications / Install macOS

the captain

sudo / Applications / Install OS X El –volume / Volumes / MyVolume –applicationpath / Applications / Install OS X El


sudo / Applications / Install OS X –volume / Volumes / MyVolume –applicationpath / Applications / Install OS X


sudo / Applications / Install OS X –volume / Volumes / MyVolume –applicationpath / Applications / Install OS X

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