Can you boot a mac from a usb drive

Now you just need to set it up as you normally would. It's ready to go. Next time you start your computer, it might revert back to booting from your internal hard drive. You've got two options to boot to your external drive. Click the lock and enter your password to change the settings. Select your USB drive from the list and click Restart.

The second method is to turn on your computer and hold down the Option key. After a short delay you'll see a list of available drives, including both internal and external ones. Choose the external drive and hit Enter to continue booting.

Both of these methods set the external drive as the default. Of course, you can only boot from an external drive when it's connected. Therefore you can simply unplug it whenever you want to boot to your internal drive instead.

There's one final and important point to know. When running macOS off an external drive, you still have to shut it down in the normal way. Don't just whip out the USB drive, or try to eject it somehow.

This could cause you to corrupt your data. You need a full computer reboot to switch from one drive to the other. The entire process of setting your Mac to boot from USB should take around half an hour at most. Install it on a fast SSD and you've got a usable dual-boot system on your hands.

Or you could install macOS on a flash drive, stick it in a drawer, and keep it for emergencies. Booting your Mac from a USB drive gives you a way to fix any boot problems your computer experiences. But it isn't the only solution. We've got a complete guide on how to fix Mac boot problems that should help get you up and running no matter what is wrong.

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In that time he has contributed to countless publications and produced copywriting work for large tech companies. If you are unable to select a different startup disk, it's possible that your disk is not showing up in Startup Manager. If you try Method 1 above but don't see your USB drive listed there, it could mean one of the following problems:. You have to use USB 2.

That means you won't be able to see it in the Startup Manager so, of course, you won't be able to boot from it. This will put your Mac into Recovery mode. To do this, use Method 1 to access Startup Manager. Once you are there, press Option-Shift-Command-Period. You should now be able to see the USB drive. This is not exactly a problem as much as a feature. These two methods and the troubleshooting tips should allow you to boot from USB or in Recovery Mode so you can then isolate the problem that's preventing your Mac from booting up normally.

Petty is editor in chief at UUByte and writes various topics about Windows and Mac to help people make the most of current technology. Copyright - UUbyte. This will let you boot your Mac from a different source if it won't work normally, and makes installs on multiple machines easy. Creating a bootable USB drive and using it to reinstall to macOS is a bit of a lengthier process as opposed to simply updating macOS from the Software Update section of the System Preferences, but it has its benefits.

Creating a bootable USB disk allows you to install or update macOS on multiple systems without having to download the installer on each Mac. This can save quite a bit of time, considering the most versions of macOS have an installer size of 12GB. You can also use the built-in recovery tools that come with the macOS installer to troubleshoot and fix different kinds of issues. These include regaining access to a Mac that refuses to boot or recover files that seem to be lost.

Another benefit of using a bootable disk for a macOS installation is that you can perform a clean install. A clean install allows you to get rid of junk apps and files that may have accumulated over time. This almost always results in a Mac running faster after a clean install, since macOS has started over with a clean slate. Simple Tips to Speed It Up. USB flash drives are cheaper than ever, so you won't have to spend much on this task. Stay away from cheap drives with suspiciously high storage on sites like eBay.

Those drives often have their firmware hacked to report a false size to your operating system. Not only will the transfer speeds be painfully slow, but using them may also result in loss of data or even a damaged USB port.

Also, check to see what ports you have on your Mac. It's best to go with a USB 3. You can only create a bootable installer for macOS on a Mac. If you're using a flash drive that already has data on it, make sure to back up any important files now, as you're going to erase everything in a moment. Open Finder. You should see your flash drive under the External section in the left pane. After selecting it, click on the Erase button along the top.

Choose a friendly name which you'll use later , and make sure to choose Mac OS Extended Journaled for the format.

Finally, click Erase. Apple has changed the method for downloading versions of the operating system of macOS.