macOS Recovery is part of the built-in recovery system of your Mac. You can start up from macOS Recovery and use its utilities to recover from certain software issues or take other actions on your Mac.
How to start up from macOS Recovery
This should create a working OS on 'Macintosh HD', and will also create the 'Recovery HD' and 'BootEFI' partitions. After doing that, create the fusion drive using the diskutil core storage commands (join the 'Macintosh HD' partition and the SSD together, leaving the BootEFI and Recovery Partition undisturbed.
Sep 30, 2015 Presumably you have already made the USB flash drive into a Mac compatible format with Disk Utility, if not you can follow the directions here to format a drive for Mac OS X compatibility HFS+. When you’re ready, plug the USB / flash drive into the Mac with the OS X. May 05, 2015 The Assistant will now create your external Recovery drive. Once you have a recovery disk, you can recover your Mac when trouble strikes. To recover your machine, simply boot or reboot holding down “Command + R” and your Mac will search, first the recovery partition, then the Internet and any external drives you have made with Recovery. Drag-and-drop the Mac OS X Install Drive disk into the Source box At the bottom right-hand corner of the screen and click the Restore button Disk Utility will restore the OS X Install DVD or disk image to the USB drive; this process may take anywhere from 20 minutes to an hour depending on how quick the Mac is. (OS X Recovery lets you repair your drive and reinstall OS X, but to perform the latter task, you must wait—each time you use it—for the entire 6GB of installer data to download.
- Turn on your Mac and immediately press and hold these two keys: Command (⌘) and R. Need help?
- Release the keys when you see an Apple logo, spinning globe, or other startup screen.
- You might be prompted to enter a password, such as a firmware password or the password of a user who is an administrator of this Mac. Enter the requested password to continue.
- Startup is complete when you see the utilities window:
- After starting up from macOS Recovery, select a utility, then click Continue:
- Restore From Time Machine Backup:Restore your Mac from a Time Machine backup.
- Reinstall macOS: Download and reinstall the Mac operating system.
- Get Help Online: Use Safari to browse the web and find help for your Mac. Links to Apple's support website are included. Browser plug-ins and extensions are disabled.
- Disk Utility: Use Disk Utility to repair your disk or erase your disk or other storage device.
Additional utilities are available from the Utilities menu in the menu bar: Startup Security Utility (or Firmware Password Utility), Network Utility, and Terminal.
- To quit macOS Recovery, choose Restart or Shut Down from the Apple menu . If you want to choose a different startup disk before quitting, choose Startup Disk from the Apple menu.
If you can't start up from macOS Recovery
If your Mac can't start up from its built-in macOS Recovery system, it might try to start up from macOS Recovery over the Internet. When that happens, you see a spinning globe instead of an Apple logo during startup:
To manually start up from Internet Recovery, press and hold either of these key combinations at startup:
- Option-Command-R
- Shift-Option-Command-R
Learn more
If startup from Internet Recovery is unsuccessful, you see a globe with an alert symbol (exclamation point):
In that case, try these solutions:
- Make sure that your Mac can connect to the Internet. If you're not prompted to choose a Wi-Fi network during startup, move your pointer to the top of the screen, then choose a network from the Wi-Fi menu , if available.
- Press Command-R at startup to try using the built-in Recovery system instead of Internet Recovery.
- Connect to the Internet using Ethernet instead of Wi-Fi, or vice versa.
- Connect to the Internet from a different Wi-Fi or Ethernet network. Your network configuration might not allow the Internet access that macOS Recovery needs.
- Try again later, because the issue might be temporary.
- Start up from another disk or volume, if available, or use a bootable installer to reinstall macOS.
If you still need help, please contact Apple Support.
Beginning in Lion (10.7), there's a new feature in Mac OS X to assist you if things go really wrong, since you can't boot from disk anymore. This new feature is called Recovery, and it gives you a way to start 'from scratch' if you need to rebuild your Mac.
There are a couple of methods for doing this, which both lead to the same place: A USB drive (8GB or larger), safely stashed in a drawer, which has a bootable OS on it, as well as an installer to put that OS on a hard drive.
First up is the 'official' method, a utility introduced with Mavericks, called Recovery Disk Assistant. This works with Lion, Mountain Lion, and Mavericks, all the versions of Mac OS that were distributed via the Mac App Store.
Using this method is pretty straightforward: download the Recovery Disk Assistant, plug in that USB drive, and follow the prompts. After a little while you will have a bootable backup of your OS.
An alternate method that dates back to the release of Lion is Disk Maker X, formerly known as Lion Disk Maker. This is a nice wrapper for a set of Applescripts that will also create a USB drive to back up from. This was the nicest option before Apple built a utility of its own. It works much the same way as Apple's too, launch the app and follow the prompts and you end up with a USB drive you can boot from.
Mac Os X Create Recovery Drivers
Keep in mind you can't install an older OS than your computer shipped with, but otherwise to use this newly minted installer all you have to do is plug in the USB drive, and hold down the Option key while the machine boots. This will give you your boot drive options, then choose the USB stick and you're all set.