Change Startup Disk settings on Mac
On your Mac, use Startup Disk settings to change your startup disk. You can start up your Mac from a network volume, a different disk or another operating system. See Change your Mac startup disk.
To change these settings, choose Apple menu 
in the sidebar, then click Startup Disk on the right. (You may need to scroll down.)
Open Startup Disk settings for me
Important: If you have a Mac with an Apple T2 Security Chip, added security features may need to be set in order to change the startup disk. See What is the Startup Security Utility? If you have a Mac with Apple silicon, see Change the security policy.
Option | Description | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Startup Disks | Shows the disks you can use to start your Mac. Click to select the startup disk you want to use. | ||||||||||
Restart | Restart your Mac using the selected startup disk. | ||||||||||
Restart in Target Disk Mode (Mac with Intel chip only) | If you have two Mac computers with USB, USB-C or Thunderbolt ports, you can connect them so that one of them appears as an external hard disk on the other. This is called target disk mode. See Transfer files between two Mac computers using target disk mode. If you have a Mac with Apple silicon, see Transfer files between a Mac with Apple silicon and another Mac. | ||||||||||
WARNING: When selecting a network startup volume, make sure you select a network startup volume and not a network install image. Selecting a network install image reinstalls your system software and may erase the contents of your disk. A standard network volume icon appears as a globe with a folder. A network install icon appears as a globe with a downward-pointing green arrow.