Choosing the right startup disk for your Mac can be crucial, especially if you have multiple operating systems or need to troubleshoot your computer. Here’s a step-by-step guide on how to pick a startup disk for your Mac at boot time.
Setting a Default Startup Disk
To set a default startup disk, follow these steps:
- Open System Settings: Click the Apple symbol in the menu bar and select System Settings.
- Navigate to Startup Disk: Click General in the sidebar and then select Startup Disk on the right.
- Select the Disk: Click the icon of the disk you want to use as the default startup disk. You may need to scroll down to find it.
- Confirm the Change: Enter your admin password or use Touch ID if prompted. Then, click Restart to apply the changes.
Temporarily Changing the Startup Disk
If you need to temporarily change the startup disk, you can use the Startup Manager:
For Macs with Apple Silicon
- Shut Down Your Mac: Click the Apple symbol in the menu bar and select Shut Down…, then confirm in the dialog prompt.
- Access Startup Options: Press and hold the power button until "Loading startup options" appears on the screen. For Mac mini, wait for the system indicator light to turn amber.
- Select the Startup Disk: When you see the available startup volumes, select the one you want and click the Continue button.
For Intel-Based Macs
- Shut Down Your Mac: Click the Apple symbol in the menu bar and select Shut Down…, then confirm at the prompt.
- Access Startup Options: Press and hold the Option key as you press the power button to start up your Mac.
- Select the Startup Disk: When you see the available startup disks, select the one you want and click the Up arrow.
Important Considerations
Network Startup Volumes
When selecting a network startup volume, ensure you choose a standard network volume icon (a globe with a folder) and not a network install image (a globe with a downward-pointing green arrow). Selecting a network install image can trigger a reinstall of macOS and may erase your data.
External Drives and Volumes
If you don’t see the volume you want to start from, make sure it’s connected and turned on. Also, ensure that the volume contains a valid operating system. Volumes without an operating system will not be listed in Startup Disk or Startup Manager.
Secure Boot T2 Chip
For Macs with the Secure Boot T2 Chip, you may need to set additional security features via the Startup Security Utility to change the startup disk. Consult Apple’s user guide for more information.
Troubleshooting Tips
Missing Volumes
If a volume is not listed, check that it is properly connected and contains a valid operating system. If the volume is not recognized, it might need repair. You can start your computer from OS X Recovery and use Disk Utility to repair the volume or reinstall the operating system.
Starting from Recovery System
To start your Mac from the Recovery System, hold down the Command and R keys on your keyboard until you see the Apple logo appear onscreen. This can be useful for repairing or reinstalling macOS.
Forcing the Boot Disk Selection Menu to Appear Every Time
If you need the boot disk selection menu to appear every time you start your Mac, you can use a terminal command. This is particularly useful if you frequently switch between different operating systems:
- Open Terminal: You can find Terminal in the Applications/Utilities folder or use Spotlight to search for it.
- Enter the Command: Use the appropriate terminal command to set your Mac to always prompt for the boot device on startup. This command can be found in detailed guides on forcing the boot disk selection menu to appear.
By following these steps, you can easily manage and select the startup disk for your Mac, ensuring you boot into the right operating system every time.