Starting a Client Mac from NetBoot or NetInstall
Using NetBoot to start a Mac is sometimes called diskless booting because the client Mac doesn’t actually need a hard disk.
You can start a client Mac from a NetBoot or NetInstall image by holding down the N key while restarting the client Mac. This action forces the Mac to look for a server with the NetBoot/NetInstall image. Release the N key when a globe icon appears onscreen. If you have a NetInstall or NetRestore image, the Mac starts from the image on the server and begins the installation process.
If you want the Mac to always boot in diskless mode from NetBoot, select it as the default startup drive in System Preferences as follows:
1. Boot the Mac from the NetBoot image by restarting while holding down the N key.
2. Open System Preferences from the Apple menu and click the Startup Disk icon.
3. Select the network volume that appears in the list.
4. Click the Restart button.
You need to have file service turned on, because NetBoot uses file sharing to set up share points that the client Macs can boot from.