- Access Disk Utility via /Applications/Utilities. Make sure that the drive / drives are connected to your computer and turned on.
- Once Disk Utility is open, click on one of the drives that you want to create the RAID 1.
- Click on the RAID tab.
- Enter a name under RAID Set Name to name the drive. This will be the name of the drive that will appear when mounted in Finder.
- Make sure that the Volume Format says Mac OS Extended (Journaled).
- In RAID Type, click on Mirrored RAID Set.
- Drag the two drives that you want to create a Mirrored RAID with into the white box.
- Once both drives are in the white box, click on Create, then Create again on the Warning Message to start building the Mirrored RAID Set.
- Once the process has completed, the drive will mount in Finder.