How to create a RAID on Mac

When you create a random array of independent disks (RAID) on your Mac computer, it can greatly increase the read and write speed of your hard disk drive. You need at least two storage drives to successfully set up the RAID. It can be two hard disk drives or two solid-state drives, both with the same amount of storage capacity.

For instance, you can choose two 1TB hard-disk drives, two 512MB solid-state drives, or so on. It is important that you match the types of drives and their capacity. That will ensure the RAID functions more efficiently. You will be connecting these storage drives together so that they’re treated as one storage drive by your computer.

The RAID level you create will determine how many storage drives that are used. If you create a RAID 5, for example, then you need three hard disk drives. If you create a RAID 6, for example, then you need four hard disk drives.

Steps for Creating a RAID

The macOS operating system comes equipped with a Disk Utility program. You can use the Disk Utility to perform all kinds of disk management activities, such as repairing disk errors, wipe disks clean, and create RAIDs for disks. So, you’ll need the Disk Utility to create a RAID set on your Mac computer.

Open the Disk Utility and perform these steps.

1) Open the Disk Utility program on your computer. You can find it by going to the label “Finder,” then User, then Applications, and then Utilities. The path may be slightly different depending on which version of Mac OS you are using.

2) The left side of the window will show a list of the disks that are connected to your computer. If you’re going to use all the disks in your new RAID creation, then select each disk in the window and format it. Go to the Erase tab to find the formatting options. It will let you wipe the disk clean.

3) Once all the disks are formatted, select a disk and then click on the RAID tab over on the right side of the window. You should see a text box labeled “RAID Set Name.” Use this box to give your RAID creation a new name.

4) Under the Format dropdown button, you’ll want to select “Mac OS Extended “Journaled).” This is the most recent RAID format that works with newer Mac computers.

5) Under that, you need to select which type of RAID that you want for your RAID set creation. You can choose between a Striped RAID set and a Mirrored RAID set. The striped RAID set is good for users who want faster write and read speeds on their computer. This RAID set splits data amongst each of the four drives, which forces them all to read and write data simultaneously. If you choose the mirrored RAID set type, all of the data gets written to each disk rather than split up amongst them. This is great if you want to back up all your data in case one of your disks gets damaged or has a malfunction.

6) Finally, drag the disks from the left side of the window to the right side. This tells the utility that you want to use these disks in the RAID set. It’ll tell you the total capacity of all the drives together. Now just click the “Create” button to create the new RAID set.

7) You should see the new RAID set listed underneath the other disks on the left side of the window. You can now store files in the RAID set as you please.