how to partition external hard drive mac high sierra

Since adding a more spacious disk drive is a common way to upgrade for any Mac user, let’s try to handle it: Of course, the data placed on the volume “Test-Resizing” remains untouched.

Now the source partition size became lower and we got a new partition “Second test partition”.

So, you will shrink the existing partition and then add the second one. You can simply add additional partitions by pressing the plus button and then using section control (2) to adjust its size.

Press the Partition button on the top and a new window with a partitions allocation pie chart will appear.

On the picture below you can see our test configuration - external USB drive with a single partition “Test-Resizing”.

Open Disk Utility by typing the first part of its title in Spotlight search:.

So, let’s check how to shrink a partition using Disk Utility: You can shrink partition size with no data loss if there is unused space in its volume (remember, volume is a layer of file systems above a partition). It is a common partition table for the latest Macs, but check it anyway.

You can avoid data loss while resizing the partition only for GUID-partitioned drives.

If there is something in between - you need to remove it.

You can only extend the partition to the free space right after the current partition.

So, if you built a Fusion Drive in macOS Yosemite - don’t use OS X Lion or other older versions.

If using an Apple Fusion Drive (technology that represents separate HDD and SSD drives like one logic device), never use a Disk Utility older than one used for the creation of Fusion Drive.

In this example we will use macOS High Sierra.ĭisk Utility is quite a simple tool to resize partition in Mac, but there are a few recommendations that can save your time:

Its GUI was seriously redesigned the release of “El Capitan ”, so you may notice some interface differences if running an older Mac.

You can perform any disk-related operations in macOS using the built-in Disk Utility.

How to partition external hard drive mac high sierra