I am really afraid of updating to Mojave as I would more than likely lose the ability to use some apps. How do you partition the hard drive to run either one?
Mac mini, macOS 10.13
Open Disk Utility click on View in the menubar select Show All Devices.
Highlight the Disk not any of the indented Volumes, click Partition,
click on the + symbol and use the round grey handle on the outside of the circle to
resize your new partition. Give it a name make sure the format is APFS, once you are
happy with the size and name of the new partition click Apply.
FWIW, the size is arbitrary but it depends on how much free space you have available on your drive and how many apps you think you want to install in Mojave. 40GBs would be the minimum just to install Mojave. Plus, you need to allow free space for your High Sierra install. To switch between them you hold the Option key on boot or restart.
It might be simpler to install Mojave on an external drive.
noyonana wrote:
How do you partition the hard drive to run either one?
Partition a physical disk in Disk Utility on Mac - Apple Support
Like dialabrain I advocate using an external hard disk drive instead though. It's simpler, they're cheap, and when you make a final determination about Catalina you can repurpose it for Time Machine—which you ought to be using anyway.
If despite that recommendation you decide to forego the external disk option, then I suggest you do not partition the internal:
However, with APFS, you shouldn’t partition your disk in most cases. Instead, create multiple APFS volumes within a single partition. With the flexible space management provided by APFS, you can even install another version of macOS on an APFS volume.
That obviates questions regarding individual partition capacities.
Are the GBs shown the correct amount to assign? What steps should I take to switch between the High Sierra and Mojave? In advance thanks for your help - looks pretty simple.
I would like to be able to have both High Sierra and Mojave on my Mac.
