Dan Pražák New macOS 10.15 Catalina released for regular users and brings with it a number of new features. But if for whatever reason you want to try out the new system safely first, there is a fairly simple way to install it yourself and keep macOS Mojave. At the same time, you will achieve a clean installation of the system, thus avoiding the possible occurrence of errors.
Just create a separate APFS volume for the new system. The main advantage is that the space for the new volume does not need to be reserved in advance, because the size of the volume is variably adapted to the needs of the given system and the storage space is shared between the two APFS volumes. Anyway, for the new system you need to have at least 10 GB of free space on the disk, otherwise the installation would not be possible.
How to create a new APFS volume
- On your Mac, open Disk Utility (in Applications –> Utilities).
- In the right sidebar label the internal disk.
- At the top right, click on + and enter any volume name (such as Catalina). Leave APFS as the format.
- Click on Add and when the volume is created, click on Done.
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How to install macOS Catalina on a separate volume
Once you have the new volume created, just go to System preference -> Software update and download macOS Catalina. After downloading the file, the installation wizard will start automatically. Then proceed as follows:
- On the home screen, select Continue and in the next step agree to the terms.
- Then choose View all discs… and select newly created volume (named by us as Catalina).
- Click on Install and then enter the administrator account password.
- The installation will be prepared. Once complete, select Restart, which will start the installation of the new system on a separate volume.
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The Mac will restart several times during the installation process. The whole process takes several tens of minutes. You will then be prompted to complete the installation, where you will log in to your iCloud account and set some preferences according to your preferences.
How to switch between systems
After installing macOS Catalina, you can switch between the two systems. Go to System preference -> Startup disk, click on the bottom right lock icon and enter administrator password. Then select the desired system and click on Restart. Similarly, you can also switch between systems when starting up your Mac by holding down a key Alt and then select the system you want to boot.
Hello, how do I uninstall the old OS? And will it not matter that I will have Catalina as the only OS on a special disk? Thank you
... what Pavel is asking (Hello, and then how do I uninstall the old OS? And will it be okay to have Catalina as the only OS on a special disk? Thank you) I'm also interested, because after 5 years I would be able to install the system cleanly, so it is then necessary to transfer data and applications to the new volume and then cancel the old one, or not to deal with it, that the OS team will deal with it on its own and leave it all as it is?
Hello, how do I uninstall the new or old OS? Thank you very much for the advice!
Dear Mr. Editor,
I think it would be polite when you write such an article to answer the questions that arise from the article. You already have several questions about the same thing here and you leave it unanswered. If you are providing "advice" to a tip such as your article, it would be appropriate to write something with the original volume as well.
The original volume can be deleted after you press the ALT key after startup and hold it until a menu of disks from which you want to start the MAC appears. Select e.g. TimeMachine (you must have a disk with TM/ or you can connect a USB key with OSX installation, etc.) and after the menu appears, select a disk utility with which you can delete the original disk. You then select Catalina as the startup disk and reboot. That should be all done