Installing macOS Catalina on OS X Extended Journaled Filesystem drive

Ok

i find solution for my scenario : from Mojave to Catalina.

steps

• restart your mac in recovery mode (option + cmd + R)
• choose disk utility
• unmount your drive
• convert drive to apfs
• esc from utility disc and install Catalina

bye

vincenzo

Clone to an external APFS formatted disk (you can partition it if you like *). Then, as a bonus, you can continue to use it as a bootable Carbon Copy Cloner backup of your internal disk. Another alternative is to use the external disk as a TimeMacine backup disk later after you get this thing done.

* I'd recommend getting a SSD disk the same size or maybe somewhat bigger than your internal drive so there is some extra space for Carbon Copy Cloner's "safety net" or another partition (When the SafetyNet is on, CCC places the older versions of modified files, and files that have been deleted from the source since a previous backup, into the _CCC SafetyNet folder at the root of the destination). Personally I don't use safety net but I have a 2nd backup disk that I update only monthly.

No, because if you add a partition, you won't be able to remove the older partition and reclaim its space.

Note that if you add a partition, you won't be able to reacquire the space used by the first partition.

No, because only the last made partition (the newest one) can be recovered. Do what Matti suggested.

No isn't possible because when start with restore from time Machine he reformat disk again in MAC OS Extended.

Use Carbon Copy Cloner to clone to APFS-formatted volume, reformat internal disk as APFS, and clone back to it. It might be a good idea to have a 2nd backup in case something goes wrong (it won't, but just in case some drive decides to break just then...).

Same issue here. Apple Support told me yesterday by phone they are hoping for a fix to this problem, but told me the following would work. I use Time Capsule to back up my Macbook Pro.

• Make sure I've got a fresh Time Machine backup
• Restart the Mac in Recovery Mode (hold down Command-R during until Apple logo appears)
• choose Disk Utility and reformat the hard dis (1TB SSD in my case) as APFS. This will wipe the disk clean.
• Restart the Mac again in Recovery Mode (Command-R)
• Choose restore from Time Capsule/Time Machine
• Wait 15-24 hours for Time Machine restore to complete.

Huge waste of time, and you'd better have a good, reliable backup!

Apple Support suggested I wait a few days to see if Apple comes up with an easier solution. Seems worth waiting...