After upgrading Mojave to Catalina I discovered my Macintosh HD was split into 2 partitions:
I tried searching for some info on the web and didn't find anything useful. Some posts on Reddit about the Beta version of Catalina. But I got the upgrade from the official release.
So, for now, I decided to return to Mojave and to search for more info about this case. Any assist here?
iMac Line (2012 and Later)
Same thread just select All Replies, page 2. But to help now, I copied and pasted the whole reply. Print the instructions and take your time:
"Last week I upgraded to Catalina and because of Catalina problems, I restored Mojave 10.14.6 successfuly from my Time Machine backup. During the process, I too wound up with the " Mac HD - Data" in Disk Utility and my used space more than doubled. It annoyed me that Catalina could force someone to buy larger external drives for backups or worse, have to buy a new computer. I spoke to a Senior Tech at Apple this AM and my disk is back to normal. Here are the steps involved - BE CAREFUL. If unsure, leave well enough alone.
1) Back up computer (!) even though it will take a long time
2) Shut Down Mac (not restart)
3) Start Mac - immediately hold down the CMD-R keys
4) When the Apple logo appears and you see the progress bar, release the keys
5) You will see eventually the MacOS Utilities screen
6) If you cannot move the arrow, use a USB WIRED Mouse (a real possibility)
7) Select Disk Utility and then Continue
8) Select "Macintosh HD - Data" DO NOT select ERASE. Please - be careful!
9) Upper menu bar of your Mac - click Edit
10) Select "APFS Volume Macintosh HD - Data" (careful - make sure of what you select) & Click 'Delete'
11) When all finished, go to upper menu bar of your Mac and select Restart
12) After you have restarted, check Disk Utility to make sure Mac HD-Data is really gone
What caused an additional mess for me was doing the Security Update 2019-002. Apple is working on a fix to prevent the Mac from freezing when installing this Security Update as other Mac users have the same problem.
Again CAUTION! Do NOT delete "Macintosh HD". Make sure you select "Macintosh HD - Data". If feeling queasy about any of this, do NOT do it. After I had performed this process, I asked the tech to repeat everything to me and I wrote it down and reconfirmed. BTW, my disk is normal now, Mojave works great. I do not need to buy larger capacity hard drives for backups.
Good luck!"
This happened to me. What happens if I restore Mojave will the drive become one again?
After reinstalling Mojave under the supervision of an AppleCare support person, I ended up with two partitions and lack of disc space.
Go to my response (Snowmill) on page 2 for step by step instructions. Follow them carefully!
(BTW for some reason I have 2 sign-ins - sometimes under 'ecotwist' or 'Snowmill' - still me)
Sorry how do I find you? Please can you send me a link? thanks
Thank you. I had a SuperDuper backup on an external drive and have restored Mojave 10.14.4. This has also restored the empty space on my drive, which was the point, really. I am even nervous about updating to 10.14.6.
Another thing I should have checked was app compatibility. It seems that Photoshop and Lightroom have issues with Catalina. See here: https://petapixel.com/2019/10/08/dont-update-to-macos-catalina-yet-if-you-use-photoshop-or-lightroom/
I can verify Carbon Copy Cloner works just fine. It clones both partitions
and, most importantly, boots just fine.
If you are cloning to a previous macOS clone, CCC will automatically take care
of all necessary changes to make the destination bootable. That is what I did
once I was satisfied with how Catalina was working for me and the results
are just as I would expect from CCC.
Note, I have no ties to CCC other than being a user of it since it first became
available way back when and I have never been disappointed.
Thank you for your reply.
Another question, should I configure Time Machine backups in a new way then? Or should I just leave it as is?
The latest version of Carbon Copy Cloner handles this OK too.
Guys, I selected the Machintosh HD - Data drive and Disk Utility cloned both exactly as the internals appear. Drive boots perfectly. Thanks!
Hullo Opposite Days.
I succesfuly used SuperDuper. I then reversed the process as Adobe are advising against upgrading because of a conflict with Photoshop. Hope that's of use.
Macintosh HD - Data: what is that?
