macos as vm guest

[Michael]

> On Jun 25, 2020, at 20:50, Ryan Schmidt wrote:
> 
> If you meant that older systems can't read APFS volumes, that's true. Sierra and later can read APFS, High Sierra and later converts your boot volume to APFS if it's an SSD, Mojave and later converts your boot volume to APFS no matter what type of disk it is. El Capitan and earlier can't read APFS. If you have data you want to share with El Capitan and older, use an HFS+ disk.
> 
> Last time we got a new filesystem it was similar. Mac OS 8.1 introduced HFS+. Mac OS 8.0 and earlier could not read it. This wasn't a big problem. You could still keep any data you wanted to share with older systems on an HFS disk.

I hate names instead of numbers. It's easy to order numbered versions.

Yes, there's one that will force your boot drive to APFS. So if you need to use older systems (I have 32 bit programs that have no 64 bit replacement. I use Jack Router when streaming and recording.), that means that at least a significant portion of your system and home directory/files will be forced into a drive that cannot be shared (and it seems that the newer the system, the tighter the sandbox/the less you can put outside of /Users/<username> or on a second partition.)

>> Huh? On my 2012 MacBook Pro that I'm using for testing at the moment, I had no problem installing Catalina on an APFS volume, while also having Mojave and High Sierra installed on separate APFS volumes on the same partition, and having Lion and Sierra installed on separate HFS+ partitions, all on the internal disk. 

Now, this is a surprise to me. I thought that the newest systems forced the boot disk to be reformatted. I did not know that it was just a partition reformat.