SD! and Catalina vs. Ventura

[rbpeirce]

I backup my Catalina computer to a removable drive formatted as APFS. SD! backs up Cataliina in two phases, System Files and Files. When finished Disk Utility shows them as two volumes, which is sort of weird in that SD! must create this volume on the fly. More weird is when I attach the drive to my Ventura computer. Then the Catalina backup appears as a volume with sub-volumes. I guess that is possible but I've never seen it. I tried to partition a volume into two and couldn't.

To make matters worse, a backup of Catalina to another drive shows up in Disk Utility on Ventura as a volume with 5 (!) unmounted sub-volumes. When I try to mount it it says "Invalid Disk." However, when I swap it back to the Catalina computer it mounts correctly.

To be safe I am going to backup my Catalina computer to drives I don't use on Ventura. That's wimping out but I have no idea what is going on! Does anybody have any ideas? Are Ventura and Catalina that radically different?

 

[MacInWin]

All of that is totally normal. Catalina, and more recent versions, has two Volumes in the Container on the internal drive. One is default named "Macintosh HD" and the other is default named "Macintosh HD - Data." When that internal storage is the boot system, the two Volumes are fused into one, named Macintosh HD. However, when you make a clone with SD!, the two are separate because it is NOT the boot drive, and hence, not fused. The other smaller Volumes are required for the OS to be able to boot from the backup. They are also on the internal drive, but hidden. None of the hidden will mount.

Catalina and Ventura work the same on APFS, so I'm not sure what you mean by this:

More weird is when I attach the drive to my Ventura computer. Then the Catalina backup appears as a volume with sub-volumes.

Can you post a picture of what Disk Utility shows for that drive in both Ventura and Catalina? That would help us understand what is going on better. Is that external drive used for anything other than the Catalina backup?

 

[rbpeirce]

you post a picture of what Disk Utility shows for that drive in both Ventura and Catalina? That would help us understand what is going on better. Is that external drive used for anything other than the Catalina backup?

I deleted them for safety reasons. However, Google tells me this is a volume "group" but not how it is created. I can't find that option in Disk Utility.

When I backup my Ventura HD using SD! I only get one file, I suspect Data. I've read you can't actually make a bootable backup with Ventura. Apparently you can with Catalina and that's why I got two files.

Just to be safe I'm only doing Catalina stuff on drives restricted to Catalina and the same for Ventura. This seems to work but it is going to take some time to get everything copied correctly.

 

[MacInWin]

I deleted them for safety reasons. However, Google tells me this is a volume "group" but not how it is created. I can't find that option in Disk Utility.

When I backup my Ventura HD using SD! I only get one file, I suspect Data. I've read you can't actually make a bootable backup with Ventura. Apparently you can with Catalina and that's why I got two files.

Just to be safe I'm only doing Catalina stuff on drives restricted to Catalina and the same for Ventura. This seems to work but it is going to take some time to get everything copied correctly.

Ignore what Google may have said. As i said, when you format a drive as APFS, and then install the operating system, you end up with five Volumes in the Container. Three are hidden, normally, the main drive is named with HD as the end and the Volume with your data ends in Data. If you want to read more about what is going on, go to Eclectic Light Co website and search for APFS. There are dozens of articles on what Howard Oakley has been able to find out about how APFS works with Apple Silicon.

Search Results for “apfs” – The Eclectic Light Company

Macs, painting, and more

eclecticlight.co

Then search for "Boot" at the same place and read about the boot process and what it involves with Ventura and Catalina. He even discusses booting from an external drive and what that entails.

You are correct, I think, about SD!. I have heard it doesn't make a backup of the system Volume in Ventura. I think what you have to do to get a bootable clone is to install Ventura to the backup drive first, then run SD! and clone the data to it.

Bootable backups on Apple Silicon systems really aren't necessary, unless you have a spare identical Mac around to use it on. If the internal drive fails so badly that you need to boot from an external, the system won't boot in any event because it needs to have access to that internal storage before it looks for the boot system. Therefore, an internal storage failure will essentially render the machine unbeatable. The clone will only be useful to boot another, working, Mac. That expense of having a spare Mac sitting on a shelf may be practical to a company that cannot tolerate even one hour of downtime, but for most of us, it's a bit extreme. If my MBP, for example, fails in that way, I'll have to consider getting a replacement, which will take some time to arrive and time to restore from my backups, so I don't need a bootable backup any more.

Your new approach of only using the drives for one backup is wise. As I have said before, TM now takes over the backup drive completely, including changing the format of the drive, if needed.