Can Carbon Copy Clone keep a current backup, except with a previous MacOS?

[Howard Brazee]

Can Carbon Copy Clone keep a current backup, except with a previous MacOS?

I've had programs break with MacOS upgrades. I'd love to be able to just boot to my external drive and have everything the same, except for the MacOS upgrade that I installed.

 

[TonyAguila]

Can Carbon Copy Clone keep a current backup, except with a previous MacOS?

I've had programs break with MacOS upgrades. I'd love to be able to just boot to my external drive and have everything the same, except for the MacOS upgrade that I installed.

As far as I know, to this day, Carbon Copy Cloner will not create bootable copies of macOS ever since Apple introduced the dual-partition scheme (system/data) starting from macOS 10.15 Catalina. I think SuperDuper is able to create bootable copies but, personally, I’m partial to CCC. My strategy had always been to create CCC clones of system volumes, and if and when I need to create a bootable volume, I would start with an empty volume, install the version of macOS that I want, and then when asked for the migration source, I would point it to the CCC clone.

One thing to keep in mind is that the oldest version of macOS your Mac is capable of running is the version that it originally came with. On my 2018 Mac mini, I was able to run Mojave because that’s what it came with. But with my Mac Studio, I have no choice aside from macOS Monterey. It came with macOS 12.3, so I doubt that it will even run version 12.2. But I just updated to 12.3.1 so I know I can at least revert to 12.3.

In short, if your Mac came with an older version of macOS that your are running at present, you should be able to create a secondary system with the previous version of what you now have. You might want to give SuperDuper a try, but for now, I’m staying with CCC in spite of the additional hassle.

 

[Howard Brazee]

I have an M1 iMac with a 2TB drive. I bought a 2TB drive. If I am not mistaken, I'm thinking that my solution should be to create a boot drive on my hard drive, then clone my main drive to this. Or I could just run SuperDuper to do that one step. I tried last month to create a bootable drive with an earlier version of MacOS (I also have a 1TB drive that I tried to do that with), but I failed.

Then I would either put aside CCC or SD or set them up to migrate limited folders.

Someday in the future after I install the next named version of MacOS on my main drive, and have tested out everything, I would repeat this procedure, overwriting my disaster disk.

Is that how you see it?

 

[TonyAguila]

I have an M1 iMac with a 2TB drive. I bought a 2TB drive. If I am not mistaken, I'm thinking that my solution should be to create a boot drive on my hard drive, then clone my main drive to this. Or I could just run SuperDuper to do that one step. I tried last month to create a bootable drive with an earlier version of MacOS (I also have a 1TB drive that I tried to do that with), but I failed.

Then I would either put aside CCC or SD or set them up to migrate limited folders.

Someday in the future after I install the next named version of MacOS on my main drive, and have tested out everything, I would repeat this procedure, overwriting my disaster disk.

Is that how you see it?

I really wanted to get a four-terabyte SSD in my Mac Studio but I don’t give in to highway robbers. Another $600 for an additional 2TB? I don’t think so. Anyway, I already have 8TB of external SSD storage and 32TB of hard drive space connected to the Mac.

First you have to understand the difference between Time Machine backups and clone backups. They complement each other and are not mutually exclusive. Time Machine, in my opinion, is more important. Clones are basically mirror image copies of your drive. Even if CCC supports snapshots, it can get messy and I rely on Time Machine in restoring particular files or folders that I need earlier versions of, or current copies if the ones I had got messed up or deleted. But for purposes of restoring whole drives or files/folders quickly, CCC or SD are better. For Time Machine to be truly reliable, I maintain at least two drives to alternate in backing up my data.

As I said, I prefer CCC over SuperDuper because I don’t need bootable clones, and I have simply gotten used to CCC’s interface. So whenever I need to fully restore a system drive, I first totally erase that drive, reinstall macOS, then migrate my data from the clone. Why copy back the system partition when the reason for restoring that disk is probably because of a corrupted system. A simple reinstall is usually the first option to take—quick and easy. But sometimes a full erase and restore is needed. What’s better than a fresh system partition before restoring your data?

If I were setting up your system, I would want an external Thunderbolt (-3 at least, -4 much better but harder to find) multiple drive enclosure. I have a couple of 4-bay enclosures. I think you will be okay with one. Two hard drives, at least 4 TB each for Time Machine, and two SSDs, one for cloning, the other for you “other” system. You can even get away with hard drives for cloning, but they can be slow. I clone my systems three times a day and a slow drive can be intolerable.

Why Thunderbolt? For the SSDs. It’s vital that your external SSD support TRIM, or the health of your SSDs will suffer. The system needs to see those external SSDs as SATA devices, otherwise TRIM cannot be enabled and your SSD will degrade over time. And every time you reset your parameter RAM (PRAM), trim will be disabled and you will need to issue a command to turn it back on.

Wow! I have gone on and on. Anyway, you said you wanted to create a bootable drive with the older version of macOS installed. Keep in mind that your M1 iMac will support the version that that it came with and later. It will not run even older versions. Your Mac came with macOS 11.3 (20E232). If you are running the latest version of Monterey now (12.3.1) you can install anything between this and 11.3.

As long as you have the macOS installer file for what you want, you can easily make a fresh installation on your external drive, and then use your clone to migrate your data to it. You can choose the data that you want to migrate. It doesn’t have to be everything.

By the way, rumor has it that the next major macOS update will be “Mammoth.” We shall find out at the upcoming WWDC.

 

[Howard Brazee]

Absolutely, Time Machine is far more useful. I will be much more likely to need to get the version of a document from last fall than I will need to boot up with last month's MacOS. Which doesn't mean that I haven't needed to boot up with last month's MacOS.

 

[Howard Brazee]

I keep fantasizing about using Thunderbolt, but deciding that I just can't afford it.

 

[TonyAguila]

Absolutely, Time Machine is far more useful. I will be much more likely to need to get the version of a document from last fall than I will need to boot up with last month's MacOS. Which doesn't mean that I haven't needed to boot up with last month's MacOS.

In this case (needing an older version of a document) I don’t see much need for a secondary boot drive with an older system since your iMac is fairly new. I would not expect incompatibilities with more recent apps running in Monterey vs. in Big Sur. All you will need are a pair of Time Machine drives, and they don’t have to be connected by Thunderbolt.

Since I don’t believe your 2-TB internal drive will become even 50% full in the near future, just get a couple of USB 2.5" hard drives for Time Machine. For now you don’t have to worry about needing to run Big Sur. I had a need for it with my 2018 Mac mini because I even had 32-bit apps that required Mojave.

2-TB USB drives are now very affordable. Just make sure you format them as APFS for TM, and, of course, encrypted. You can forget about the external Thunderbolt enclosures.

 

[Howard Brazee]

My Time Machine is 4TB spinning disk, with a couple of USB A ports in front (which are useful). I don't need speed for Time Machine, I need space. My goal with my SSD is to be able to boot to a version of MacOS that didn't break the program that I need.

 

[TonyAguila]

My Time Machine is 4TB spinning disk, with a couple of USB A ports in front (which are useful). I don't need speed for Time Machine, I need space. My goal with my SSD is to be able to boot to a version of MacOS that didn't break the program that I need.

All you need to do is to secure a copy of the installer file for the previous version of macOS that you wish to install on the external SSD. You then have to create an installer drive (USB stick, SD card, etc.) for that macOS installer. Once you have that installer drive, you then boot from it (selecting it as startup drive from Control when you boot up while holding down the power switch. Select the target drive and proceed with the installation.

Afterwards, when you are booted from the new (actually, older) system, you can proceed with the setup and, if you wish, migrate data from your internal drive or Time Machine backup.