Mac OS upgrade consequences/queries

[chagzuki]

I've been using a mac for a year or so, so I'm familiar with Mac OS to some degree, but not in depth.
I'm still running Mojave: I tried Catalina on a separate drive and decided to stick to Mojave, and I'm familiar with the installation process, creating bootable USB installation drives etc..

But just recently I started thinking it might be handy to actually access my iMac via my iPad via sidecar, for when I feel like doing some music in casual slouched-mode, away from the desk. I tried sidecar many months back for visual work, photo editing and 3d modelling, and was disappointed by the inaccuracy of using it with the apple pencil. However, for mouse-based work such as 3D modelling it was good... the latency noticeable, but not a big deal. I didn't try it with a sequencer/DAW though... I'm assuming it will work perfectly well. So I'm wondering whether to update to either Catalina or Big Sur on my main drive. That's if it's still possible to only update to Catalina now that Big Sur is out?

Having said all that, I'm anxious about anything which might screw up my system in some unforeseen way, as it's working fine right now. In the case of a problem is it possible to roll back the OS version using Time Machine, or is that a backup of user files only? I've not had a reason to use it so far.

[sprnva]

The safest option is to install Catalina to an external disk (USB/TB etc) and migrate across the data from your system drive (or from your Time Machine backup). This is how I usually test an upgrade to see if anything breaks. Then you'll be able to see what works or doesn't in Catalina. You can go back to your old system by just booting from the internal drive again. If it's all good, then you can upgrade.

Time Machine will have a full backup of your system so you could use that to go back to Mojave if you need to. But I think it's best to leave your internal disk alone if you can.

You can get Catalina via this link.

[Winstontaneous]

I just updated to Catalina on Monday on my 2012 MacBook Pro, I generally lag 18-24 months behind the latest monstrosity. Catalina's the last OSX that will will work on this model. Mostly did it to stay current with Logic Pro X...

I did several Time Machine backups the week before. In previous years' upgrades I've Carbon Copy Cloned the entire drive to an external disk, but the only time that was truly necessary was when migrating from original HD to SSD.

After a few hours of Catalina plugin update hassles (clicking "Cancel" or "Open" hundreds of times in popup windows/System Preferences "Security") I got everything sorted. Ableton Live, Bitwig, Reason, and Logic all work as expected.

[chagzuki]

Does rolling back the OS via Time Machine involve reinstalling the entire OS from the start up options/boot options, using Time Machine as a source? Or can it be done from inside the current OS?

[sprnva]

For a full system restore you'll need to boot from the recovery partition or a bootable USB.

You could try restoring your backup to an external disk and then upgrade that disk to Catalina. This way you also get to test that your backup is good.

If you install or upgrade Catalina on an external disk, I'd recommend turning off Time Machine on that drive so it doesn't do a backup until you're sure you want to keep it. Assuming you use a networked or always-connected Time Machine solution.

[waltercruz]

That's if it's still possible to only update to Catalina now that Big Sur is out?

Apple always make these things slightly harder, so do a little research before.

I'm runing Catalina for a long time, and everything works fine.

[chagzuki]

You could try restoring your backup to an external disk and then upgrade that disk to Catalina. This way you also get to test that your backup is good.

I never did go down this route, but am considering it again now (for Big Sur). My brain doesn't seem to be processing things particularly well; I'm ruminating over what could go wrong... I'm wondering about doing what sprnva suggested and thinking that it would result in audio software licenses having to all be reinstalled, assuming that machine ID is linked to the OS drive? In which case it would be a tortuous way to test compatibility.

[sprnva]

The only licence I have to reactivate after doing a new OS install and migration to a new disk is Ableton Live. The usual suspects (NI, Arturia, PA, Steinberg, IKM etc) all work fine. That said, my machine is online so it's possible some may silently reactivate in the background.

I would assume that few copy protections these days use the hard disk or include it in their checks. It's typically the network card's MAC address and maybe the system serial number.