Best way to revert to Sierra from High Sierra??

[prof]

I have a client that wants to upgrade their computer to High Sierra from Sierra but they're concerned that some of their older software may not work properly. What is the best way to do the High Sierra upgrade for them and then revert to Sierra if they don't like the results??

TIA,
Prof

[Gareth]

Make a cloned backup of the Sierra drive. You're going to need to nuke and pave the High Sierra drive if you want to revert since the file system will get upgraded to APFS for High Sierra, and you'll need to revert to HFS+ for Sierra. So, if you want to go back, you'll have to erase the High Sierra drive and clone the Sierra drive back.

Note that some software with activations doesn't always take kindly to be cloned, so they may need to be re-activated afterwards.

However, unless the software is really, really old, it should be fine. I ran High Sierra for years and years and years and only recently just updated to Mojave. And the only thing that I found that didn't work was Quicken 2007's auto-backups since it didn't like APFS.

[prof]

Thanks for the reply. I'm guessing that the upgrade will be OK but trying to be on the safe side. I did find that there's a way to bypass the APFS conversion when installing High Sierra. Is it possible to do an upgrade when using the regular High Sierra installer??
The client doesn't want to do any software reinstalls which would be required if the High Sierra installer does a clean install of the OS.

[RAMd®d]

To be safer, he could install High Sierra on an external drive and boot from it, then install the apps he's concerned about.

I don't use a lot of apps, but I didn't find anything that stopped working with High Sierra.

But this is a YMMV situation.

[Gareth]

High Sierra doesn't (by default) do a clean install. It does the APFS file conversion in place.

It is possible to run High Sierra on HFS+. That's how I ran it for all the years I used it. If you want to go that route, check and make sure the instructions you're reading are "current". My understanding is that it may not work with the latest installers (which are the only ones that work anyway since Apple "messed" up all their old installers. However, it's also possible to clone a High Sierra installation back to an HFS+ drive if needed.

[hal]

Upgrading and downgrading would be an immense waste of time if some of the software isn't compatible. It might be easier to just check the installed software OS requirements one by one.

That said, it's going to be time to upgrade eventually.

[davester]

Also, as long as you're upgrading, why not skip High Sierra and go to Mojave? That'll give you a tiny bit more futureproofing and will still run 32 bit apps. The only downside that I've encountered is that Mojave will give a warning the first time you run your 32 bit app that your developer should update the app (to 64 bit). After that it's smooth sailing as far as I can tell.

[AllGold]

I would just do a clone. Revert to the clone if the update doesn't fly. But if they're already on Sierra then I think High Sierra should be fine.

davester wrote:
The only downside that I've encountered is that Mojave will give a warning the first time you run your 32 bit app that your developer should update the app (to 64 bit). After that it's smooth sailing as far as I can tell.

I think High Sierra does that too.