Safe to test Yosemite on secondary hard drive?

[CaptSaltyJack]

I'm currently running Mavericks on what we'll call Drive A. Let's say I wanted to test-drive Yosemite to make sure all my software works okay. If I clone Drive A to an empty Drive B to back it up, and install Yosemite on Drive A, will iCloud do any upgrades that will make it inoperable in Mavericks? I know there's the new iCloud Drive. I basically don't want Apple's servers to see that I've upgraded to Yosemite and make it not possible to have a working iCloud under Mavericks should I decide to clone Drive B back to Drive A.

 

[F1Mac]

Just install Yosemite on drive B, and if you like it, upgrade drive A? Seems easier and risk free imo.

 

[CaptSaltyJack]

I'm more concerned about my iCloud not working if I switch back to Mavericks.

 

[kastorff]

I'm more concerned about my iCloud not working if I switch back to Mavericks.

One way to handle this is to create a test Apple ID for Yosemite and do a clean install on drive B. The up side is that changes you make to iCloud settings won't affect Mavericks unless you log in to Mavericks with the test ID. The "big" down side is that you won't have access to apps and services purchased with the regular Apple ID. This allows experimentation with Yosemite, but it's not a real test of your data and your everyday apps.

Doing as you describe, with a clone of drive A to drive B, using the same Apple ID, is a bit trickier. If you want current iCloud functionality preserved on Mavericks, you must not upgrade to iCloud drive within Yosemite. Also, some software updates work only with Yosemite, so if they change their data format from pre-Yosemite versions, you could be locked into Yosemite for further use of that data. I haven't seen this much, but it's something to watch for.

iCloud drive is basically an iOS 8/Yosemite service. Trying to use any combination of OS X installs and non iOS 8 devices will result in some files being invisible to some devices.

 

[CaptSaltyJack]

Thanks for that! So if I clone A to B, and boot up on B and upgrade it to Yosemite, as long as I don't manually upgrade iCloud to iCloud Drive, I should be ok?

I would do a clean install on Drive B with a test Apple ID (great idea) but I have a handful of mission critical applications I want to test out that I have installed on Drive A.

 

[fisherking]

why not just research whether your software is compatible or not? what particular apps are you concerned about? this way, you can skip a lot of time & effort exploring possibilities, and get on with work/play/etc...

 

[CaptSaltyJack]

why not just research whether your software is compatible or not? what particular apps are you concerned about? this way, you can skip a lot of time & effort exploring possibilities, and get on with work/play/etc...

Not entirely reliable. Some applications will claim compatibility but then have major bugs. The only way to really know is to actually try it.

 

[kastorff]

Thanks for that! So if I clone A to B, and boot up on B and upgrade it to Yosemite, as long as I don't manually upgrade iCloud to iCloud Drive, I should be ok?

Yes. You'll get a startup wizard the first time you boot to Yosemite which will offer to upgrade your Apple ID to iCloud Drive. Just say no.

 

[fisherking]

Not entirely reliable. Some applications will claim compatibility but then have major bugs. The only way to really know is to actually try it.

ok, but bear in mind, probably 99% of computer users don't go thru such a process....they update, and adapt. still...which apps are you concerned about? and if there's official support AND anecdotal evidence that those apps work, won't that do it?

anyway, will drop it, not my problem. just seems like a lot of work to get to a conclusion...

 

[CaptSaltyJack]

A bit of work to get to a conclusion, yes But I put in 10 hrs a day (at least) working on my Mac and if my apps fail, I am screwed. Can't talk about what apps these are, for weird reasons I can't get into. I know, it doesn't make much sense.

Thanks for the info

 

[simonsi]

A bit of work to get to a conclusion, yes But I put in 10 hrs a day (at least) working on my Mac and if my apps fail, I am screwed.

So you will have a good backup regime.

Backup, remove the machine's access to the internet and update to Yosemite (download the installer before you remove internet access).

If your Apps all work and you want to continue to use Yosemite then re-enable access to the internet and upgrade to iCloud Drive (this is the irreversible bit).

If you want to revert then do a full restore from your backup (If a TM backup simply Option-boot from the TM drive and follow the prompts).

This presumably will be the same as you needed to do when you updated to Mavericks but with the additional caution around iCloud Drive....?

 

[CaptSaltyJack]

So you will have a good backup regime.

Very much so. Offsite backup, bootable clones, the whole nine yards.

Just curious, why remove Internet access if the iCloud Drive upgrade prompts me and I can say no?

This presumably will be the same as you needed to do when you updated to Mavericks but with the additional caution around iCloud Drive....?

Very similar, yes. Except that I hadn't done a 100% clean install in years, so I installed Mavericks on a clean hard drive, and re-installed all my software on it. Once it was running the way I wanted, I then cloned that drive (a magnetic HD) to my main boot drive (SSD).

 

[simonsi]

Very much so. Offsite backup, bootable clones, the whole nine yards.

Just curious, why remove Internet access if the iCloud Drive upgrade prompts me and I can say no?

Cool

Belt-and-braces as it is irreversible and critical you can revert if you need to, you don't want any mistakes...

The only issue I have had with Yosemite involved FileVault. I had this enabled on both drives (SSD and HDD), and disabled it prior to Yosemite upgrade.

Ran Yosemite like that for a week, then as all was stable I re-enabled FV2. The encryption ran fine, then it entered "optimisation", this didn't go so well and it hung at 40%. Getting out of that involved blowing away the Core Storage Logical Groups and Volumes, then reformatting with DU and restore from TM....ho hum.

Other than that, as I don't have a Handoff-capable MBP I don't have any WiFi issues, I like the UI changes and love the iPhone and SMS continuity and it has been very stable.

 

[grahamperrin]

… concerned about my iCloud not working if I switch back to Mavericks.

Yeah, I read of someone finding trouble with iCloud Drive in that situation.

For test purposes I'd use an Apple ID with disposable data, and use a VirtualBoxVM for Yosemite.