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GSPice

macrumors 68000
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Nov 24, 2008
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So I've read a couple conflicting articles on how Time Machine backups are affected by Sierra's new "Store in iCloud" feature - in summary:

Pre-Sierra, a user could have potentially 3 copies of a file: locally, in iCloud, and via Time Machine backup.
With Sierra's "Store in iCloud" enabled, some explain that if a file is in the Desktop or Documents folder (now synced to iCloud), potentially only one copy that will exist (iCloud), as it may eventually be removed from local storage, and as a result, will no longer be backed up by Time Machine. This is not to mention the difference between iCloud file storage and Time Machine versioning storage. Others explain that Time Machine will still back up these "iCloud-only" files, by Sierra downloading them as necessary for this purpose.

I've gotten no positive confirmation on any forums or Apple support site on what's actually going on, so I'll throw this idea out there and see if anything sticks:

Sierra Time Machine Paradigm (assuming an "always-connected" TM solution, or Time Capsule)
1. Mac is updated to Sierra (all local files still local)
2. Time Machine backs up all local files as usual
3. Sierra "optimizes" old files, removing them from local storage
3.a. At this point, Time Machine does not need to back up these old files again, as they are unchanged from (2).
4. User makes changes to "optimized" file on Mac: Sierra downloads file for editing; is now in iCloud AND local
4.a. Time Machine backs up this new version of the file, as it is now local
4.b. Time Machine has now backed up the two versions of this file (versions in step 2 and step 4)

So with this explanation, even with "Store in iCloud" enabled, a user still has at least 2 copies of the file (TM and iCloud), even if the file becomes "old" and "optimized" again.

So my questions are:
a) Can anyone confirm this behavior, and
b) What if step 4's file change was done by an iOS device, instead of the Mac? Would the file then become "recent" to all iCloud devices and thus be downloaded locally to each device (to then be backed up by TM)?

Sorry this is so wordy, but *every* attempt by tech sources to explain how this works has been very wordy, and unclear (which points to Apple's inability to keep a "simple" feature "simple.)
 
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Make a few files, put them in interesting locations, and watch what happens as you make changes to them over the course of a few days. As control, make some files, put them in the same interesting locations and see what happens to them vs your regularly modded files. Check inside Time Machine for the files too.

That should tell you what you want to know.
I'm not sure why Apple didn't come out with at least a tech note explaining how this all works.
Maybe they did, and I just haven't found it yet.
 
Put me on the list of people interested in the question but unable to answer it.

I wouldn't be surprised if a future version of Time Machine allowed for backups to iCloud instead of to an external HDD. But trying to figure out the intersection between iCloud sync, Optimize Storage, Time Machine, Fille versions, and APFS is making my head hurt.

The ideal behaviour for me would be that all my files are in iCloud, there is a local copy of the most recent versions of the most used files, and an app like Time Machine allows me to access the older versions transparently (and they happen to be stored on iCloud). I'd have to assume they're building towards some flavour of this. But not sure how all the pieces of enabling technology fit together.
 
Let me share an experience I just had with this.

I had a Powerpoint file in my Documents folder, which is stored in iCloud. The file was local, and I needed to recover an earlier version of the file (Saved instead of Save As, doh!). I opened Time Machine, and was able to retrieve the file - but it kept the iCloud Version and created a duplicate. The typical TM behavior is to overwrite, but instead, it created a copy.

Hopefully someone is able to shed some light on this.
 
Let me share an experience I just had with this.

I had a Powerpoint file in my Documents folder, which is stored in iCloud. The file was local, and I needed to recover an earlier version of the file (Saved instead of Save As, doh!). I opened Time Machine, and was able to retrieve the file - but it kept the iCloud Version and created a duplicate. The typical TM behavior is to overwrite, but instead, it created a copy.

Hopefully someone is able to shed some light on this.

Chuck- From personal experience you somehow missed (or didn't get) a prompt to keep the original, both or only the file you were retrieving from the TM snapshot. I've gotten that prompt every time I've tested recovering an older version of a file from a TM snapshot.

regards,

BD
 
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So I've read a couple conflicting articles on how Time Machine backups are affected by Sierra's new "Store in iCloud" feature...

A *much* better question... why in the WORLD are you considering trusting your data to Apple's ability to provide cloud storage? They have not demonstrated such ability so far.
 
A *much* better question... why in the WORLD are you considering trusting your data to Apple's ability to provide cloud storage? They have not demonstrated such ability so far.

Odd, I've been using TM and iCloud from day one. Rock solid. Anyway, back to the OP's question... ;)
 
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I've never experienced a data loss inside iCloud either. Regardless, a copy of your data is stored locally on your hard drive if you use the Desktop and Documents Folder storage feature in iCloud so Time Machine can recover anything stored in those folders from snapshots just as it always has.
 
I've been using TM and iCloud from day one. Rock solid.
My TM rock has sprung holes and sunk without a trace on at least 3 separate occasions. I like it for hourly BU of docs I'm working with, but use other methods for trustworthy long term redundancy.
 
Odd, I've been using TM and iCloud from day one. Rock solid. Anyway, back to the OP's question... ;)

Time Machine is reliable, for what it is. iCloud, Apple has not demonstrated that they have what it takes to maintain a cloud-based storage solution. The idea that important files are ONLY in the cloud? That the OS will arbitrarily decide what should be placed there and what should be local? No, not with anything *I* care about.
 
Regardless, a copy of your data is stored locally on your hard drive if you use the Desktop and Documents Folder storage feature in iCloud so Time Machine can recover anything stored in those folders from snapshots just as it always has.

So what happens when Sierra decides to remove a file from local storage?

Are you saying that by the time that happens Time Machine would have already created a snapshot of the file while it was local?
 
Correct. If TM has created a snapshot of a file which was later removed from the local drive for any reason that file is retrievable from a TM snapshot...no difference in the way it worked before.
 
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Correct. If TM has created a snapshot of a file which was later removed from the local drive for any reason that file is retrievable from a TM snapshot...no difference in the way it worked before.
I see. And what if an iCloud-only file is edited (thus downloaded) on an iOS device. Is the new (edited) version of the file also downloaded on the Mac to be made available for a new Time Machine snapshot?
 
I see. And what if an iCloud-only file is edited (thus downloaded) on an iOS device. Is the new (edited) version of the file also downloaded on the Mac to be made available for a new Time Machine snapshot?

Yes, the file generated from an iOS device downloads to your iMac during the next synchronization.

Here's a link to some early tests I've conducted with Sierra iCloud Desktop and Documents activated if you're interested:

https://discussions.apple.com/thread/7710466?start=15&tstart=0
 
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Not that I'm aware of (other than personal testing linked above)
Excellent - thanks!

Next thing is to confirm your suspicion that iCloud-only files updated by another device are re-downloaded by any other Macs to allow for Time Machine to create a snapshot with the new version of the file.
 
I like the option to optimise storage, but only because I have an iMac and a MacBook: my iMac is configured with optimisation turned off so I always have a local copy and my MacBook has it turned on so I don't fill the limited storage up with stuff I don't need.

My MacBook time machine backup doesn't contain stuff I have never downloaded or accessed on my MacBook from what I can tell from the size of it

I also sync my iCloud documents back to a synology NAS on my iMac using Synology CloudSync and that NAS is backed up using CrashPlan: I am happy to use iCloud storage as a convenience but would never trust it (or any single provider) with the only copy of my data!
 
Excellent - thanks!

Next thing is to confirm your suspicion that iCloud-only files updated by another device are re-downloaded by any other Macs to allow for Time Machine to create a snapshot with the new version of the file.

From my limited testing with three iMacs all using this feature syncing to my one iCloud account shows any document saved to the Desktop or Documents folder quickly syncs and downloads a mirror copy to each of my three iMacs as soon as they are all online. There's no interaction required. Since all three iMacs use TM, I actually have three backup images albeit on one shared Time Capsule.

Between those three TM backups on my TC and manual backups of any critical data that changes on a separate external drive as well as another offsite backup I feel I'm pretty well covered. So much that I'll probably do away with that last offsite backup perhaps a year from now when I feel comfortable we've really stress tested the new system.

The issue I referred to in my ASC discussion link was more a question of what happens when a user accidentally leaves an iCloud Desktop or Document stored file open on his iOS device while simultaneously performing a file or macOS image rollback from Time Machine on his iMac...what happens to that file when it's in an open state on an iOS device during the macOS roll back or modified and saved from iOS a few minutes before the macOS roll back completes?

One of our other ASC members is testing this scenario and will report results on that same thread I hope. I suspect file time stamps will rule and the user will be prompted on which copy to keep but that is speculation again on my part. Regardless, I'm very impressed with what Apple has created with this feature. I haven't tripped it up yet;-)
 
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From my limited testing with three iMacs all using this feature syncing to my one iCloud account shows any document saved to the Desktop or Documents folder quickly syncs and downloads a mirror copy to each of my three iMacs as soon as they are all online. There's no interaction required. Since all three iMacs use TM, I actually have three backup images albeit on one shared Time Capsule.

Between those three TM backups on my TC and manual backups of any critical data that changes on a separate external drive as well as another offsite backup I feel I'm pretty well covered. So much that I'll probably do away with that last offsite backup perhaps a year from now when feel comfortable we've really stress tested the new system.

The issue I referred to in my ASC discussion link was more a question of what happens when a user accidentally leaves an iCloud Desktop or Document stored file open on his iOS device while simultaneously performing a file or macOS image rollback from Time Machine on his iMac...what happens to that file?

One of our other ASC members is testing this scenario and will report results on that same thread I hope. I suspect file time stamps will rule and the user will be prompted on which copy to keep but that is speculation again on my part. Regardless, I'm very impressed with what Apple has created with this feature. I haven't tripped it up yet;-)

I've come across a similar situation - the file wasn't accidentally left open, but between network signal on my iOS device, and the Mac not having enough time to download the iOS-edited version of the file, the Mac prompted me to select one (or both) versions of the file: the iOS edited one, and the Mac edited one.

The issue I'm thinking of is when an iCloud-only file (a Sierra-optimized file removed from any local storage on any Mac) is edited by an iOS device. I'd like some evidence (even anecdotal) that the file is downloaded by all Macs to be available for local backup. (I'm not talking about existing local files syncing via iCloud, but files that no longer exist locally)
 
I've come across a similar situation - the file wasn't accidentally left open, but between network signal on my iOS device, and the Mac not having enough time to download the iOS-edited version of the file, the Mac prompted me to select one (or both) versions of the file: the iOS edited one, and the Mac edited one.

The issue I'm thinking of is when an iCloud-only file (a Sierra-optimized file removed from any local storage on any Mac) is edited by an iOS device. I'd like some evidence (even anecdotal) that the file is downloaded by all Macs to be available for local backup. (I'm not talking about existing local files syncing via iCloud, but files that no longer exist locally)

Good question...and one I really can't answer. I would *hope* as long as it's been saved to the Desktop or Document's folder it would be eligible for restore by a TM roll back on your iMac as that would be an expected scenario at some point with Optimization enabled as the system chose to move it, not you.
 
Good question...and one I really can't answer. I would *hope* as long as it's been saved to the Desktop or Document's folder it would be eligible for restore by a TM roll back on your iMac as that would be an expected scenario at some point with Optimization enabled as the system chose to move it, not you.
I agree - I know that TM could roll back to a file that was once local; but maybe an iCloud-only file being edited by iOS would trigger the file to be re-categorized as no longer "old" (no longer qualified for "optimization"), and be redownloaded.
 
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