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MacOS may lose data on APFS-formatted disk images

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181–190 of 193 posts

Re: MacOS may lose data on APFS-formatted disk images

#181

A friend of mine lost a ton of data this week after mac os crashed and he restarted it. The only things he had done since getting the computer a week ago were: 1. update to high sierra 2. copy over files from old mac 3. record about 40gb of screen share data using quicktime (which is what he was doing when it crashed) He spent hours on the phone with apple, the tech said he had never seen anything like it and they we…

Lost a ton of data? Doesn't he use Time Machine?

Re: MacOS may lose data on APFS-formatted disk images

#182

Earlier quoted context omitted.

>Stop dismissing legitimate complaints just because you worship "new and shiny" Yeah, right after you stop dismissing important security updates as "new and shiny".

No, he’s right. Whilst there was a bit of criticism of Windows XP, most people were fine with it and it was widely praised. Same with Windows 98. In fact, Windows ME, Windows Vista and Windows 8 were widely criticised when they came out for good reasons, and Windows 7 and Windows 10 were widely praised.

> Whilst there was a bit of criticism of Windows XP, most people were fine with it and it was widely praised.

It didn't start out that way. It was heavily criticized in the first instance. Certainly until SP1 was released.

Re: MacOS may lose data on APFS-formatted disk images

#183

Earlier quoted context omitted.

>How do you know that? Can you point to any other APFS issues that were reported before this one?

My wife's laptop suddenly decided that the boot drive was corrupt a few weeks after she updated to APFS. None of the recovery tools were of any use. We had to reinstall the OS and pull the files from a backup. This story did not make it to Hacker News.

I thought Diskwarrior supported APFS - did you try that one?

Re: MacOS may lose data on APFS-formatted disk images

#184
post #181

A friend of mine lost a ton of data this week after mac os crashed and he restarted it. The only things he had done since getting the computer a week ago were: 1. update to high sierra 2. copy over files from old mac 3. record about 40gb of screen share data using quicktime (which is what he was doing when it crashed) He spent hours on the phone with apple, the tech said he had never seen anything like it and they we…

Lost a ton of data? Doesn't he use Time Machine?

Yes, although he was traveling so he wasn't able to recover until he returned home and even then, there was a gap in his backup (his fault) and his screenshare recording wasn't backed up since it was done while traveling. Thankfully he had already sent his presentation ahead to the conference he was presenting at, so he was at least able to complete that obligation.

This is a good lesson for everyone... obviously we all know to backup regularly (let Time Machine do its thing multiple times per day of course); but the lesson for me was when traveling, have everything you need backed up on a USB stick at least.

Re: MacOS may lose data on APFS-formatted disk images

#185

A friend of mine lost a ton of data this week after mac os crashed and he restarted it. The only things he had done since getting the computer a week ago were: 1. update to high sierra 2. copy over files from old mac 3. record about 40gb of screen share data using quicktime (which is what he was doing when it crashed) He spent hours on the phone with apple, the tech said he had never seen anything like it and they we…

I had a kernel panic a few weeks ago that left the OS in a state where it was unable to boot. It seemed to think it was mid-upgrade and was complaining about missing the packages an upgrade would read from. Thankfully macOS has an in-place OS reinstall option and as far as I’ve been able to see all my data is totally fine. But it was bizarre and I’ve never experienced anything like it in a decade of using Macs.

Everything running fine now after the OS reinstall?

Re: MacOS may lose data on APFS-formatted disk images

#186
post #181

Earlier quoted context omitted.

Lost a ton of data? Doesn't he use Time Machine?

Yes, although he was traveling so he wasn't able to recover until he returned home and even then, there was a gap in his backup (his fault) and his screenshare recording wasn't backed up since it was done while traveling. Thankfully he had already sent his presentation ahead to the conference he was presenting at, so he was at least able to complete that obligation. This is a good lesson for everyone... obviously we…

Yeah, traveling would get you :( poor guy. Backblaze or something may have helped slightly with that (not the screenshare recording, if it was too big).

And yes, a high capacity USB stick. There are very small thumb drives that you can permanently leave in the USB-port of the laptop. Unfortunately I haven't found one like that with a USB-C connector.

Re: MacOS may lose data on APFS-formatted disk images

#187
post #168

Earlier quoted context omitted.

It’s not about not being able to port it; it’s not the right tool for the job. ZFS is a file system designed for servers; the Apple Watch, Apple TV and the iPhone and iPad aren’t servers.

That doesn't mean it can't be adapted and tuned for mobile. The average smartwatch has more processing power than the average server did at the time the ZFS project was launched (2001).

+1 to that. Or at least some subset that speaks the ZFS-protocol if such a thing exists.

Re: MacOS may lose data on APFS-formatted disk images

#188

APFS not having block or file-level checksums really seems like a big oversight to me. While the filesystem’s designers considered the hardware-level guarantees to be sufficient [1], this issue shows that there is an entire class of problems that they have not considered. Disk images and loopback-mounted filesystems or even disk-level cloning introduce additional layers of complexity where a filesystem can be silentl…

APFS not having block or file-level checksums really seems like a big oversight to me. It wasn't an oversight; it was a deliberate design decision. Others replies have noted that maybe it was a performance issue, etc. But I think it's something much different. The real reason is that there is more downside than upside to reporting these errors. Users would be very upset if iOS told them that there was a bad block in…

That's not really any better. That just supports the narrative that Apple only cares about frivolous uses of their devices ("toys") and aren't serious about supporting Pro users (who will definitely want to restore corrupt files from backups)

Re: MacOS may lose data on APFS-formatted disk images

#189

> To prevent errors when a filesystem inside of a sparse image has more free space than the volume holding the sparse image, HFS+ volumes inside sparse images will report an amount of free space slightly less than the amount of free space on the volume on which image resides. Can anyone explain the "slightly less than" part of this? Why wouldn't it just be "equal to"?

To account for filesystem metadata?

Re: MacOS may lose data on APFS-formatted disk images

#190

Earlier quoted context omitted.

>How do you know that? Can you point to any other APFS issues that were reported before this one?

I have an iPhone 6+ that's stuck in an infinite boot loop. Everyone thinks it's a BGA solder ball failure on the NAND flash part. Can you be 100% sure it's not an APFS fuckup?

to be fair, BGA solder joint issues are ridiculously common on that model. to the point that, as someone who's services phones for years, i warn people away from them even if they're dirt cheap
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