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Comment by terminalserver | Hacker News Reader

For anyone reading this..... macOS has Time Machine.... you just plug in an external usb disk as big as you can afford, tell time machine to use it, and it backs up your stuff in the background. There’s no excuse for losing data cause your primary disk crashes.

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time machine uses snapshots, which might take your disk space away if you do not know it. just for anybody wondering why they do not have any disk space left of their 1tb drive, besides only using like 400g

The disk space used for snapshots is automatically re-claimed by the OS when it's needed by the user. The trade off is near-instant backup images.

And while MacOS sometimes has issues expediently clearing space the was previously used for snapshots, tools like DaisyDisk and others can force its hand if you need.

Bottom line, you don't lose available disk space by using Time Machine.

That’s the theory, and it works like that on my MBP. But for some reason on my old iMac, snapshots used to just accumulate and every so often things start crashing because there was no space left, causing all sorts of issues. Sometimes the OS couldn’t boot because of that, it really was a pain.

And yes, you can nuke snapshots preemptively, but often the first visible sign was Mail having corruption issues because it’s database was borked, at which point it was too late.

Even better, use Time Machine to a NAS! You can have redundant drives, in case one dies!

Migrating Time Machine backups from a USB drive to a network share is not supported, but it's doable, not impossible. (This is something I've done before, and in fact I'm doing this for family right now.)

I've had nothing but trouble with time machine..

Time Machine can't run on my Mac because there's not enough space on disk for it to run. Third party backup services that can function with the comically small default SSDs are preferable.

> Time Machine can't run on my Mac because there's not enough space on disk for it to run.

If your Mac HD is that low on space, you're going to be getting horrible performance. You should sort that out and try to keep around 10% free.

And Time Machine deletes data if it runs out of disk space.

Do NOT trust Time Machine. Back up your data.

And restore it once in a while.

"Backups not issue. Backups very boring. Restore is issue. Restore very exciting."

No backup scheme can keep storing data once the disks are full… TimeMachine is fine to restore a computer to its state a day or a week ago (say, before an OS update or to transfer data to a new device), and to get some documents up to a couple of months back if the backup drive has the recommended size. It’s not a professional tool designed to restore a whole computer to the state in which it was 2 years ago.

But yes, you need to check that it can restore every now and then.

There is a difference between "quit storing data" and "delete old data" when full.

Time Machine deletes old data. That is not a good backup plan.

It’s not the same use case. When your computer kicks the bucket and you need to transfer your data to a new one you don’t care about documents from 5 years ago. If your backup does not have your state from yesterday you’re screwed.

Time Machine is not a long term backup, it’s a safety net.

There's no evidence the disk crashed in this case.

Access to the disk and data was lost.

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