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Comment by Hackbraten | Hacker News Reader

Ironically, kexts allow me to have better backups in the first place. APFS won’t check for bit rot, nor does it allow to make snapshots. OpenZFS enables both, and works with a kext. I don’t know whether Apple will allow that use case in the future.

I don’t like the way this is going.

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You can definitely make snapshots on APFS. It also use checksums for filesystem integrity.

> You can definitely make snapshots on APFS.

Apple can. I can’t. Making APFS snapshots requires special entitlements, which they’re not going to give me.

> It also use checksums for filesystem integrity.

It doesn’t check integrity of the actual data though. But I care about my data.

You can use tmutil to create a snapshot.

Or do you want to create an app that performs a snapshot via some API.

One does not simply create an APFS snapshot using tmutil. Using tmutil means Time Machine creates a snapshot for me. It also conveniently earmarks the snapshot for later removal at Time Machine’s own discretion.

That’s not what I want. I want to have a say in snapshot retention, not have some tool make the decision for me.

Specifically, I need precise control over snapshot retention so I can maintain several off-site replicas of my backup.

> Apple can. I can’t. Making APFS snapshots requires special entitlements, which they’re not going to give me.

What makes you think that? Carbon Copy Cloner does this, and is made by a small independent developer.

https://bombich.com/kb/ccc6/leveraging-snapshots-on-apfs-vol...

They have managed to obtain the special entitlement.

Source: https://bombich.com/blog/2018/03/30/building-better-backups-...

They’re one of two apps in the world who have been granted the entitlement as far as I know. The other one is Time Machine.

APFS does NOT checksum the same as ZFS. APFS relies on the SSD controller to checksum/safeguard data. Which is fine so long as all your data is on SSD :p

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