What actually counts as a copy under the 3-2-1 rule, why a RAID mirror or a snapshot only protects against one kind of failure, and the one-page inventory that exposes the gaps.

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[–] 1 point 1 day ago

I hate this take, and it seems to contradict itself.

What actually counts A copy counts when it survives the loss of the thing it was copied from. That one sentence settles most arguments about what is and isn't a backup.

So doesn't raid count then? If a drive fails and the second drive survives the loss, it is a backup...

Just because the copy is synchronous doesn't mean it isn't a backup, it just means it protects from a different type of failure.

  • RAID: protects against a drive failure
  • Snapshot: protects against user failure (rm *)
  • Replication: protects against admin failure (zpool destroy)
  • Offsite tape/async backup: protects against replication corruption, and total site failure

These are all backups, just with different recovery point objectives/recovery time objectives, and all just as important.

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  • [–] 3 points 3 days ago

    Sloppy, somawhat difficult to read. Should use a model that's better at writing English. 😄

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  • [–] 1 point 4 days ago

    Bold of you to assume I can afford backups, or redundancy

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