Is syncing a restic repo by only comparing file size a safe thing to do?

Getting Help
1

Hi all,

so I have my restic repo locally which is mirrored via rclone to AWS S3 Deep Glacier. So far so good.

Now, I’d like to try SIA respectively the sia backend for rclone: Sia

Rclone docs state that neither modification times nor checksums are supported.

AFAIK this leaves me only with a detection based on file sizes. Is that enough for a restic repo? As far as I understood restic, every file in the restic repo is immutable and uniquely identifiable. So it should be fine, right?

I am speaking of manually invoking rclone command and not using rclone as a backend for restic, but that question would be also interesting: How does restic deal with rclone backends which only support filesize based comparison?

Best and thanks!

2

This is a nice workaround for the SIA remote limitations. I am sharing here since it might be interesting for others.

However, my initial questions still stand; conceptually-wise.

3

restic never modifies files once written completely (since restic 0.13.0 files are written atomically to a local repository). The filename is calculated as the hash of the filecontent. Thus each file has a unique name. (any modifications to a file would also change the filename)

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