Time Machine-style backups with rsync (2018)

If we spoke about a Linux box, one that prudently ran ZFS, or XFS on top of LVM, it would be possible to make a snapshot before the diffing and sending, so that the snapshot would be indeed point-in-time. IDK if whatever macOS uses for the filesystem supports snapshots.

Otherwise, I think, restic or kopia are better for proper backups, and Syncthing for keeping a mirror copy. But the simplicity of this script in charming.

Re: Time Machine-style backups with rsync (2018)

#5

Post by orev » Mon, Feb 02, 2026, 1:22 AM UTC

The original post that introduced this idea into general public: http://www.mikerubel.org/computers/rsync_snapshots/

I’m sure others will chime in that they used hard links like this before then, however as noted in that page, it’s the one that made it popular enough that rsync was updated to support the idea natively.

Re: Time Machine-style backups with rsync (2018)

#6

Post by hughc » Mon, Feb 02, 2026, 1:25 AM UTC

I've been using a bash encapsulation of this for a long time, works great.

https://github.com/laurent22/rsync-time-backup

Re: Time Machine-style backups with rsync (2018)

#7

Post by kunjanshah » Mon, Feb 02, 2026, 1:53 AM UTC

nightshift1 wrote: post #3

Seems similar to https://rsnapshot.org/

This is the more robust way to go. Uses rsync under the hood.

Re: Time Machine-style backups with rsync (2018)

#8

Post by EGreg » Mon, Feb 02, 2026, 1:54 AM UTC

Why make hard links when you can use rsync or syncthing to just make an actual copy on an external hard drive eg via wifi or just remotely?

Re: Time Machine-style backups with rsync (2018)

#9

Post by crossroadsguy » Mon, Feb 02, 2026, 1:58 AM UTC

mrtesthah wrote: post #2

Isn’t restic better for backups overall? Anyone have a good script for macOS triggered by launchd, ideally something that uses FSEvents to check for directory changes?

Yes, it is; among a few other great cross-platform FOSS tools that are built just for backups, and they do it really well. But most of them do periodic scans (as opposed to file change trigger-based backup runs, which I guess is what you might be looking for, I assume by your second sentence).

Re: Time Machine-style backups with rsync (2018)

#10

Post by kej » Mon, Feb 02, 2026, 2:12 AM UTC

EGreg wrote: post #8

Why make hard links when you can use rsync or syncthing to just make an actual copy on an external hard drive eg via wifi or just remotely?

The hard links are to the most recent backup before the one happening now in the script, so that you aren't storing full copies of files that haven't changed between backups.