restic 0.17.3 compiled with go1.23.3 on linux/amd64 (Debian 12)
This is more of a request for advice. I have a couple Macs that use Time Machine to backup to a NAS. I currently use restic to backup several other directories on this NAS to Backblaze B2 which works great.
Knowing that Time Machine works by creating hard links and hard links are mapped to inodes on a filesystem - I’m wondering if anyone knows if I’d run into problems using restic to create backups of my Time Machine directories in B2.
Thanks
This was many years ago when Time Machine used HFS+ filesystem. Nowadays all is done using APFS and snapshots.
Regardless of the above remark Time Machine backup on your NAS is encapsulated within sparse bundle disk image. No hard links, no snapshots - effectively just many small files (with all Time Machine magic happening inside). From restic backup perspective there is nothing you have to worry about - just backup it wherever you like.
One thing you should take care of is to ensure this image backup integrity. Do NOT backup anything when Time Machine is in use - not just running backup but even opened on your mac computer or indexing in the background. If you do then your backup is most likely useless and you waste your time and money:) as it won’t work when restored.
What you could do is to create on your NAS Time Machine directory filesystem snapshot when there is no active SMB connection and use it as a backup source. If you are using TrueNAS such snapshots are created automatically, other NAS systems do your research. It is out of restic scope though. Google is your friend here.
Thanks! I’ll have to figure something out to make sure that I’m not working on the directory unless it’s idle or look at creating a snapshot of some sort.
I appreciate the insight.