So here’s the thing that drives me crazy.
Having had a hard disk die on me a few years ago, I’m a little paranoid about backups. I have three:
- Time Machine, over WiFi to a Synology NAS
- Backblaze, “cloud” backup over the internet
- SuperDuper clone to an infrequently connected USB hard disk
Time Machine and Backblaze run all the time, nice, seamless and hopefully pretty complete. I do the SuperDuper clone occasionally and every few months I try to reboot and check that the clone actually works.
And that’s where the problems start.
If I forget to turn off WiFi — which I almost always do — then when the clone starts up, it immediately connects to WiFi and starts to back up to Time Machine. I panic and stop it as soon as I realise.
But then I boot back to my main disk and… Time Machine decides it needs to do a full backup. Which. Takes. Forever. (Backblaze is also doing a huge backup, presumably for the same reason.)
What’s the answer to this? Is there a way to switch off WiFi on the clone automatically? Only start when the boot disk has a specific name? I don’t know! It’s hard to search for because I can’t think what the answer might be.