[magnetic]

Or...

You put the 2 TB drive somewhere else (at a relative's) and keep it updated regularly via network.

That's my set up (but with a bigger drive).

At home, I have the master copy of the data on my file server. Then I have backup #1 that is in the same location and backup #2 that is in a different location.

Both #1 and #2 get updated at night with a "timemachine-like" backup system based on rsnapshot. The network traffic goes over ssh.

Remote backup system #2 cost a UPS, a RaspberryPi and an 8 TB drive, which is about ~$250-$300 total.

The initial sync is best done locally of course, but deltas can generally easily go over network at night.

Cheap, reliable, and (relatively) easy (if you're a geek, that is).

[parliament32]

I remember there being software back in the day that did exactly this.

The name escapes me right now, but basically you had to add "friends" in the software, then dedicate a certain amount of HDD space to it. It would then back up your files to your friends' computers, and theirs to yours. Backups were encrypted so your friends wouldn't be able to see your files.

It was a super neat idea, I wish I could remember what it was called so I could see if they're still around...

[ajb]

There's an open source one called Tahoe: https://tahoe-lafs.org/trac/tahoe-lafs There used to be a company with a more usable similar product called allmydata, but it seems to be defunct.

[riobard]

What happens if you move/rename a bunch of big files?

[beagle3]

Nothing bad, if you use "bup" or "borg"; The latter has better delete support, so is a better choice for rolling backup if you sometimes delete data. "bup" has the advantage that its repo format is git, which makes it easier to hack.

Both use rsync-style deltas to only send changes, but they use a content-addressable scheme like git so renames are a small metadata change record.

Also, both offer ftp and fuse interfaces if you need to access an older backup.

[magnetic]

Bad things! rsync isn't smart enough (AFAIK) to know that files have been renamed or moved: it just sees files disappearing on one side and appearing on the other side, so the daily delta can get big.

[riobard]

Yeah that sucks…

I'm looking into using the incremental diff/snapshot feature of btrfs to implement a more efficient solution :P

[magnetic]

DRBD may be a good solution to this problem, although I haven't spent the time to see what it would take to replicate over ssh, and the kind of traffic that is incurred vs changes in origin.

https://en.wikipedia.org/wiki/Distributed_Replicated_Block_D...

[riobard]

Interesting! Never heard of this before.