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Signal Secure Backups

(signal.org)
988 points keyboardJones | 1 comments | 08 Sep 25 16:43 UTC | HN request time: 0.231s | source
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poisonborz ◴[08 Sep 25 17:34 UTC] No.45171210[source]▶
Backing up Signal on Android for free and offline was ~always possible. The app creates a multi GB backup file on the phone memory under the Signal folder that you can just copy out and back on a new phone.

The file is encrypted with the passcode and the database can be extracted.

https://github.com/bepaald/signalbackup-tools

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Sesse__ ◴[08 Sep 25 17:46 UTC] No.45171393[source]▶
There are a couple of problems with the existing backup:

1. It is non-incremental. This means you'll need about as much free space on your phone as your Signal database takes, and it may take many hours to make if your database is large (mine is 18GB). I used to wake up to find my phone had not even fully charged because it had been so busy writing Signal backups.

2. Once you have it on disk, how do you get it away from your phone? Especially after SyncThing disappeared from Play Store (because it was basically a non-Android app behind a thin Android shell that couldn't easily be upgraded to more modern native APIs), there's nothing super-obvious here.

I would have loved a better solution for local backups, but realistically, $2/month for cloud backup is really cheap, and a pragmatic solution.

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autoexec ◴[08 Sep 25 18:03 UTC] No.45171645[source]▶
> Once you have it on disk, how do you get it away from your phone?

plug your phone into a computer? Install Termux and use one of the countless command line programs designed to transfer bits over a network?

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1. codethief ◴[08 Sep 25 22:45 UTC] No.45175103[source]▶
I think GP was talking about how to transfer the backup 1) daily, 2) in an automated manner, and 3) reliably and in time (before, 48h later, Signal overrides the existing backup on your phone later with a new one).

This is not trivial when each backup archive is in the order of 20 GB.