Synchronize folders from Pixel 7a (Android 14) and Linux PC (Kubuntu 22.04)

wired

I am currently setting up a new phone (Google Pixel 7a) with GrapheneOS (Android 14) and am looking for a way to synchronize individual folders of the phone with individual folders of the Linux PC (Kubuntu 22.04 LTS), preferably bidirectional, preferably only in the home network (WLAN).

Background: I want to automatically transfer files and photos to the PC and delete or add files and photos deleted or added on the PC to the phone.

How could I proceed? Which programs do this?

TheGodfather

wired

Syncthing or resilio sync for direct sync.
Or use a cloud for indirect sync.

[deleted]

TheGodfather

Syncthing syncs deletions as well, which surprised me when i found out i completely lost a valuable folder...

I prefer to use rsync via Termux and MTP with devices i trust.

wired

TheGodfather
Phead

Many thanks for the tip!

After some testing, I can say that Syncthing works very well for me and does exactly what I want.

However, now I'm wondering if and how to synchronise multiple GrapheneOS users from 1 phone to 1 PC. So far, I have only found the target directory on the PC under Actions > Advanced > Default folder > Path. But I can't create two paths, one for user#1 and another for user#2.

Or am I on the wrong path? Is it possible to synchronise two phone users with one PC?

Phead

Syncthing. But make sure to read the manual and uncheck global discovery.

Arnauld

Phead uncheck global discovery

Where can I do that? On the phone or computer? And why?
Thank you.

Titan_M2

Arnauld Where can I do that? On the phone or computer?

Both.

Arnauld And why?

I assume because global discovery allows deriving your IP address via the device ID. Not a big deal since the ID can't be guessed but you should disable if you only want LAN sync.

Phead

Arnauld

On both devices.
From the Syncthing manual:

Should I keep my device IDs secret?

No. The IDs are not sensitive. Given a device ID it’s possible to find the IP address for that device, if global discovery is enabled on it. Knowing the device ID doesn’t help you actually establish a connection to that device or get a list of files, etc.

For a connection to be established, both devices need to know about the other’s device ID. It’s not possible (in practice) to forge a device ID. (To forge a device ID you need to create a TLS certificate with that specific SHA-256 hash. If you can do that, you can spoof any TLS certificate. The world is your oyster!)

If you don't need it turn it off for ease of mind.

Arnauld

Titan_M2 Thank you, I didn't know that, I turned it off.

Arnauld

Phead Thank you. I turned it off anyway.

TheGodfather

Syncthing syncs deletions as well, which surprised me when i found out i completely lost a valuable folder...

OP wants bidirectional sync, which usually also includes deletions.

Titan_M2

Syncthing syncs deletions as well, which surprised me when i found out i completely lost a valuable folder...

Well, that’s the meaning of synchronization. You can also set a folder on the phone to be send only and on the computer to receive only.

rufus

thats my favorite for syncing folders:
https://freefilesync.org