Today I update one of my devices to RC v1.4.0-rc.1 and all data are lost. If I can store all settings and import later, no problem, but in such way any update on servers etc. is not possible!
For that device I have to setup all content like for a new installation.
This is neither intended behavior nor did it happen to me when it upgraded this morning.
If the config seems to suddenly “be gone”, it is possible that the home directory has changed (e.g syncthing is running under a new user account or similar).
Also, what OS do you run on the affected device?
Just an idea: st-config-autobackup-20200211.zip, st-config-autobackup-20200212.zip, …
That’s over cautious but probably makes sense at a future point. I’ve never required restore from auto backups e.g. in Firefox before but find it a useful second safety line.
On the other hand, I’m checking my st text config files into git and can recover any time. Not too much work to do :-).
I hope you’ve got a clone or other place where you could get your config back from.
What does “all data lost” mean, specifically?
All data lost means all connections lost, i.e. folders and devices. The directory contents themselves were all still there.
The installation was set to default after the update. All folderinformation and devices were gone and had to be reconnected. In this case it was not a bad thing, the external devices were immediately offered again and the directories were quickly reconnected.
It was a Windows 10 computer with only a few connections. If this had happened on one of my servers, the effort would be more much extensive.
Can I make a backup of the working folder
C:\Users\xxx…xxx\AppData\Local\syncthing
as backup to restore it in such cases? Or is to store the “config.xml” enough?
If possible, I make a second test on a other windows computer as test.
So config.xml was lost, but keys, database etc in the same directory was still there? config.xml.v29?
Restoring the index database from a backup isn’t generally a great thing to do. I recommend not doing it and instead just rebuilding and dealing with the eventual conflicts if disaster strikes…
Mines hanging on upgrading to 8 (synctrazor). But 1.3.4 stock St won’t load at all.
It’s likely not hanging, it just takes a while. There’s a database transition happening on upgrade to 1.4.0, which may take some time.
On a second Windows 10 computer the update was okay, all settings are as before. Is there in any time a update of database or only now with v1.4.0? I make a further test on a third Windows 10 computer.
Not every time. And a db update means a bump in Y vX.Y.Z (however not the other way round, Y may also be bumped for a conig change without a db transition).
I made the update to v1.4.0 rc2 on all Windows 10 devices with success.
Windows 10 with synctrayzor, automatic upgrade happened some time in the past couple of days - I also lost all folders and devices - but the private key etc were still there, so the rest of my fleet (still on 1.3X) reconnected to the amnesiac node and I just needed to accept all the “X wants to connect”, “X wants to share a folder” prompts.
Looking at logs, no mention of any panic, just “everything is fine (messages about connecting and disconnecting from known peers)” upgrade “everything is broken (messages about rejecting unknown peers)”
[SMNSD] 10:11:18 INFO: Automatic upgrade (current "v1.3.4" < latest "v1.4.0-rc.1")
[SMNSD] 10:11:45 WARNING: Automatically upgraded to version "v1.4.0-rc.1". Restarting in 1 minute.
[SMNSD] 10:12:45 INFO: QUIC listener ([::]:22000) shutting down
[SMNSD] 10:12:45 INFO: Relay listener (dynamic+https://relays.syncthing.net/endpoint) shutting down
[SMNSD] 10:12:45 INFO: Disconnected from relay relay://37.122.210.202:22067
[SMNSD] 10:12:45 INFO: Connection to 5T4LX5E at 192.168.5.27:49501-192.168.5.77:22000/tcp-client/TLS1.3-TLS_CHACHA20_POLY1305_SHA256 closed: Syncthing is being stopped
[SMNSD] 10:12:46 INFO: TCP listener ([::]:22000) shutting down
[SMNSD] 10:12:46 INFO: Exiting
[monitor] 10:13:05 INFO: Log output saved to file "C:\Users\Shish\AppData\Local\Syncthing\syncthing.log"
[monitor] 10:13:05 INFO: Default folder created and/or linked to new config
[start] 10:13:05 INFO: syncthing v1.4.0-rc.1 "Fermium Flea" (go1.13.7 windows-amd64) teamcity@build.syncthing.net 2020-02-10 09:48:30 UTC
[start] 10:13:05 INFO: Default folder created and/or linked to new config
[start] 10:13:05 INFO: Default config saved. Edit C:\Users\Shish\AppData\Local\Syncthing\config.xml to taste (with Syncthing stopped) or use the GUI
I don’t see any backup copies of config.xml anywhere 
The same at me, but without synctrayzor.