[Bug]: SFTPGo + reverse proxy MOVE 502

[terminar]

Real Outcome

Hi,

i "often" got some strange "502 resolve conflict" error which isn't easy to resolve.
I tried to rewrite / restore the local file (change content, change data) and then sync again - doesn't matter, I have to manually remove the files from the backend webdav storage, then re-sync the files from local to remote and then on the next sync, the local storage tries to download the remote files again.

Then - the problem is fixed. I am not sure if this is a bug but I have no other option from within
Obsidian which I am aware of.

Any idea?

Expected Outcome

when 502 conflict is shown, change of local data (with new content + date) should fix the problem

Backend

sftpgo

Steps to Reproduce

Sync
Get error
try to change the data
sync again
same 502 error

Logs

Issue Policies

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[hesprs]

I think this problem could be at server or transmission layer. Error 502 is often related with reverse proxies. I have some questions:

• Are you using any reverse proxies above SFTPGo? If yes, what proxy software (Nginx, Caddy, ...) are you using?
• Can you inspect SFTPGo logs and see whether it logs anything about the 502 error?
• What conflict resolution strategy are you using?

By the way, SFTPGo has a known bug drakkan/sftpgo#2282 that can make Sync Engine malfunction. The bug itself is benign (cannot lead to data loss), but makes the rate of sync conflicts abnormally high. Currently it is fixed but not included in any releases of SFTPGo.

[terminar]

@hesprs Hm, this is a really good catch, thank you for your insight!

• Yes, I use nginx as reproxy to sftpgo
• Logs: that's a problem because I can't reproduce it now - I have removed and resynced the files. Maybe I can reproduce it on another device where I got more 502 errors within the next hours/days
• conflict resolve strategy: rename and keep both (that's why I was confused)

I'll try to log and reproduce it but the hint about the proxy software might be very helpful, thank you very much (again) for your great work!

Regarding the bug with sftpgo - that may be the same case here and may explain why the sync does sometimes double-sync.
I have now updated to 2.7.99-dev on the server, if I have reproduced the problem I'll update this issue.

[what-sudo]

[what-sudo]

I can consistently reproduce this issue; the cause is unknown. I disabled asymmetric storage, but synchronization still fails to work properly.

[hesprs]

@what-sudo Nice, please tell me what service are you using. If you are self-hosting, can you provide the reverse proxy (if exists) and server logs for the 502 error?

[hesprs]

Very possibly related with drakkan/sftpgo#337 and this comment.