Problem with file transfers freezing

[ChrisEvans2]

Just like in the image, transferring a file of over 800MB gets stuck towards the end. I'm not using a VPN.

[itspacchu]

I have noticed this as well when transferring over 500M

[ChrisEvans2]

I guess it might be an unstable internet connection

[itspacchu]

I was able to scp and keep a websocket active as well only croc was having small tx issues after 90%+

[ElRataAlada]

Same issue. Sometimes it freeze deadly at 70-80% even using a custom relay and a two-way stable gigabit connection. Less than month ago everything was fine

[TheRogueArchivist]

Can confirm this issue, and that they weren't previously present when using older versions of croc. Unfortunately, this is very inconvenient even though the transfers can be resumed, I find myself having to constantly check on transfers to make sure they haven't silently frozen.

[schollz]

@TheRogueArchivist is it reproducible for you? what happens when using --no-local? and are you 100% sure the files you are transferring are not changing?

[TheRogueArchivist]

Well it certainly seems to be happening consistently, I'll be glad to try anything you recommend to see if it improves it. I'm on version 10.2.2 and don't have a --no-local option, there is the --local option though which it says defaults to false. And these files very much shouldn't be changing during the transfer, but I can triple check with the sender if there's any possibility of that.

[TheRogueArchivist]

I just reattempted with default settings, and it froze after it received roughly 1 GB of a 6.1 GB file. Percentage, transferred data, transfer speed, and ETA all stop updating. I confirmed with my friend transferring the file that the file remained 100% unchanged, and that they're also running croc 10.2.2. If you'd like me to test with any other flags or options for the sender/receiver, and I'll gladly run it again. I'm running EndeavourOS (Linux 6.14.6-arch1-1).
16% |███ | (1.0/6.1 GB, 7.7 MB/s) [1m11s:11m5s]

[schollz]

Sorry, I don't know. I've only ever experience that when I transferred a file that was processing or changing. Would be great for croc to check that but it doesn't right now. I can't replicate your issue. I transfer >6gb every day with 0 issues.

[TheRogueArchivist]

Well the files in question very much don't appear to be processing or changing, but if there's any kind of other options, debug setting, or extra logging I should enable to help narrow this down, I'd be happy to.

[schollz]

To just verify that, it would be great for your sender to sha256sum the file before sending, and then after sending (or after error), do another sha256sum on the file.

[Whovian9369]

Hi, I'm the person @TheRogueArchivist was talking about.
I was sending them a Windows 10 ISO (~6 GB) as a test for this issue, and it has repeatedly cropped up over multiple machines sending to them. There is absolutely no way that these files would be able to be changed while they were being sent by croc, and they hashed correctly before and after on my end.

As far as we can tell, the issue lies with croc and not the files. As @TheRogueArchivist asked, if there's any further way to debug this please let us know and we can try it for testing.

[schollz]

what do you mean hashed correctly?

also what happens when croc stops? it errors? or hangs? have you ruled out problems in your network?

[Whovian9369]

what do you mean hashed correctly?

The file hashes as expected via sha256sum -c File.sha256. (File.sha256 in this case is just a placeholder filename for the example.)

also what happens when croc stops? it errors? or hangs? have you ruled out problems in your network?

It seems to just hang as TheRogueArchivist mentioned earlier. No ETA updates, no EOF, etc.
Personally it happens on two different networks when sending to TheRogueArchivist, but I suppose that it could be an issue with their network. How exactly would we test that, though? Are there any croc flags that we could use to debug this?

[TheRogueArchivist]

I can confirm that all of what @Whovian9369 said is accurate, though I believe I've had these issues pop up before I was living in the area with my current network. In any case, even if there are underlying network issues, I don't believe that they should break croc in this way.