Synchronization: Reconnect and continue during file compare.

Synchronization has two phases.
First it compares local and remote directories to find differences.
Then it transferes files that are different.

Sometimes during synchronization the server disconnects.
If the synchronization has reached the transfer file phase then it reconnects and continues transfering files where is stopped.
On the other hand if synchronization is still comparing local and remote directories then it does not continue.

If a disconnect happens during the compare phase, I would like winscp to reconnect and continue to compare directories where it left off.
Parameters to use for the compare reconnect could just be the same as exist already for file transfer reconnect.

Thanks
JH

Thanks for your post.

This request is being tracked already:
Issue 25 – Automatic reconnect during any operation

Thanks for your reply.

Such are the wonders of the Internet. You search for hours to find a solution or if someone has had the same problem, and you still do not find anything!

After reading the tracking tickets I can see this is a 4 year old subject that has not been addressed yet.

My situation in more detail is this:

I am using a script to synchronize a website over FTPS (exsplicit TLS). Because of some unknown reason the servere disconnects in less than 5 minutes (usually between 2 and 3). If the directory listing takes more time than this, the script stoppes. If it reaches the file transfer phase, it synchronizes but with repeated disconnects and reconnects. As I have many files, the synchronization never reaches the file transfer phase, except for the first time, when there was nothing on the other end.

I then tried using plain FTP (no encryption) and then the server did not disconnect and everything ran as exspected. But this is not an acceptable solution. Need encryption.

I have tried the FTPS transfer agains servers in both USA and Germany and both disconnect.
I have also tried FTPS with FileZilla and it also disconnects regularly. I had to split my large manual transfer into smaller batches.

It might be an error / misconfiguration in my firewall, but this will be hard to track.

Anyhow it would be great to have the reconnect option during directory compare.


Thanks for a great program,
JH

For anyone than might find this thread.

Found a solution to the disconnect problem.
The Windows 7 firewall is messing with the FTPS traffic.

Run
as an administrator and all disconnect problems are gone.
This only disables some parameters for FTP, not the complete firewall (although that is an option too).

See
https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-R2-and-2008/dd421710(v=ws.10)
https://stackoverflow.com/questions/6990663/java-7-prevents-ftp-transfers-on-windows-vista-and-7-if-firewall-is-on-any-idea
for further information.

Although the disconnect problem is solved, I still would like to have a reconnect during the compare directory phase.

Thanks,
JH

Thanks for sharing your solution!

Just to chime in and thank the original poster.

Had same issues with disconnects every 2–3min.
Fixed using the suggested command, cheers!

What specific error message were you getting? So that I can document this.

Refer to documentation for details on disabling stateful FTP filtering to overcome the FTP disconnects:
https://winscp.net/eng/docs/message_disconnected

Is there any progress on auto-reconnect during compare? The linked feature request (Issue 25 – Automatic reconnect during any operation) is marked as resolved, but it looks like the fix was implemented only for file listing. Maybe the issue should be reopened? I would really like this feature.

@andreasxp: Comparing is mostly about listing. So that's why it's marked as resolved. Does your connection break in other situations? Please attach a full session log file showing the problem (using the latest version of WinSCP).

Sorry for the late response. I've attached the log file. Unfortunately the full log was over 500MB, so I had to delete a lot to upload it here. I've left the first ~250000 lines, and you can see the an internal server error happens at line 220099, after which WinSCP does not retry and asks me to retry manually. Let me know if you need the full log, I can upload it to some cloud and share a link.

OK, but this is rather specific case. How can WinSCP tell that the "internal server error" is an intermittent problem? WinSCP just gives up, assuming the problem is permanent.

I see. Then, could we perhaps get an option, so that a user can tell WinSCP whether it should retry or not? And/Or an option to specify an amount of retries before WinSCP gives up on this error?

OK, we will consider that.