FTP hangs up reading folder


I have purchased the optional feature for FTP using Secure TLS Explicit connection. It works ok, but I am having an issue I hope some one can help with.

Sometimes there is long lag refreshing the remote directory. For example, I might upload an updated html page and file transfer occurs immediately and then DOPUS is doing a refresh of the remote directory and it takes many seconds to perform the refresh. This is annoying and other FTP programs, e.g., FileZilla and WinSCP perform the remote refresh almost instantly. Is there a setting in DOPUS that resolves this issue?



Have you tried everything in the FTP FAQ?

Make sure Passive mode is turned on, and check what the log is reporting.

Thanks for getting back, Leo.

I have passive mode turned on. There is nothing in the log that seems out of place.

I just logged in to the FTP site, when to the directory and then merely uploaded three html pages. They upload fine and then it takes over 60 seconds to refresh the folder. During the refresh time, a message is displayed that says ... "Reading folder ... " and green bar that cycles left to right and a button to Abort. If I click the Abort button, it merely stops the refresh.

Reviewing the FTP FAQ and everything seems OK. I have another FTP client that seems to work very well ... WinSCP. Checked the settings and they appear to be same setup as I am using in DOPUS.

This long refresh time is really annoying and other FTP clients do not experience this.

WinSCP supports are few different protocols. Are you using the same protocol and other settings in both programs?

What does the log say during and after the delay?

During the delay the log says ...

257 "/public_html/testing.forzacomponenti.com" is your current location
250 OK. Current directory is /public_html/testing.forzacomponenti.com/images
257 "/public_html/testing.forzacomponenti.com/images" is your current location
227 Entering Passive Mode (72,18,134,36,136,174)
150 Accepted data connection

after the delay the log has these additional lines of text ...

RDIR NO FD_CLOSE Response from Server
7127 bytes received in 71.16 seconds (0.0 Kbytes/sec)
226 57 matches total

I think "NO FD_CLOSE Response from Server" means the server side isn't closing the socket after sending the directory listing, which Opus is waiting for. At least as far as I understand it, it may indicatea bug in either the FTP server or something in-between the two machines (firewall/antivirus software or other network hardware/software) that might be messing things up.

WinSCP and FileZilla seems to handle this just fine. No issues. It seems curious that DOPUS does not. I can only conclude something is amiss with DOPUS or there is some setting in DOPUS that may need tweaking. I find it far less likely to believe there is something amiss with the server, firewall, antivirus, network when two applications handle the FTP just fine and one does not. Don't you agree?

It's possible there's an issue in Opus, but pretty much every other FTP sever works fine with Opus and it's also possible the server (or something in between) is doing something wrong which the other clients are more forgiving about than Opus is. It's also possible for firewall software to recognise WinSCP and FileZilla and treat them differently to Opus, which could mean Opus is being blocked from receiving data from the server and the other software isn't (although the log suggests the data is being received and the socket just isn't being closed).

Failing to properly flush and close data sockets after sending data is definitely a bug in some network servers (not just FTP ones).

I am having the exact same problem for some time now.
Ftp server is windows server 2012.
When it starts to hang if i click abort and then try process again it works straight away.
If i upload again quickly it works.
But if i leave it for a minute or 2 it hangs again.

FYI i am using Explicit TLS

What do your logs say?

Are you using Passive mode?

Yes i am using passive mode.
It gets stuck on "Changing Folder" for about 30 seconds. Then works fine until it is left idle for a while.
250 CDUP command successful.
257 "/" is current directory.
FD_CLOSE - WSAECONNABORTED: Software caused connection abort
Connection closed
Timeout on Command 1005.
Opening Connection ...:21
220 Microsoft FTP Service
331 Password required
230 User logged in.
200 Type set to A.
257 "/" is current directory.
250 CWD command successful.
257 "/aspnet_client" is current directory.

That implies something is closing the connection unexpectedly. Could be firewall related, perhaps.

It's actually the opposite problem to what the rest of the thread was about, where the data connection isn't being closed after all the data is sent.