Put file on .NET CF timeout exceeded with GPRS/3G connection

0 votes
asked Jan 6, 2012 by motorollie (120 points)
edited Jan 11, 2012

Hi,

Logging:

2012-01-06 16:35:23 INFO Ftp(1) Command: STOR xxxxxx.xxx
2012-01-06 16:35:24 INFO Ftp(1) Response: 125 Data connection already open; Transfer starting.
2012-01-06 16:35:24 DEBUG Ftp(1) Info: Closing uploading data connection.
2012-01-06 **16:35:28** DEBUG Ftp(1) Info: Waiting for data transfer ending message.
2012-01-06 **16:36:28** INFO Ftp(1) Info: Timing out.
2012-01-06 16:36:28 ERROR Ftp(1) Info: Error while closing data connection: Rebex.Net.FtpException: Timeout exceeded.

I'm getting a timeout when uploading small files (1 kB) through a 3G connection on a WM 6.1 device. Uploading larger files (60-90 kB) seems to be fine and also no problems with downloading. Any ideas? It waits for 1 minute... this should be enough I guess.

The connection is also running through VPN with the Cisco VPN AnyConnect Client v2.5.0217

ftp.Options = FtpOptions.KeepAliveDuringTransfer; << Does NOT work

Below logging from an upload of a 90 kB file, which is OK;

2012-01-06 16:30:11 INFO Ftp(1) Response: 227 Entering Passive Mode (xx,xx,xx,xx,xx,xx).
2012-01-06 16:30:11 DEBUG Ftp(1) Info: Establishing data connection to xx.xx.xx.x:5559.
2012-01-06 16:30:12 DEBUG Ftp(1) Info: Enabling socket linger option.
2012-01-06 16:30:12 INFO Ftp(1) Command: STOR xxxx.xxx
2012-01-06 16:30:13 INFO Ftp(1) Response: 125 Data connection already open; Transfer starting.
2012-01-06 16:30:19 DEBUG Ftp(1) Info: Closing uploading data connection.
2012-01-06 **16:30:26** DEBUG Ftp(1) Info: Waiting for data transfer ending message.
2012-01-06 **16:31:17** INFO Ftp(1) Response: 226 Transfer complete.

It also takes very long (51 seconds) to receive the transfer complete. How is this possible?

Below logging from a download;

2012-01-06 16:26:39 INFO Ftp(1) Command: RETR xxxxx.xx
2012-01-06 16:26:39 INFO Ftp(1) Response: 125 Data connection already open; Transfer starting.
2012-01-06 16:26:40 DEBUG Ftp(1) Info: Data transfer ended.
2012-01-06 16:26:40 DEBUG Ftp(1) Info: Closing downloading data connection.
2012-01-06 **16:26:40** DEBUG Ftp(1) Info: Waiting for data transfer ending message.
2012-01-06 **16:26:41** INFO Ftp(1) Response: 226 Transfer complete.
2012-01-06 16:26:41 DEBUG Ftp(1) Info: Data transfer ended.

Transfer complete is received within a second!

commented Jan 9, 2012 by motorollie (120 points)
edited Jan 9, 2012

I did some additional testing... file size does not seem to matter. The upload randomly fails. Sometimes the upload is successful, but in most cases it times out. This behaviour is seen with passive and active mode.

1 Answer

0 votes
answered Jan 11, 2012 by Lukas Pokorny (101,070 points)

Have you tried using any third-party FTP clients? That would make it possible to tell whether there is some issue in Rebex FTP causing this, or whether something is wrong with the underlying connection. Try Total Commander, for example: http://www.ghisler.com/pocketpc.htm (includes an FTP client).

commented Jan 11, 2012 by motorollie (120 points)
edited Jan 11, 2012

Lukas,

Thanks for your reply. With TotalCommander this issue does not occur. So it seems to be Rebex. I have Wireshark traces from both Rebex and TC on the server side. Can I email the traces for you to have a look?

commented Jan 11, 2012 by Lukas Pokorny (101,070 points)
edited Jan 11, 2012

Yes, please do! That should make it possible to tell what is going on. E-mail the logs to support@rebex.net

...