> > i'va a problem during download a file from ftp. > > my client download all bytes but i don't recive CMD 226 and the > > donwload don't terminate. > > If the server does not send a response on the control channel > after the file has been sent, before the data channel is closed, > it's a server issue IMO. > Do you know whether the 226 response is actually sent? You can > check that with a packet sniffer such as the free WireShark.
It can also be a firewall issue, they can seriously interrupt and corrupt FTP sessions. I had two issues on the same file before Xmas. It was a six gig zipped VM image, and the transfer kept stopping at about 1.5 gigs and retrying each 90 minutes, all night, causing a lot of bandwidth use. The Sonicwall firewall log showed it had detected an executable compressor Petite (which I used in the past) as a virus and aborted the FTP transfer. This was quite clever, since the VM image was zipped, the firewall was obviously decompressing the six gig zip on the fly during download. Worse, the Sonicwall firewall was corrupting the FTP REST command, changing the S to a *, so resumed transfer failed. Client: 02:07:35 > PORT 192,168,1,119,225,47 02:07:35 < 200 Port command successful. 02:07:35 > REST 1582315785 02:07:35 < 500 'RE': command not understood. Server 02:07:35 admin [94.169.162.26] [180] < RE *T 1582315785 02:07:35 admin [94.169.162.26] [180] > 500 'RE': command not understood. This example was with the ICS FTP client and server, and I spent some time looking for a bug, before testing with FileZilla client and server and getting exactly the same error. (000006) 07/12/2010 12:51:19 - admin (217.146.115.81)> RE*T 12232905 (000006) 07/12/2010 12:51:19 - admin (217.146.115.81)> 500 Syntax error, command unrecognized. I solved the problem by using a second ADSL line that bypassed the Sonicwall (and disable virus checking on FTP downloads!). So sometimes FTP bugs are nothing to do with the FTP software. But firewalls can be useful, this Sonicwall will redirect all packets for one PC to another ethernet port so they can be captured, hardware sniffing. Angus -- To unsubscribe or change your settings for TWSocket mailing list please goto http://lists.elists.org/cgi-bin/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
