FTP Upload Problems
Posted: 18 Mar 2010, 08:28
Hi,
I have a really strange upload problem. Files I do upload appear corrupted or set to zero length.
I tried to analyze the ftp traffic with wireshark. As an example I tried to upload a file with 2.931 bytes
repeatedly to a dreamhost ftp server.
Example of sucessfully upload:
-> FTP Request: STORE styles.css
-> FTP Data: 1260
-> FTP Data: 1260
<- FTP Response: 150 Opening BINARY mode data connection for styles.css
-> FTP Data: 411
<- FTP Response: 226 Transfer complete.
Example of erroneous upload:
-> FTP Request: STORE styles.css
<- FTP Response: 150 Opening BINARY mode data connection for styles.css
<- FTP Response: 226 Transfer complete.
The TCP flow before FTP Data shows:
OK:
69 6.055119 69.163.221.104 192.168.178.25 TCP 57995 > nfa [SYN, ACK] Seq=0 Ack=1 Win=5840 Len=0 MSS=1452
70 6.055148 192.168.178.25 69.163.221.104 TCP nfa > 57995 [ACK] Seq=1 Ack=1 Win=32768 Len=0
Wrong:
571 42.680589 69.163.221.104 192.168.178.25 TCP 58350 > b2n [SYN, ACK] Seq=0 Ack=1 Win=5840 Len=0 MSS=1452
572 42.680612 192.168.178.25 69.163.221.104 TCP b2n > 58350 [ACK] Seq=1 Ack=1 Win=32768 Len=0
573 42.680841 192.168.178.25 69.163.221.104 TCP b2n > 58350 [FIN, ACK] Seq=1 Ack=1 Win=32768 Len=0
Looks like the tcp connection is closed from serverside during store?
The problem is, anything looks fine from the ftp plugin view, but the file is zero.
Any help is appreciated. I can provide a complete wireshark trace of this.
BTW: Using keep alive options like "NOOP" does not change anything. Using Salamander Version 2.52. FTP Plugin Version 1.31
Thomas
I have a really strange upload problem. Files I do upload appear corrupted or set to zero length.
I tried to analyze the ftp traffic with wireshark. As an example I tried to upload a file with 2.931 bytes
repeatedly to a dreamhost ftp server.
Example of sucessfully upload:
-> FTP Request: STORE styles.css
-> FTP Data: 1260
-> FTP Data: 1260
<- FTP Response: 150 Opening BINARY mode data connection for styles.css
-> FTP Data: 411
<- FTP Response: 226 Transfer complete.
Example of erroneous upload:
-> FTP Request: STORE styles.css
<- FTP Response: 150 Opening BINARY mode data connection for styles.css
<- FTP Response: 226 Transfer complete.
The TCP flow before FTP Data shows:
OK:
69 6.055119 69.163.221.104 192.168.178.25 TCP 57995 > nfa [SYN, ACK] Seq=0 Ack=1 Win=5840 Len=0 MSS=1452
70 6.055148 192.168.178.25 69.163.221.104 TCP nfa > 57995 [ACK] Seq=1 Ack=1 Win=32768 Len=0
Wrong:
571 42.680589 69.163.221.104 192.168.178.25 TCP 58350 > b2n [SYN, ACK] Seq=0 Ack=1 Win=5840 Len=0 MSS=1452
572 42.680612 192.168.178.25 69.163.221.104 TCP b2n > 58350 [ACK] Seq=1 Ack=1 Win=32768 Len=0
573 42.680841 192.168.178.25 69.163.221.104 TCP b2n > 58350 [FIN, ACK] Seq=1 Ack=1 Win=32768 Len=0
Looks like the tcp connection is closed from serverside during store?
The problem is, anything looks fine from the ftp plugin view, but the file is zero.
Any help is appreciated. I can provide a complete wireshark trace of this.
BTW: Using keep alive options like "NOOP" does not change anything. Using Salamander Version 2.52. FTP Plugin Version 1.31
Thomas