Hello, maybe someone could help me with my little FTP problem: When I'm downloading multiple files sometimes the transfer stops after Nth file (never in the middle of download). I think it's caused by some kind of timeout or something. The client is NATed, Here is a sample log of broken download sequence.
Code:
ftp> prompt y
Interactive mode off.
ftp> mget *
local: LM.pdf remote: LM.pdf
200 PORT command successful
150-Connecting to port 50854
150 247.7 kbytes to download
226-File successfully transferred
226 0.545 seconds (measured here), 454.33 Kbytes per second
253671 bytes received in 0.65 secs (383.4 kB/s)
local: LM_2.pdf remote: LM_2.pdf
200 PORT command successful
150-Connecting to port 56861
150 83.7 kbytes to download
226-File successfully transferred
226 0.079 seconds (measured here), 1.04 Mbytes per second
85748 bytes received in 0.18 secs (459.9 kB/s)
local: LM_3.pdf remote: LM_3.pdf
200 PORT command successful
150-Connecting to port 42299
150 6668.9 kbytes to download
226-File successfully transferred
226 15.095 seconds (measured here), 441.80 Kbytes per second
6829004 bytes received in 15.17 secs (439.6 kB/s)
local: LM_4.pdf remote: LM_4.pdf
200 PORT command successful
150-Connecting to port 33561
150 765.5 kbytes to download
226-File successfully transferred
226 2.839 seconds (measured here), 269.63 Kbytes per second
783827 bytes received in 2.86 secs (267.4 kB/s)
local: LM_automaty.pdf remote: LM_automaty.pdf
200 PORT command successful
150-Connecting to port 39246
150 401.2 kbytes to download
226-File successfully transferred
226 0.945 seconds (measured here), 424.62 Kbytes per second
410815 bytes received in 1.02 secs (393.3 kB/s)
local: Literatura.doc remote: Literatura.doc
200 PORT command successful
150-Connecting to port 50956
150 25.5 kbytes to download
226-File successfully transferred
226 0.000 seconds (measured here), 237.38 Mbytes per second
26112 bytes received in 0.08 secs (325.4 kB/s)
local: MPI_1_2.pdf remote: MPI_1_2.pdf
200 PORT command successful
---------> 500 Unknown command <--------------------------------- The problem starts here
local: analizator.pdf remote: analizator.pdf
500 Unknown command
ftp: bind: Address already in use
local: analizator_PL0.pdf remote: analizator_PL0.pdf
200 PORT command successful

421 Service not available, remote server has closed connection

receive aborted
waiting for remote to finish abort
Continue with mget? y
local: analizuj.pdf remote: analizuj.pdf
No control connection for command: No such file or directory
local: bledy.pdf remote: bledy.pdf
No control connection for command: No such file or directory
local: jezyki.pdf remote: jezyki.pdf
No control connection for command: No such file or directory
local: kompilator.pdf remote: kompilator.pdf
No control connection for command: No such file or directory
local: reagowanie_na_bledy.pdf remote: reagowanie_na_bledy.pdf
No control connection for command: No such file or directory
local: skladnia_PL0.pdf remote: skladnia_PL0.pdf
No control connection for command: No such file or directory
local: translator.pdf remote: translator.pdf
No control connection for command: No such file or directory
The broken download is marked with --------->. Also, I can't switch to passive mode because the connection hangs while entering the mode every time the data port is used (LIST, RETR, etc). I think the problem lies somewhere in the server's firewall configuration (iptables). I will be grateful if someone could point me out the possible cause of this strange behavior. Also I would be happy if someone could post the correct iptables configuration for FTP