LIST and RETR FTP commands fails if 6tunnel is used as ftp proxy

[raghu328568]

ftp.connect("fdf8:f535:82e4::52", 21)
'220 pyftpdlib 1.5.6 ready.'
ftp.login('ftp','password')
'230 Login successful.'
ftp.cwd('/RRHSIM6/logfiles/Full')
'250 "/RRHSIM6/logfiles/Full" is the current directory.'
ftp.retrlines('LIST')
Traceback (most recent call last):
File "", line 1, in
File "/usr/lib64/python2.7/ftplib.py", line 437, in retrlines
conn = self.transfercmd(cmd)
File "/usr/lib64/python2.7/ftplib.py", line 376, in transfercmd
return self.ntransfercmd(cmd, rest)[0]
File "/usr/lib64/python2.7/ftplib.py", line 335, in ntransfercmd
conn = socket.create_connection((host, port), self.timeout)
File "/usr/lib64/python2.7/socket.py", line 571, in create_connection
raise err
socket.error: [Errno 111] Connection refused
exit

proxy side:
[root@ruproxy-6 /]# ./6tunnel -6 -l fdf8:f535:82e4::52 21 -4 169.254.6.2 21 -L 20 -v
resolving 169.254.6.2
resolved to 169.254.6.2
resolving local address fdf8:f535:82e4::52
resolved to fdf8:f535:82e4::52
local: fdf8:f535:82e4::52,21; remote: 169.254.6.2,21; source: default
<4> connection from fdf8:f535:82e4:0:800::,51902 (no. 1)
<4> connected to 169.254.6.2,21

<4> connection closed
child process exited

[wojtekka]

6tunnel cannot act as an FTP proxy and at this moment there are no plans to support such mode of operation. FTP uses separate TCP connections for LIST and RETR and by default those connections come from server to the client, unless passive mode is used.