[plug] Problem with gFTP

[Bret Busby]

On Thu, 3 Jul 2008, Bret Busby wrote:

> 
> On Thu, 3 Jul 2008, Keith Bawden wrote:
>
>> 
>>> When I did "man ftp", and looked at the options, and then used "ftp -v" to
>>> connect with one of my web sites, and then ran the command status, the
>>> response did not include indication of whether active or passive, file
>>> transfer was set.
>> 
>> During the initial connection did you see the word PASV. If so then
>> you are using passive mode. You can force the use of passive mode -
>> "ftp -p" . If it fails with -p then you know the problem is with using
>> passive mode.
>> 
>> 
>
> Thanks for that.
>
> I did it using the ftp command line utility, with the switches -pv and then 
> with -v, on another of my web sites, with the same ISP hosting the web site, 
> and the results clearly showed that the issue is with the passive mode.
>
> The ISP uses PLESK, and their "PLESK specialist" advised them that passive 
> mode is allowed, and that no such problem should be occurring. The "PLESK 
> specialist suggested that they check their "nat config", to ensure that the 
> problem does not lie there.
>
> I emailed the output of the "ftp -pv" and the "ftp -v" sessions to the ISP, 
> as it appears to me, that the problem lies at their end.
>
> Now, I wait and see...
>
> --
> Bret Busby
> Armadale
> West Australia
> ..............
>
>

Okay.

The ISP had no problem.

So, this appears to have got a bit more technical.

In looking at the three sessions below, some differences are notable.

The first session below, is me "ftp'ing" into one of my web sites at the 
ISP, using the switches -pv (passive mode and verbose mode).

"
~$ ftp -pv <domain name>
Connected to <domain name>.
220 ProFTPD 1.3.0 Server (ProFTPD) [203.113.228.30]
Name <domain name><username>
331 Password required for <user name>.
Password:
230 User <user name> logged in.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp> ls
227 Entering Passive Mode (203,113,228,30,135,177).
ftp: connect: Connection refused
ftp> bye
221 Goodbye.
"

The second session is me "ftp'ing" into the web site, using only verbose 
mode.

"
~$ ftp -v <domain name>
Connected to <domain name>.
220 ProFTPD 1.3.0 Server (ProFTPD) [203.113.228.30]
Name <domain name> <user name>
331 Password required for <user name>.
Password:
230 User <user name> logged in.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp> ls
200 PORT command successful
150 Opening ASCII mode data connection for file list
<directory listing>
226-Transfer complete.
226 Quotas off
ftp> bye
421 No Transfer Timeout (300 seconds): closing control connection.
"

The third session, is the ISP support person "ftp'ing into a web site 
there, using passive mode.

"
$ ftp -p <domian name>
Connected to <domain name>.
220 ProFTPD 1.3.0 Server (ProFTPD) [203.113.228.30]
Name <domain name><user name>
331 Password required for <user name>.
Password:
230 User <user name> logged in.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp> ls
229 Entering Extended Passive Mode (|||37379|)
150 Opening ASCII mode data connection for file list
<directory listing>
"

The primary difference between the three sessions, from what I see, is 
the line of response that immediately follows the ls command in each 
case, as it is different, especially the three digit number at the start 
of the linel, which, I assume, is some kind of message indicator.

For my unsuccessful attempt, I get
"227 Entering Passive Mode (203,113,228,30,135,177).".

For the ISP support person, the equivalent response is
"229 Entering Extended Passive Mode (|||37379|)".

Now, the questions are;

firstly, what is the difference between the 227 and the 229 codes, and,

the second question is, what is the difference between the "Passive 
Mode" and the "Extended Passive Mode", and,

the third question is, what is the significance of the difference 
between the numbers in the parentheses at the end of my unsuccessful 
response line, and, the number (and the vertical bars) in the 
parentheses at the end of the ISP's support person's successful response 
line?

Thanks in anticipation.

--
Bret Busby
Armadale
West Australia
..............

"So once you do know what the question actually is,
  you'll know what the answer means."
- Deep Thought,
   Chapter 28 of Book 1 of
   "The Hitchhiker's Guide to the Galaxy:
   A Trilogy In Four Parts",
   written by Douglas Adams,
   published by Pan Books, 1992

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