Net::FTP and 'Illegal PORT command'

[Bukowski]

Wise Monks,

I have been trying for a good hour now to figure out why this code is not working. I think it may be my ignorance of FTP coupled with my first use of Net::FTP.

The code:

#!/usr/bin/perl -w

use strict;
use Net::FTP;

my ($ftp, $destination, $username, $password, $filename, $path);

$destination="genome.ucsc.edu";
$username="anonymous";
$password="me\@there.com";
$path="/goldenPath/05apr2002/chromosomes/";
$filename="chr5.zip";

$ftp = Net::FTP->new($destination, Debug => 0) || die "Couldn't connec
+t! $!\n";
$ftp->login($username,$password) || die "Couldn't log in! $!\n";
$ftp->cwd($path) || die "couldn't cwd! $!\n";
$ftp->get($filename) || die "get($filename) failed: " . $ftp->code() .
+ ": " . $ftp->message();
$ftp->quit;

This dies with the error:

[dswan@ashtaroth GUP]$ perl ftp.pl
get(chr5.zip) failed: 500: Illegal PORT command.

I am assuming this has something to do with a failure to use the pasv/port options of Net::FTP - I have tried ftp->pasv() and ftp->port() (leaving blank, and specifying a port). Its not a firewall issue as I can happily use a command line client to make it work - and grab the file.

Yours, in bewilderment,

Bukowski - aka Dan ([e-mail])
"Coffee for the mind, Pizza for the body, Sushi for the soul" -Userfriendly

Title edit by tye

[amphiplex]

I would recommend turning up the Debug-Volume, this should give you and us valuable information.

---- amphiplex

[Bukowski]

OK with DEBUG set to 1 the relevant output is:

Net::FTP=GLOB(0x82456bc)<<< 220 ProFTPD 1.2.4 Server (ProFTPD Human Ge
+nome Project Server) [hgw3]
Net::FTP=GLOB(0x82456bc)>>> user anonymous
Net::FTP=GLOB(0x82456bc)<<< 331 Anonymous login ok, send your complete
+ email address as your password.
Net::FTP=GLOB(0x82456bc)>>> PASS ....
Net::FTP=GLOB(0x82456bc)<<< 230-
Net::FTP=GLOB(0x82456bc)<<<  
Net::FTP=GLOB(0x82456bc)<<<  This is the UCSC Genome Project ftp site.
Net::FTP=GLOB(0x82456bc)<<<        All transactions are logged.
Net::FTP=GLOB(0x82456bc)<<<  
Net::FTP=GLOB(0x82456bc)<<< 230 Anonymous access granted, restrictions
+ apply.
Net::FTP=GLOB(0x82456bc)>>> CWD /goldenPath/05apr2002/chromosomes/
Net::FTP=GLOB(0x82456bc)<<< 250-This directory contains the NCBI assem
+bled sequence for the 
Net::FTP=GLOB(0x82456bc)<<<  April 5, 2002 Genbank freeze in separate 
+files for each
Net::FTP=GLOB(0x82456bc)<<<  chromosome in a zipped Fasta format.
Net::FTP=GLOB(0x82456bc)<<< 250 CWD command successful.
Net::FTP=GLOB(0x82456bc)>>> PASV
Net::FTP=GLOB(0x82456bc)<<< 227 Entering Passive Mode (128,114,50,183,
+199,10).
Net::FTP=GLOB(0x82456bc)>>> PORT 192,168,1,125,172,80
Net::FTP=GLOB(0x82456bc)<<< 500 Illegal PORT command.
get(chr5.zip) failed: 500: Illegal PORT command.
Net::FTP=GLOB(0x82456bc)>>> QUIT
Net::FTP=GLOB(0x82456bc)<<< 221 Goodbye.

The same chunk from the SunOS machine:

Net::FTP=GLOB(0xfcd34)<<< 220 ProFTPD 1.2.4 Server (ProFTPD Human Geno
+me Project Server) [hgw5]
Net::FTP=GLOB(0xfcd34)>>> user anonymous
Net::FTP=GLOB(0xfcd34)<<< 331 Anonymous login ok, send your complete e
+mail address as your password.
Net::FTP=GLOB(0xfcd34)>>> PASS ....
Net::FTP=GLOB(0xfcd34)<<< 230-
Net::FTP=GLOB(0xfcd34)<<<
Net::FTP=GLOB(0xfcd34)<<<  This is the UCSC Genome Project ftp site.
Net::FTP=GLOB(0xfcd34)<<<        All transactions are logged.
Net::FTP=GLOB(0xfcd34)<<<
Net::FTP=GLOB(0xfcd34)<<< 230 Anonymous access granted, restrictions a
+pply.
Net::FTP=GLOB(0xfcd34)>>> CWD /goldenPath/05apr2002/chromosomes/
Net::FTP=GLOB(0xfcd34)<<< 250-This directory contains the NCBI assembl
+ed sequence for the
Net::FTP=GLOB(0xfcd34)<<<  April 5, 2002 Genbank freeze in separate fi
+les for each
Net::FTP=GLOB(0xfcd34)<<<  chromosome in a zipped Fasta format.
Net::FTP=GLOB(0xfcd34)<<< 250 CWD command successful.
Net::FTP=GLOB(0xfcd34)>>> PASV
Net::FTP=GLOB(0xfcd34)<<< 227 Entering Passive Mode (128,114,50,185,21
+6,226).
Net::FTP=GLOB(0xfcd34)>>> PASV
Net::FTP=GLOB(0xfcd34)<<< 227 Entering Passive Mode (128,114,50,185,21
+6,227).
Net::FTP=GLOB(0xfcd34)>>> RETR chr5.zip
Net::FTP=GLOB(0xfcd34)<<< 150 Opening ASCII mode data connection for c
+hr5.zip (59604544 bytes).

Two PASV commands?

Bukowski - aka Dan ([e-mail])
"Coffee for the mind, Pizza for the body, Sushi for the soul" -Userfriendly

[amphiplex]

I guess that setting

Passive=>1

when creating the ftp object should fix your problem. At least it did for me.

If it works, could someone explain why exactly ?

---- amphiplex

[valdez]

Net::FTP=GLOB(0x82456bc)>>> PORT 192,168,1,125,172,80

I think the error is here, you can't use a private address for the PORT command...

Ciao, Valerio

[gbarr]

You get the error because the PORT command is following a PASV command. They should not happen together.

You chopped off the top of the dubug output, what version of Net::FTP do you have installed ?

As someone else noticed you have a private IP, is the server on the other side of a firewall ?

If yes, you must use passive mode, as the remote server will not be able to connect back to you. But that is a different problem.

[Bukowski]

Now I'm even more confused. This code does not work on my RedHat 7.3 machine, but works fine on the SunOS 5.8 machine.

/me is off to investigate

Bukowski - aka Dan ([e-mail])
"Coffee for the mind, Pizza for the body, Sushi for the soul" -Userfriendly