Net::SFTP::Recursive problem with ssh_args => [use

gman has asked for the wisdom of the Perl Monks concerning the following question:

Hello all,

I have been attempting to use Net::SFTP::Recursive, unfortunately the system I am connecting to appears to have a broken implementation of ssh. With debug:

host.fqdn.tld: Trying password authentication.
host.fqdn.tld: Login completed, opening dummy shell channel.
host.fqdn.tld: channel 0: new [client-session]
host.fqdn.tld: Requesting channel_open for channel 0.
host.fqdn.tld: channel 0: open confirm rwindow 32768 rmax 16384
host.fqdn.tld: channel 1: new [client-session]
host.fqdn.tld: Requesting channel_open for channel 1.
host.fqdn.tld: Channel open failure: 1: reason 4: Server supports one 
+session per SSH client
host.fqdn.tld: sftp: Sending SSH2_FXP_INIT
Connection closed at recurse_sftp.pl line 37
[download]

I did read this post 688247 but again, if I am reading the debug correctly it is still trying to open a second channel or am I reading the debug incorrectly?

Here is my code, pretty much right from the docs

use Net::SFTP::Recursive;
  my $host = 'x.x.x.x';

  my %cfg = (
                user=>'user',
                password=>'passwd',
                ssh_args => [ protocol => "2 1", use_pty => 0 ],
                debug => 'true' );

  my $sftp = Net::SFTP::Recursive->new($host,%cfg);
[download]

Thanks in advance!

Comment on Net::SFTP::Recursive problem with ssh_args => [use_pty => 0 ] Select or Download Code

Replies are listed 'Best First'.
Re: Net::SFTP::Recursive problem with ssh_args => [use_pty => 0 ] by salva (Canon) on Mar 02, 2011 at 20:44 UTC
Try using Net::SFTP::Foreign instead.	[reply]
Re^2: Net::SFTP::Recursive problem with ssh_args => [use_pty => 0 ] by gman (Friar) on Mar 02, 2011 at 21:00 UTC
Thank you, forgot about Net::SFTP::Foreign ++	[reply]
Re: Net::SFTP::Recursive problem with ssh_args => [use_pty => 0 ] by Khen1950fx (Canon) on Mar 03, 2011 at 02:33 UTC
I noticed a couple of errors. Looking at your debug output: `host.fqdn.tld: sftp: Sending SSH2_FXP_INIT` [download] That's telling you that Net::SFTP, which underlies Net::SFTP::Recursive, only supports SSH2 and not SSH1. So takeout the `protocol => '2 1'` because it isn't necessary. Second, I'd change `debug => 'true'` to `debug => 1` because it's easier to read. Then your script should start something like this: `#!/usr/bin/perl use strict; use warnings; use Net::SFTP::Recursive; use Data::Dumper; my $host = '127.0.0.1'; my %cfg = ( user => 'user', password => 'password', debug => 1, ); my $sftp = Net::SFTP::Recursive->new($host, %cfg);` [download] From what I can see, I think that your server expects SSH1, but it's not getting it:-).	[reply] [d/l] [select]
Re^2: Net::SFTP::Recursive problem with ssh_args => [use_pty => 0 ] by salva (Canon) on Mar 03, 2011 at 09:31 UTC
That's telling you that Net::SFTP, which underlies Net::SFTP::Recursive, only supports SSH2 and not SSH1 Not really! Net::SFTP implements version 3 of the protocol, that's the one supported by most servers regardless of its supported SSH protocol version. What happens is that the underlaying buggy Net::SSH::Perl is trying to open two channels inside the same SSH connection but the server only supports one channel per connection: `host.fqdn.tld: channel 0: new [client-session] host.fqdn.tld: Requesting channel_open for channel 0. host.fqdn.tld: channel 0: open confirm rwindow 32768 rmax 16384 host.fqdn.tld: channel 1: new [client-session] host.fqdn.tld: Requesting channel_open for channel 1. host.fqdn.tld: Channel open failure: 1: reason 4: Server supports one +session per SSH client` [download] Then, Net::SFTP does not check that the channel was successfully open, tries to send the INIT command anyway and fails. For comparison, opening a SFTP connection with OpenSSH: `$ ssh -v localhost -s sftp ... debug1: Authentication succeeded (publickey). debug1: channel 0: new [client-session] debug1: Requesting no-more-sessions@openssh.com debug1: Entering interactive session. debug1: Sending environment. debug1: Sending env LC_MESSAGES = en_AG.utf8 debug1: Sending env LANG = en_US.UTF-8 debug1: Sending subsystem: sftp` [download] It just opens a channel and uses it for SFTP.	[reply] [d/l] [select]