The script below is trying to connect to a Cisco router, and is giving the error messages that follow. The same code when aimed at a linux server, changing only the host, user, password and command works fine. Any suggestions are appreciated.
#
use strict;
use Net::SSH::Perl;
use Net::SSH::Perl::Cipher;
my $port = "ssh";
my $host ="xxx.xx.x.x";
my $user = "xxxxxxxxx";
my $pass = "xxxxxx";
my $cmd = "show version";
my $ssh = Net::SSH::Perl->new($host,
debug => 1);
$ssh->login($user, $pass);
my($out, $err) = $ssh->cmd($cmd);

==============================================
root@ivan #./test.pl
Reading configuration data /root/.ssh/config
Reading configuration data /etc/ssh_config
Allocated local port 1023.
Connecting to XXX.XXX.XXX port 22
Remote protocol version 2.0, remote software version Cisco-1.25
Net::SSH::Perl Version 1.28, protocol version 2.0.
No compat match: Cisco-1.25.
Connection established.
Sent key-exchange init (KEXINIT), wait response.
Algorithms, c->s: 3des-cbc hmac-sha1 none
Algorithms, s->c: 3des-cbc hmac-sha1 none
Entering Diffie-Hellman Group 1 key exchange.
Sent DH public key, waiting for reply.
Received host key, type "ssh-rsa".
Host "172.20.6.3" is known and matches the host key.
Computing shared secret key.
Verifying server signature.
Waiting for NEWKEYS message.
Enabling incoming encryption/MAC/compression.
Send NEWKEYS, enable outgoing encryption/MAC/compression.
Sending request for user-authentication service.

Service accepted: ssh-userauth.
Trying empty user-authentication request.
Authentication methods that can continue: password.
Next method to try is password.
Trying password authentication.
Login completed, opening dummy shell channel.
channel 0: new [client-session]
Requesting channel_open for channel 0.
channel 0: open confirm rwindow 1024 rmax 4096
Got channel open confirmation, requesting shell.
Requesting service shell on channel 0.
channel 1: new [client-session]
Requesting channel_open for channel 1.
Entering interactive session.
Channel open failure: 1: reason 4:

Did either of you figure this out? I just came across this issue trying to use Net-SSH-Perl to maintain some routers, and am curious if you got anywhere with it.

As mentioned later in this thread, the problem in the routers is opening a second channel.

I had the same problem with ssh'ing to PIXes, and to get them working, I made the following changes to Net::SSH::Perl::SSH2:

sub login -> removed the code to open a "dummy channel"

sub client_loop -> change the check "last unless $oc > 1;" to "last unless $oc > 0;"

After making these changes, I am now able to open a Net::SSH::Perl connection to a PIX configured to only support ssh2. I'm not quite sure why the dummy channel is needed, perhaps servers disconnect once the channel count goes to 0.

While doing these changes gets Net::SSH::Perl to work with Routers Cisco, now I am unable to execute multiple commands.

For example, I execute:
($stdout, $stderr, $exit) = $ssh->cmd("show version");

And the output is:
MyMachine: channel 0: new [client-session]
MyMachine: Requesting channel_open for channel 0.
MyMachine: Entering interactive session.
MyMachine: Sending command: show ver
MyMachine: Requesting service exec on channel 0.
MyMachine: channel 0: open confirm rwindow 1024 rmax 4096
MyMachine: input_channel_request: rtype exit-status reply 0
MyMachine: channel 0: rcvd eof
MyMachine: channel 0: output open -> drain
MyMachine: channel 0: rcvd close
MyMachine: channel 0: input open -> closed
MyMachine: channel 0: close_read
MyMachine: channel 0: obuf empty
MyMachine: channel 0: output drain -> closed
MyMachine: channel 0: close_write
MyMachine: channel 0: send close
MyMachine: channel 0: full closed


Then I execute:
($stdout, $stderr, $exit) = $ssh->cmd("show run");


And the output is:
MyMachine: channel 1: new [client-session]
MyMachine: Requesting channel_open for channel 1.

...and the process stops.



What can I do to execute multiple commands, while preventing the "Channel open failure: 1: reason 4:" error??? Is it possible??
($stdout, $stderr, $exit) = $ssh->cmd("show version");
($stdout, $stderr, $exit) = $ssh->cmd("show run");


Thanks!

I am having the same problem executing multiple commands. Did anyone find a way to do this? If so, could you please let me know? thanks. I want to be able to do this too. ($stdout, $stderr, $exit) = $ssh->cmd("show version"); ($stdout, $stderr, $exit) = $ssh->cmd("show run"); ($stdout, $stderr, $exit) = $ssh->cmd("show snmp");

I am also facing this issue even after commenting out the suggested codes. Has anyone got this issue resolved. Please share your perl file or suggest the steps taken by you. Thanks

oh ok :) did you use Perl's expect or TCL ?? And also would like to know if you were connecting to Cisco Router by any chance... Because I see Cisco Boxes typically allow only one Channel to be open and that seems to be the problem I am facing..

Hi, Thank you so much for replying. Can you please explain me how you used Perl's Expect ? If you have some sample script, is it possible for you to share that with me @ udk@cisco.com Yes the box which I am trying to talk uses SSHv2 but then only one connection can be opened at a time but from the library implementation I could see multiple channel opens are done, so I assumed that could be the reason why I am getting errored out. If possible share your email id so that I can get the further assistance from you. Thanks In Advance for any kind of help provided.

Greeting,

were you ever able to send multiple commands to the router?

Let me know.