From: Mike7739 <disposable7739-googlegroups@...>
Date: 2008-06-10T02:14:57+09:00
Subject: Re: Net::SSH 'channel_failure: 0' Error on Remote Host

Hi,
I figured out the answer to my original post. I used the PuTTy SSH
packets logging feature and was able to to make a script that mimicked
how PuTTY interacts with a Cisco Wireless LAN controller (WLC) when
logging in using SSH.

In a nutshell; you have to request an 'xterm' PTY (virtual terminal)
on the WLC, then request a new shell be created. Once I did that I
could see the WLC prompting for login credentials. After this is was
just a matter of sending strings as WLC commands over the channel.

Below is a basic script showing how I accomplished this:

require 'net/ssh'
#Open a new SSH connection
Net::SSH.start('1.1.1.1', 'username', :password =>
"password", :verbose => Logger::DEBUG) do |ssh|
    #Open a new channel
    ssh.open_channel do |channel|
        channel.request_pty(:term => "xterm") do |ch, success|
            if success
                puts "pty successfully obtained"
                ch.send_channel_request "shell" do |ch, success|
                    if success
                        puts "user shell started successfully"
                        ch.on_data do |ch, data|
                            puts "got stdout: #{data}"
                        end
                        ch.send_data("username\n")
                        ch.on_data do |ch, data|
                            puts "got stdout: #{data}"
                        end
                        ch.send_data("password\n")
                        ch.on_data do |ch, data|
                            puts "got stdout: #{data}"
                        end
                        ch.send_data("show ap summary\n")
                        ch.on_data do |ch, data|
                            puts "got stdout: #{data}"
                        end
                        ch.send_data("logout\nn\n")
                        ch.on_eof do |ch|
                            puts "remote end is done sending data"
                            ch.do_close
                        end
                    else
                        puts "could not start user shell"
                    end
                end
            else
                puts "could not obtain pty"
            end
        end
    end
end

Hope this can help someone.

Mike.