使用SSH和Ruby连接到交换机

Question

I need to connect to a Cisco Switch with SSH and Ruby. The problem I'm having is that the authentication is different. With PuTTY I do like this: enter the 'login as' (any value, no consistence) then it asks for 'User Name' and 'Password', like this screen:

The option "SSH User Authentication by Password" in the switch config is disabled and enabling it is not an option.

My two last tries:

1 Using Net-SSH

Net::SSH.start(CISCO, USER) do |ssh|
    ssh.exec("echo hi")
end

Result: Net::SSH::AuthenticationFailed

2 Using Net-SSH-Telnet

tn = Net::SSH::Telnet::new("Host" => CISCO,
"Timeout" => 60,
"Prompt" => /^\login as:/ )

tn.cmd("\n") { |c| print c }
tn.cmd("#{USER}\n") { |c| print c }
tn.cmd("#{PASS}\n") { |c| print c }
tn.print("echo oi") { |c| print c }
tn.close

Result: Net::SSH::AuthenticationFailed

I guess I need to open a channel with the server and enter the login as, username and password as commands, but every time I get the AuthenticationFailed error. Any solution?

Answer 1

You have two choices:

Setup SSH keys : This way is ideal because it doesn't require a hard coded password. To do this you will need to generate the keys and edit your SSH config for password-less log in. Here is an example tutorial, HOWTO: set up ssh keys

Hardcoding your password : You can achieve this by adding the password for your user in your SSH connection

Hardcoding example:

Net::SSH.start(CISCO, USER, :password => PASSWORD) do |ssh|
  ssh.exec("echo hi")
end