[paramiko] migrate from Telnet to SSH

[James Bardin]

Chris Hallman wrote:
> Is channel the same a TCP connection?
>
> I've looked around can't find any example similar to what I need nor 
> can I
> figure out from the documentation what I need to do. I know that 
> client below
> instantiates the object/class. It opens the TCP connection. I just don't
> want to be creating thousands of TCP connections if I can get away with
> re-using the existing one. I've no idea yet how to do what I need. If you
> have any suggestions, I'd be grateful.
>
You're going to have to go beneath the SSHClient class, and use the 
building blocks yourself.
The pydocs are very good if you haven't seen them - 
http://www.lag.net/paramiko/docs/

This is what I would try next. You can do this interactively in the 
python shell, idle, ipython, etc.

######
import socket
import paramiko

sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect((''rtr3926', 22))

trans = paramiko.Transport(sock)
trans.auth_password('user', 'password')

# now open a channel that we're not going to use
dummy_chan = trans.open_session()

# here's the exec_command function from SSHClient
def exec_command(command):
    chan = trans.open_session()
    chan.exec_command(command)
    stdin = chan.makefile('wb')
    stdout = chan.makefile('rb')
    stderr = chan.makefile_stderr('rb')
    return stdin, stdout, stderr

stdin, stdout, stderr = exec_commnd('command')
########...

Hopefully the dummy_chan being left open will prevent the server from 
trying to close the connection.


-jim

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James Bardin - Systems Analyst / Administrator I
Boston University Department of Electrical and Computer Engineering
8 Saint Mary's St, Room 305, Boston, MA 02215
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