How to Automate telnet to connect UNIX from windows

if it is possible by telnet can you let me know how to do it using java

Thanks in advance

I dont have provision to buy a software and install it in my computer that is why I am asking how to do it in telnet

I am not using telnet to transfer data. I just want to execute CKSUM command in the remote UNIX system and bring the output to windows system

let me know if there is any way I can do it

Thanks

You can develop a telnet client in java..and execute your CKSUM sommand also...
There are various telnet client samples mostly you will found in C++, but  you can convert that easly for java..
You need RFC 0854 to understand how telnet client and server communicate, so , using client sockets in java you can create  your own customized telnet client which will only execute CKSUM command.

For telnet client samples and RFC:

www.codearchive.com/rate.php?rid=1391&go=0701

RFC:
http://www.faqs.org/rfcs/rfc854.html

They do have some example code in the Javadoc at:

http://javassh.org/download/source/de/mud/telnet/TelnetWrapper.html

but I think you had better be prepared for some frustration: I think it is easy to cause this program to hang, depending on the behavior of the remote host.

Hi,

You can download the Java Telnet Client on your machine and run it by using standard JDK. Here is the URL:

http://sourceforge.net/projects/jta/

Hope that helps,

Regards,

Warturtle

For the record, the JTA 2.5 that are available from the SourceForce web site and from javassh.org are the same code base.

And just to provide you with a complete example (where the target host name is a command line argument)

import de.mud.telnet.TelnetWrapper;

public class mytest {

static public void main(String args[]){

  TelnetWrapper telnet = new TelnetWrapper();
   try {
     telnet.connect(args[0], 23);
     telnet.login("amorrow", "mypass");
     telnet.setPrompt("user@host");
     telnet.waitfor("Terminal type?");
     telnet.send("dumb");
     System.out.println(telnet.send("pwd"));
   } catch(java.io.IOException e) {
     e.printStackTrace();
   }

}

}


I have not got this working yet, but it is close. Again, you will have to examine this tool to see how it tries to answers questions like "what does the login prompt look like?".

Also, I recommend that you use Ethereal  ( http://www.ethereal.com ) if you  .   It will display some of the telnet protocol that occurs.  You can compare the log of a successful telnet session (with any standard telnet client) and this software to see where it gets hung up.  This protocol tries to send stuff like what kinds of tty you have.  Also, I recommend that you set up the login account with no .cshrc or .profile files to avoid any extra output or things like a UNIX stty command that might mess you up.

One more follow-up.  I have not yet gotten the current version of JTA to work, but I did get jta25b to work for me.  What I found was that you have to know also know what they command prompt will be so that JTA can recognize when output has gone back to a wait state.  There is a version of jta25b at

http://www.netadmintools.com/files/jta25b-src.jar

and here is my current version of that program.  I left the host, "linux-int" to be a command line argument, but note how my prompt is specfic to that machine.

import de.mud.telnet.TelnetWrapper;
public class mytest {
 static public void main(String args[]){
  TelnetWrapper telnet = new TelnetWrapper();
   try {
     telnet.connect(args[0], 23);
     telnet.login("amorrow", "mypass");
     telnet.setPrompt("[amorrow@linux-int amorrow]$");
     System.out.println(telnet.send("pwd"));
   } catch(java.io.IOException e) {
     e.printStackTrace();
   }
 }
}

One other note: I noticed that JTA is hardcoded to expect the login prompts to be "login:" and "Password:".  This is true for almost all relevant versions
of UNIX and Linux.