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javaunixjsch

jsch-->Not able to connect from unix jump server to another unix servers using java


I am not able to connect secured server one unix server to another unix server.From putty by ssh i am able to connect easily but i am geeting below error when connet from jsch.

successful putty Steps->connect server1 in putty->on successful->Connect server2 using "ssh user@ip"

jsch steps-->

Connected session1-->one server connected //comment-->running command on server 1 to connect other server

Error:- Pseudo-terminal will not be allocated because stdin is not a terminal. Permission denied, please try again. Permission denied, please try again. Permission denied (publickey,password,keyboard-interactive). ksh: changeme: not found exit-status: 127

Jsch sample program-->

java.util.Properties config = new java.util.Properties();

        config.put("StrictHostKeyChecking", "no");
        JSch jsch = new JSch();
        jsch.setKnownHosts("C://known_hosts.txt");
         session=jsch.getSession(user1, server1, 22);
        session.setPassword(password1);
        session.setConfig(config);
        session.connect();
        System.out.println("Connected session1");

        String command ="ssh"+"  "+"user@ip;"+"password" ; 

         channel=session.openChannel("exec");   
        ((ChannelExec)channel).setCommand(command);
        channel.setInputStream(null);
        InputStream in=channel.getInputStream();
        ((ChannelExec)channel).setErrStream(System.err);   
        channel.connect();
        byte[] tmp=new byte[1024];
        while(true){
            while(in.available()>0){
                int i=in.read(tmp, 0, 1024);
                if(i<0)break;
                System.out.print("server 1"+new String(tmp, 0, i));
            }
            if(channel.isClosed()){
                System.out.println("exit-status: "+channel.getExitStatus());
                break;
            }
            try{Thread.sleep(1000);}catch(Exception ee){}
         channel.disconnect();
        session.disconnect();

Solution

  • I am adding important part of answer:-

          JSch jsch = new JSch();
          jsch.setKnownHosts("C:/My Program Files/eclipse/workspace/StatusTracker/known_hosts.txt");
         // jsch.setKnownHosts(knownHostLoc);
          //Jump server connection session started
          jumpServerSession = jsch.getSession(userid, jump server ip/hostname, 22);
          jumpServerSession.setPassword(jump server password);
          java.util.Properties config = new java.util.Properties();
          config.put("StrictHostKeyChecking", "no");
          jumpServerSession.setConfig(config);
          jumpServerSession.connect();
         System.out.println("The session has been established to "+jump server userid+"@"+jump server name);
    
            int assinged_port = jumpServerSession.setPortForwardingL(0, other server ip, 22);
            System.out.println("portforwarding: "+
                               "localhost:"+assinged_port+" -> "+other server ip+":"+22);
            //Main server connection session started
            targetServerSession =  jsch.getSession(fileBO.getServerUserId(), "127.0.0.1", assinged_port);
            targetServerSession.setHostKeyAlias(other server ip);
            targetServerSession.setPassword(other server password);
            java.util.Properties config1 = new java.util.Properties();
            config1.put("StrictHostKeyChecking", "no");
            targetServerSession.setConfig(config1);
            targetServerSession.connect();
    
    
            channel = targetServerSession.openChannel("sftp");
            channel = targetServerSession.openChannel("exec");
    
    //command want to execute on dest server
            ((ChannelExec)channel).setCommand("pwd"); 
    
              channel.setInputStream(null);
        InputStream in11=channel.getInputStream();
        ((ChannelExec)channel).setErrStream(System.err);   
        channel.connect();
        byte[] tmp1=new byte[1024];
        while(true){
            while(in11.available()>0){
                int i1=in11.read(tmp1, 0, 1024);
                if(i1<0)break;
                System.out.print(new String(tmp1, 0, i1));
            }
            if(channel.isClosed()){
                System.out.println("exit-status: "+channel.getExitStatus());
                break;
            }
            try{Thread.sleep(1000);}catch(Exception ee){}
        }
    
        } catch (final JSchException e) {
            LOGGER.error(e.getMessage());
        }