Sunday 18 September 2011

Configure linux telnet server step by step guide Example and Implementation

telnet server is used to login into another system. You can use the telnet command to log in remotely to another system on your network. The system can be on your local area network or available through an Internet connection. Telnet operates as if you were logging in to another system from a remote terminal. You will be asked for a login name and password. In effect, you are logging in to another account on another system. In fact, if you have an account on another system, you could use Telnet to log in to it.
You invoke the Telnet utility with the keyword telnet. If you know the name of the siteyou want to connect with, you can enter telnet and the name of the site on the Linuxcommand line.
CAUTION The original version of Telnet is noted for being very insecure. For secure connections over a network or the Internet, you should use the Secure Shell (SSH). We will cover SSH server in next article. SSH operate in the same way as the original but use authentication and encryption to secure the Telnet connection. Even so, it is advisable never to use Telnet to log in to your root account. That why by defaults root account is disable for root login.

Configure telnet server

In this example we will configure a telnet server and will invoke connectionfrom client side.
For this example we are using three systems one linux server one linux clients and one window clients. To complete these per quest of telnet server Follow this link
  • A linux server with ip address and hostname Server
  • A linux client with ip address and hostname Client1
  • A windows xp system with ip address and hostname Client2
  • Updated /etc/hosts file on both linux system
  • Running portmap and xinetd services
  • Firewall should be off on server
We have configured all these steps in our pervious article.
We suggest you to review that article before start configuration of telnet server. Once you have completed the necessary steps follow this guide.
Four rpm are required to configure telnet server. telnet, telnet-server, portmap, xinetd check them if not found then install
Now check telnet, portmap, xinetd service in system service it should be on

Select System service from list
Now restart xinetd and portmap service
service restart
To keep on these services after reboot on then via chkconfig command
After reboot verify their status. It must be in running condition
service status
Create a normal user named vinita

On Linux client

ping from telnet server and run telnet command and give user name and password
telnet form linux

On Window client

ping from telnet server and run telnet command
Give user name and password
user login

How to enable root login from telnet server

On linux server open file securetty
In the end of file add pts/0 to enable one telnet session for root.if you need to open more telnet session for root and add more pts/1 pts/2 and so on.
editing in securetty
Now restart xinetd and portmap service
service restart
Verfiy from window by login from root
root login telnet