Telnet is a network protocol that allows remote login over a network.It supports cross platform, that is a client sitting on a windows machine can access a telnet server configured on a linux machine.
It works on port number 23
In telnet data is transmitted in clear text over a network, that is it can be viewed by a third party over the network, however we can configure telnet to encrypt data before transmitting.
Telnet in RedHat and other rpm based Operating systems:
1. Install software
For Telnet Server we use “telnet-server” program.
Remember root access is required to install any package. We can switch to root account using following command in linux terminal
$su – root
We can install telnet using yum or rpm
(i) yum :
One can use yum to install directly from network
$yum install telnet-server
(ii) rpm :
If “telnet-server” package is available in local filesystem then we can install it directly from local system using rpm command.
$cd PATH_OF_DIRECTORY_CONTAINING_TELNET_SERVER_PACKAGE
$rpm -ivh telnet-server
2.Configuration
Configuration file for telnet is /etc/xinetd.d/telnet
Telnet service is disabled by default in its configuration file. We first have to enable it, by changing value of
disable = yes
to
disable = no
3. Start Service
Telnet service is managed by xinetd so we have to restart this service
$service xinetd start
Note:
In case any change is done in the configuration file, it will not be reflected immediately. So to update the change made, we have to restart the service
$service xinetd restart
Telnet Client
A client can access telnet server using command
$telnet SERVER_IP
or
$telnet SERVER_HOSTNAME
