Telnet service is to provide a text-oriented communications and this service is used on internet/LAN using a virtual terminal connection. Telnet by default uses 23 port number. We will use telnet server installation and configurations on CentOS 6 / Red Hat family as this service is also applicable and works to fedora distribution environment.
IP Configuration ( My Server IP address is 172.16.41.82 )
Telnet Server Configuration
Open Terminal and login as root user.
Install Telnet server using yum.
[root@linuxpathfinder /]# yum install telnet telnet-server Setting up Install Process Resolving Dependencies --> Running transaction check ---> Package telnet.i686 1:0.17-47.el6_3.1 will be installed ---> Package telnet-server.i686 1:0.17-47.el6_3.1 will be installed --> Processing Dependency: xinetd for package: 1:telnet-server-0.17-47.el6_3.1.i686 --> Running transaction check ---> Package xinetd.i686 2:2.3.14-39.el6_4 will be installed --> Finished Dependency Resolution Dependencies Resolved ================================================================== Package Arch Version Repository Size ================================================================= Installing: telnet i686 1:0.17-47.el6_3.1 base 57 k telnet-server i686 1:0.17-47.el6_3.1 base 36 k Installing for dependencies: xinetd i686 2:2.3.14-39.el6_4 updates 122 k Transaction Summary ================================================================= Install 3 Package(s) Total download size: 215 k Installed size: 413 k Is this ok [y/N]: Press [y] to complete the installation. Installed: telnet.i686 1:0.17-47.el6_3.1 telnet-server.i686 1:0.17-47.el6_3.1 Dependency Installed: xinetd.i686 2:2.3.14-39.el6_4 Complete!
Need to configure telnet server, go to the directory /etc/xinetd.d to change configuration.
[root@linuxpathfinder /]# cd /etc/xinetd.d
Using vim editor to edit the telnet file.
[root@linuxpathfinder xinetd.d]# ls chargen-dgram daytime-dgram discard-dgram echo-dgram tcpmux-server time-dgram chargen-stream daytime-stream discard-stream echo-stream telnet time-stream
Change option ‘disable = yes’ to ‘disable = no’.
# default: on
# description: The telnet server serves telnet sessions; it uses \
# unencrypted username/password pairs for authentication.
service telnet
{
flags = REUSE
socket_type = stream
wait = no
user = root
server = /usr/sbin/in.telnetd
log_on_failure += USERID
disable = no
}
Restart the service after change in the file and permanently save the changes by using chkconfig option.
[root@linuxpathfinder xinetd.d]# service xinetd restart Stopping xinetd: [ OK ] Starting xinetd: [ OK ] [root@linuxpathfinder xinetd.d]# chkconfig xinetd on
Check out the firewall settings for further configuration:
[root@linuxpathfinder /]# setup
Enable the firewall settings and add telnet port 23 and Protocol is tcp.
Again restart the xinetd service after firewall settings.
[root@linuxpathfinder /]# service xinetd restart
Telnet Client Configuration
On the client end, you have to know the IP address of the remote server to access via telnet remotely. Remote communication with Telnet is insecure between server and client. For the secure communication use ssh service as explained already in previous tutorials.
Open Terminal and use the command telnet <server ip address>
Now put the username and password to access the remote system. (Login name : asifark)
Note : You cannot directly login as a super user in telnet.
[root@linux-server ~]# telnet 172.16.41.82 Trying 172.16.41.82... Connected to 172.16.41.82. Escape character is '^]'. CentOS release 6.4 (Final) Kernel 2.6.32-358.18.1.el6.i686 on an i686 login: asifark Password: Last login: Wed Sep 30 14:44:14 from 172.16.41.82 [asifark@linuxpathfinder ~]$ ls history_file.txt [asifark@linuxpathfinder ~]$ logout Connection closed by foreign host. [root@linux-server ~]#
i dont understand :/
ReplyDeletePortable Apps
Portable Apps