TELNET

                      # Telnet is used for remote login

SERVER		CLIENT
yum install telnet-*		No need telnet service’s
/etc/xinet.d/		telnet – is tool / utility / command
telnet  - edite & disable		telnet < server ip>
service xinetd reload		telnet 192.168.1.14
netstat -tulnp | grep -i 23  ---check port		no need to open 23 port
netstat –an | grep –i 23 ---check port		telnet 192.168.1.14 – used random port (Non-priviliged parts – above 1024 port used) 1 to 1023 ---priviliged port
netstat –vatnp | grep –I 23 ---check port
Check PID  /   Port
Total Ports no - 65535		1024 to 65535 is called non priviliged
by default root login disabled in telnet		telnet 192.168.1.14
telnet – check port / remote login		Login – Champu – User through login If you want root used su - root
telnet is not secure
ssh is used for remote login
ssh – secure socket host
Telnet VS ssh # Telnet – telnet transfer the ip packet in clear text mode # ssh – Secure socket host             ssh is transfer the ip packet in encryption  mode             [ Public license key + Private key ] --------------------------------------------------------------------------------------------------------------------- TELNET [root@Localhost ~]# yum install -y telnet-*  [root@Localhost ~]# rpm -qa | grep telnet  --- check Telnet Package  telnet-0.17-48.el6.x86_64 telnet-server-0.17-48.el6.x86_64 --------------------------------------------------------------------------------------------------------------------- [root@Localhost xinetd.d]# cd /etc/xinetd.d   -- telnet is base service of xinetd [root@Localhost xinetd.d]# ls chargen-dgram   daytime-stream  echo-dgram   swat           time-dgram chargen-stream  discard-dgram   echo-stream  tcpmux-server  time-stream daytime-dgram   discard-stream  rsync        telnet --------------------------------------------------------------------------------------------------------------------- [root@Localhost xinetd.d]# vim telnet   --- edit telnet file & disable telnet service service telnet {         flags                    = REUSE         socket_type         = stream         wait                     = no         user                     = root         server                  = /usr/sbin/in.telnetd         log_on_failure  += USERID         disable         = no     --------------------- type “no” for disable service } --------------------------------------------------------------------------------------------------------------------- [root@Localhost xinetd.d]# service xinetd reload   ----   reload xinetd service Reloading configuration:                                   [  OK  ] --------------------------------------------------------------------------------------------------------------------- [root@Localhost xinetd.d]#  netstat -tulnp | grep -i 23  -- check telnet port [root@Localhost xinetd.d]# netstat -an | grep -i 23 tcp        0      0 :::23                       :::*                        LISTEN      9876/xinetd     ---------------------------------------------------------------------------------------------------------------------