Turn Telnet on or off for Red Hat 5.2 on NPS

Answer

To enable or disable Telnet, log on to the server as the root user and display the file krb5-telnet.

[root@nps_server ~]# cd /etc/xinetd.d
[root@nps_server xinetd.d]# cat krb5-telnet 

# default: off
# description: The kerberized telnet server accepts normal telnet sessions, \
#              but can also use Kerberos 5 authentication.
service telnet
{
    disable    = yes
    flags        = REUSE
    socket_type    = stream        
    wait        = no
    user        = root
    server        = /usr/kerberos/sbin/telnetd
    log_on_failure    += USERID
}

[root@nps_server xinetd.d]# chkconfig krb5-telnet on
[root@nps_server xinetd.d]# service xinetd restart
Stopping xinetd:                                       [  OK  ]
Starting xinetd:                                       [  OK  ]

user@my-laptop:~$ telnet 192.168.100.10
Trying 192.168.100.10...
Connected to 192.168.100.10.
Escape character is '^]'.

    nps_server (Linux release 2.6.18-92.1.10.el5 #1 SMP Wed Jul 23 03:56:11 EDT 2008) (2)

login: nz
Password:
Last login: Mon May  4 15:05:21 from my-laptop.my-domain.com

     Current nps_server environment variables
==================================================

     HOME               = /export/home/nz
     USER               = nz

     NZ_DATABASE        = system
     MAX_SPU_CORES      = 3

     NUM_SPUS           =
     REAL_SPU           =
     SPU_REV            =
     ECHO_QUERY         =
     NO_MIRROR          =
     ABORT_ON_ERROR     =
     NZ_AUTOCREATE_DB   =

user@my-laptop:~$ telnet 192.168.100.10
Trying 192.168.100.10...
telnet: Unable to connect to remote host: Connection refused