linux telnet 安装配置

[root@Demo Packages]# rpm -ivh xinetd-2.3.14-33.el6.i686.rpm
warning: xinetd-2.3.14-33.el6.i686.rpm: Header V3 RSA/SHA256 Signature, key ID fd431d51: NOKEY
Preparing...                ########################################### [100%]
   1:xinetd                 ########################################### [100%]
[root@Demo cdrom]# rpm -ivh telnet-
telnet-0.17-47.el6.i686.rpm         telnet-server-0.17-47.el6.i686.rpm
[root@Demo cdrom]# rpm -ivh telnet-*
warning: telnet-0.17-47.el6.i686.rpm: Header V3 RSA/SHA256 Signature, key ID fd431d51: NOKEY
Preparing...                ########################################### [100%]
   1:telnet-server          ########################################### [ 50%]
   2:telnet                 ########################################### [100%]
[root@Demo Packages]# cd /etc/xinetd.d/
[root@Demo xinetd.d]# vi telnet
# 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
}
[root@Demo xinetd.d]# service xinetd restart
Stopping xinetd:                                           [FAILED]
Starting xinetd:                                           [  OK  ]
[root@Demo etc]# telnet 127.0.0.1
Trying 127.0.0.1...
Connected to 127.0.0.1.
Escape character is '^]'.
Red Hat Enterprise Linux Server release 6.2 (Santiago)
Kernel 2.6.32-220.el6.i686 on an i686
login: root
Password:
Login incorrect

login: admin
Password:
Last login: Sun Mar 17 10:05:35 from 192.168.1.100
[admin@Demo ~]$ su -
Password:
[root@Demo ~]#

使用root登录(默认root无法登陆)：
[root@Demo etc]# mv securetty securetty.bak
[root@Demo etc]# telnet 127.0.0.1
Trying 127.0.0.1...
Connected to 127.0.0.1.
Escape character is '^]'.
Red Hat Enterprise Linux Server release 6.2 (Santiago)
Kernel 2.6.32-220.el6.i686 on an i686
login: root
Password:
Last login: Mon Mar 18 00:52:51 from 172.1.1.1
[root@Demo ~]#

修改Telnet服务端的端口(默认为23)：
[root@Demo etc]# vi /etc/services
telnet          5023/tcp
telnet          5023/udp
[root@Demo etc]# telnet 127.0.0.1 5023
Trying 127.0.0.1...
Connected to 127.0.0.1.
Escape character is '^]'.
Red Hat Enterprise Linux Server release 6.2 (Santiago)
Kernel 2.6.32-220.el6.i686 on an i686
login: