Linux system Telnet service and linuxtelnet Service

Linux system Telnet service and linuxtelnet Service

Linux Telnet Service

Compared with ssh, telnet provides low security performance. However, you must enable this service when upgrading the ssh version or in other cases. The services provided by linux are executed by daemon, the daemon running in the background, and the telnet service is guarded by xinetd.

RedHat system:

Enable the telnet service:

1. Check whether telnet is installed.

2. Check whether the telnet service is enabled,

Command: chkconfig -- list | grep telnet

3. Enable the telnet Service

Method 1: vi/etc/xinetd. d/telnet

Vi/etc/xinetd. d/telnet

Service telnet

{

Disable = yes

Flags = REUSE

Socket_type = stream

Wait = no

User = root

Server =/usr/sbin/in. telnetd

Log_on_failure + = USERID

}

Add "#" to the front of the disable = yes line, or change it to "disable = no ".

4. Restart the xinetd daemon.

Because the telnet service is also protected by xinetd, after the telnet-server is installed, the xinetd must be restarted to start the telnet service.

[Root @ centos-64-min xinetd. d] # service xinetd restart

5. Disable the Firewall

1) takes effect after restart
Enable: chkconfig iptables on
Close: chkconfig iptables off

2) takes effect immediately and becomes invalid after restart
Enable: service iptables start
Disable: service iptables stop

6. If you want to Allow logon to telnet as root

Vi/etc/pam. d/login

Add # In front of auth required/lib/security/pam_securetty.so to comment out this line.

Disable telnet Service

(1) Method 1: Change distable = no to disable = yes in vi/etc/xinetd. d/telnet

Method 2: chkconfig telnet off if you need to set telent service not to start automatically at startup, use the command chkconfig -- del telnet

(2) Use the Command service xinetd restart or/etc/init. d/xinetd restart to make the change take effect.

Delete the telnet-server package: RPM-e telnet-server -- nodeps comment 23 port: vi/etc/service.