Before you install and use Telnet, you need to keep the following points in mind.
Telnet is the protocol used to telnet to a computer over a TCP/IP network. Once a connection is made to the remote computer, it becomes a virtual terminal and allows you to communicate with the remote computer.
Yum installs Telnet and telnet-server
[email protected] ~]# Yum install-y telnet telnet-server
Telnet is now installed on your server.
Edit File/etc/xinetd.d/telnet
[Email protected] ~]# vim/etc/xinetd.d/telnet
Set disable = no 650) this.width=650; "src=" Https://s3.51cto.com/wyfs02/M02/A4/62/wKioL1mpbj3SxxuqAAAo8e7KM04147.png "title=" Ww.png "width=" "height=" 239 "border=" 0 "hspace=" 0 "vspace=" 0 "style=" WIDTH:600PX;HEIGHT:239PX; "alt=" Wkiol1mpbj3sxxuqaaao8e7km04147.png "/>
Save and exit the file.
Description: We do not need to do this in Linux 7 , for reasons such as:
Yum installation telnet-server differences:
Linux6 Install Telnet-server When there is xinetd dependency package is installed, and Linux7 does not have xinetd dependency package is installed!
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Linux7
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turn on Telnet service
Span style= "FONT-SIZE:14PX;" > in Linux 6 system:
[[email protected] ~]# service xinetd start
[[email Protected] ~]# systemctl start telnet.socket
Boot from startup Telnet Service
In the Linux 6 system:
[[email protected] ~]# chkconfig telnet on
[Email protected] ~]# chkconfig xinetd on
In the LINUX7 system:
[Email protected] ~]# Systemctl enable Telnet.socket
To view the Telnet service health status
In the Linux 6 system:
[[Email protected] ~]# service xinetd status or [[email protected] ~]#/etc/init.d/xinetd status
In the LINUX7 system:
[[Email protected] ~]# service telnet.socket status or [[email protected] ~]# systemctl status Telnet.socket
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telnet default port is 23, view listening port
in Linux 6 system:
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Configuration of iptables and firewall:
Description
(1) If you do not use iptables and firewall you can turn them off, the command to close is as follows:
[Email protected] ~]# iptables-f
[[email protected] ~]#/etc/init.d/iptables stop
[Email protected] ~]# Systemctl stop Firewalld
[Email protected] ~]# systemctl disable FIREWALLD
(2) There is no longer iptables in Linux7, use Firewalld; the method of installing and using iptables in LINUX7 is as follows:
[email protected] ~]# Yum install-y iptables-services
To open the Iptables service:
[Email protected] ~]# systemctl start iptables
To view the Iptables service running status:
[Email protected] ~]# systemctl status iptables
Boot from iptables service:
[Email protected] ~]# Systemctl enable iptables
Using iptables:
[Email protected] ~]# Vim/etc/sysconfig/iptables
Add the following line "-A input-p tcp-m State--state NEW--dport 23-j ACCEPT"
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Description: Above is just demo under linux7 in Iptables installation and use, the actual work in linux7, we are using firewall!
(3) Turn on iptables and firewall, allowing Telnet to default port 23 through firewalls and routers.
In the Linux 6 system:
[Email protected] ~]# Vim/etc/sysconfig/iptables
Add the following line "-A input-p tcp-m State--state NEW--dport 23-j ACCEPT"650 "this.width=650; src= https://s5.51cto.co M/wyfs02/m02/a4/99/wkiol1muuluwqk-3aabaj_qxkho262.png "title=" Qq.png "alt=" wkiol1muuluwqk-3aabaj_qxkho262.png "/ >
Save exit! Restart the Iptables service.
[Email protected] ~]# service iptables restart
In the Linux 7 system:
[Email protected] ~]# firewall-cmd--permanent--add-port=23/tcp
[Email protected] ~]# Firewall-cmd--reload
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test
[[email protected] ~]# yum install-y telnet
Description: Install the Telnet package on the client
[[email protected] ~]# telnet 192.169.5.121
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Span style= "Font-family:arial, Helvetica, sans-serif;font-size:14px;" > finish!
This article is from the "Hand of the Paladin Control" blog, please make sure to keep this source http://wutengfei.blog.51cto.com/10942117/1962844