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Today, I would like to share with you the relevant knowledge points about how Linux installs Telnet services. The content is detailed and the logic is clear. I believe most people still know too much about this, so share this article for your reference. I hope you can get something after reading this article. Let's take a look at it.

Telnet protocol is a member of TCP/IP protocol family, and it is the standard protocol and main way of Internet remote login service. It provides users with the ability to do remote host work on the local computer. Use the telnet program on the end user's computer and use it to connect to the server.

1. Install telnet1 and check whether the rpm package of telnet-server is installed [root@localhost ~] # rpm-qa telnet-server 1. If there is no output, it is not installed. For security reasons, telnet-server.rpm is not installed by default, while the client of telnet is standard. That is, the following software is installed by default.

2. If it is not installed, install telnet-server, otherwise ignore this step [root@localhost ~] # yum install telnet-server13, check whether the rpm package of telnet installs [root@localhost ~] # rpm-qa telnet telnet-0.17-47.el6_3.1.x86_64124, if not, install telnet, otherwise ignore this step [root@localhost ~] # yum install telnet1 2. Install xinetd service because the telnet service is also guarded by xinetd, so install telnet-server To start the telnet service, you must restart xinetd.

Xinetd or extended internet daemon,xinetd is a new generation of network daemon service program, also known as super Internet server. Often used to manage a variety of lightweight Internet services. The telnet service is managed through the xinetd service, so you need to install the xinetd service before installing the telnet service.

1. First check whether to install xinetd service # rpm-qa | grep xinetd12. If not, use the yum command to install # yum install-y xinetd package 13. After installation, you can start [root@locahost] # service xinetd restart 1. Third, note and error resolution 1. If xinetd is not installed, install it. 2. Change the configuration file / etc/xinetd.d/telnet. If this file does not exist, create this file. Change disable=yes to disable=no or comment out. That is, it should be changed as follows:

# 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=yes [comment out the disable=yes line before Or change yes to no]} 123456789101112133, log in to telnet using root. By default, root is not allowed to enter the Linux host as telnet. After the ordinary user telnet enters the system, you can use root users after switching to root users. If you have to log in using root, you can use to modify the securetty file.

Console vc/1 vc/2 vc/3 vc/4 vc/5 vc/6 vc/7 vc/8 vc/9 vc/10 vc/11 tty1 tty2 tty3 tty4 tty5 tty6 tty7 tty8 tty9 tty10 tty11 # below is added pts/1 pts/2 pts/3 pts/4 pts/5 pts/6 pts/7 pts/8 pts/9 pts/10 pts/11 123456789101112131415161718192021222324252627282930313233343536 add pts/1 … Pts/11 .

It is generally not recommended to use root users to log in to the system remotely through telnet, because telnet uses clear text in the process of data transmission, and if the data packet is intercepted, it will be easy to obtain the login password of root users; or it is recommended that ordinary users log in remotely through telnet, and then su to root, which is relatively secure. If it is necessary to use root users to connect remotely, it is recommended to use SSH.

4. Modify telnet port modification file / etc/services into the file

... Telnet 23/tcp telnet 23/udp... 1234 was modified to

Telnet 8902/tcp telnet 8902/udp 12 can restart the telnet service.

These are all the contents of the article "how to install Telnet Services in Linux". Thank you for reading! I believe you will gain a lot after reading this article. The editor will update different knowledge for you every day. If you want to learn more knowledge, please pay attention to the industry information channel.

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