Difference between revisions of "Telnet"

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[[es:Telnet]]
 
[[es:Telnet]]
 
[[zh-CN:Telnet]]
 
[[zh-CN:Telnet]]
[[Wikipedia:Telnet|Telnet]] is the traditional protocol for making remote console connections over TCP. Telnet is '''not secure''' and is mainly used to connect to legacy equipment nowadays. For a secure alternative see [[SSH]].
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[[Wikipedia:Telnet|Telnet]] is the traditional protocol for making remote console connections over TCP. Telnet is '''not secure''' and is mainly used to connect to legacy equipment nowadays. Telnet traffic is easily sniffed for passwords and connections should never be made over any untrusted network including the Internet unless encrypted with [[SSH]] or tunneled though a VPN. For a secure alternative see [[SSH]].
  
Follow these instructions to configure an Arch Linux machine as a telnet server.
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Follow these instructions to configure an Arch Linux machine for telnet.
  
 
== Installation ==
 
== Installation ==
  
To use telnet only to connect to other machines, [[pacman|install]] {{Pkg|inetutils}}.
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To use the telnet client to connect to other machines, [[pacman|install]] {{Pkg|inetutils}}.
  
To configure a telnet server, install {{Pkg|xinetd}} as well.
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A telnet server can be configured with [[systemd]] sockets or xinetd. telnetd via systemd requires only the inetutils package. To configure a telnet server with xinetd, install {{Pkg|xinetd}} as well.
  
 
== Configuration ==
 
== Configuration ==
  
To allow telnet connections in xinetd, edit {{ic|/etc/xinetd.d/telnet}}, change {{ic|1=disable = yes}} to {{ic|1=disable = no}} and restart xinetd service.
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To enable telnet server connections in systemd, enable the systemd '''telnet.socket''' if the telnet server should be started on every boot and start the '''telnet.socket''' to test connectivity.
  
Enable [[systemd]] xinetd service if you wish to start it at boot time.
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$ systemctl enable telnet.socket
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$ systemctl start telnet.socket
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To enable telnet server connections in xinetd, edit {{ic|/etc/xinetd.d/telnet}}, change {{ic|1=disable = yes}} to {{ic|1=disable = no}} and restart the xinetd service.
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Enable systemd xinetd service if you wish to start it at boot time.
  
 
=== Testing the setup ===
 
=== Testing the setup ===
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  $ telnet localhost
 
  $ telnet localhost
  
Note that you can not login as root.
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Try a root login to see if your configuration permits it and the security implications that implies.

Revision as of 01:40, 24 May 2015

zh-CN:Telnet Telnet is the traditional protocol for making remote console connections over TCP. Telnet is not secure and is mainly used to connect to legacy equipment nowadays. Telnet traffic is easily sniffed for passwords and connections should never be made over any untrusted network including the Internet unless encrypted with SSH or tunneled though a VPN. For a secure alternative see SSH.

Follow these instructions to configure an Arch Linux machine for telnet.

Installation

To use the telnet client to connect to other machines, install inetutils.

A telnet server can be configured with systemd sockets or xinetd. telnetd via systemd requires only the inetutils package. To configure a telnet server with xinetd, install xinetd as well.

Configuration

To enable telnet server connections in systemd, enable the systemd telnet.socket if the telnet server should be started on every boot and start the telnet.socket to test connectivity.

$ systemctl enable telnet.socket
$ systemctl start telnet.socket

To enable telnet server connections in xinetd, edit /etc/xinetd.d/telnet, change disable = yes to disable = no and restart the xinetd service.

Enable systemd xinetd service if you wish to start it at boot time.

Testing the setup

Try opening a telnet connection to your server:

$ telnet localhost

Try a root login to see if your configuration permits it and the security implications that implies.