= Telnet =

'''`telnet(1)`''' is a text-based communication protocol and virtual terminal.

Historically, `telnet(1)` was used in a similar manner to modern [[Encryption/SSH|SSH]].

<<TableOfContents>>

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== Installation ==

Many [[Linux]] and [[BSD]] distributions meant for desktop use will come with `telnet(1)` installed. Otherwise, it is usually packaged either as `telnet` or bundled into a larger `inetutils` package.

''Do not install the telnet server.''

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== Usage ==



=== Open Street Map ===

{{{
telnet mapscii.me
}}}

See [[https://github.com/rastapasta/mapscii|here]] for details.



=== Star Wars ===

{{{
telnet towel.blinkenlights.nl
}}}



=== SMTP ===

To use `telnet(1)` for [[Email/SMTP|SMTP]], try running `telnet smtp.example.com 25`. This opens a REPL, which is annotated here with arrows denoting user input (`->`), server response (`<-`), and local client messages (`-`).

{{{
 -  Trying smtp.example.com...
 -  Connected smtp.example.com.
 -  Escape character is '^]'.
<-  220 smtphostname ESMTP Postfix
 -> ehlo smtphostname
<-  250-smtphostname
<-  250-PIPELINING
<-  250-SIZE 10240000
<-  250-VRFY
<-  250-ETRN
<-  250-ENHANCEDSTATUSCODES
<-  250-8BITMIME
<-  250-DSN
<-  250-SMTPUTF8
<-  250-CHUNKING
 -> mail from: me@example.com
<-  250 2.1.0 Ok
 -> rcpt to: you@example.com
<-  250 2.1.5 Ok
 -> data
<-  354 End data with <CR><LF>.<CR><LF>
 -> This is the body of an email.
 -> Exit this REPL by submitting a line that only contains a period.
 -> .
<-  250 2.0.0 Ok: queued as 0123456789ab
 -> quit
<-  221 2.0.0 Bye
 -  Connection closed by foreign host.
}}}

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== See also ==

[[https://man.archlinux.org/man/telnet.1|telnet(1)]]



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CategoryRicottone