telnet

Windows CMD · Network · reference only

What it does

Telnet client: it opens an unencrypted text connection to a host and port. Today it is mostly used to check whether a port answers.

Syntax

telnet [opciones] [equipo [puerto]]

Options and parameters

• equipo

  Name or IP address of the host to connect to.

• puerto

  TCP port to connect to; 23 by default.

• -a

  Tries to log in automatically with the current user's name.

• -e carácter

  Escape character to return to the telnet prompt.

• -f fichero

  Saves the session log to a file.

• -l usuario

  User name to log in with.

• -t tipo

  Terminal type sent to the server.

Usage examples

• dism /online /Enable-Feature /FeatureName:TelnetClient

  Installs the Telnet client, which is not enabled by default (administrator console).

• telnet servidor 25

  Checks whether port 25 (mail) of the server answers.

• telnet 192.168.1.10 22

  If port 22 is open, the SSH server's greeting appears.

• telnet -f registro.txt servidor 23

  Connects saving the session to a file.

Notes and common mistakes

• Telnet encrypts nothing, not even passwords: use SSH to manage machines.
• To leave a session press Ctrl+] and type quit.

Related commands

• arp
• hostname
• ipconfig
• netstat
• nslookup
• pathping