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How to exit telnet

I start telnet by telnet host port . How do I stop it in Windows? Shockingly, Ctrl + C doesn’t work.

4 Answers 4

It should have printed something along the lines of:

Since ^X is Ctrl X , try Ctrl ] for ^] .

You should then enter the telnet console, where you can enter quit to leave telnet.

Type quit to exit telnet in windows.

How to exit telnet

How to exit telnet

The ^] means ctrl + right bracket. As strange as that is, it works. You’ll be taken to the telnet prompt, where you can type quit or simply q .

On international keyboards the ] character is often not a single key, and needs to be replaced with some other key. The correct key is typically the key to the right of P or the next key after that.

Here’s a list based on comments below:

  • Finnish, Swedish, Norwegian, Danish: ctrl + å
  • French: ctrl + 6
  • German, Turkish: ctrl + ü
  • Swiss: ctrl + ¨
  • Hungarian: ctrl + 5 or ctrl + ú
  • Portuguese: ctrl + ´
  • Dutch, Belgian: ctrl + $
  • Canadian French: ctrl + ç
  • Italian: ctrl + +

Quote from @jtbandes answer here: https://superuser.com/a/427/192525 All creds to him.

PS: Answer reproduced here for your convenience, since google took me to this question first, and none of the other answers here was sufficient for my case. The question How to send the escape character on OS X terminal? could be seen as a duplicate (more generic version) of this question, since the OP’s problems are basically the same.

How do I close a telnet session/window?

This article assumes that you’ve started a telnet connection through the Windows command prompt (you can do so by typing: “telnet address port”).

Answer: To end your current telnet session you must reach the telnet prompt and type quit.

Here are the steps for doing so:

  1. Open the telnet prompt by holding down the ‘Ctrl’ key and push the ‘]’ key. (prompt: Microsoft Telnet>)
  2. Type quit.
  3. Push the ‘Enter’ key.

You can change this default telnet prompt key by starting telnet like this: telnet –e p 192.168.1.81(this will change the telnet prompt key to lowercase ‘p’)

12 Responses to “How to end a telnet session (Windows, Linux, Mac)”

Nik says: Hey, Thanks a lot. I had opened a telnet connection and had no idea how to close it until I came across this! By the way, I am logged in Ubuntu. So the steps you have mentioned for windows work for linux as well.

January 1, 2010 at 2:05 am (Edit)

Cpascu says: Good to know, changed the title accordingly 🙂

January 12, 2010 at 11:36 am (Edit)

Thomas says: Hi, great post, could you please mention, that this also work with other key mappings? e.g. on german keyboards the ‘]’ is a composed key, but the same key position as on english keyboards works: use [Ctrl] + [+] there. Regards, Thomas

January 28, 2010 at 12:20 am (Edit)

M L Sreekanth says: THANKS ALOT…… Every time i used to close the window or putty to come out of the session.

May 7, 2010 at 2:59 am (Edit)

Jimmy says: This is HELPFUL! I’m on mac OS X 10.6.6 and the same key commands work to get the prompt so that you can properly close the window. You could add Mac to the title of the page, too! Thanks!

February 17, 2011 at 5:28 am (Edit)

Neetish Jehra says : Thanks very handy!

May 31, 2011 at 3:26 pm (Edit)

Omo Olorun says: Nic eone, thanks.

July 3, 2011 at 11:46 pm (Edit)

Sameet says: So I am curious as to What Ctrl+C does not do that this does or are they the same. What I am trying to get at is does Ctrl+C leave open/lingering connections

November 26, 2013 at 8:48 am (Edit)

Uro says: For non English keyboard you can press and hold Alt key then enter 29 on num keypad. This will send ‘^]’ control character to the terminal according to the ASCII table.

December 17, 2013 at 3:56 am (Edit)

Shilpa says: How to kill a telnet session, when the telnet console window is closed mistakenly.

August 27, 2014 at 3:47 am (Edit)

Nene says: Thanks a lot, it helped me a lot.

September 30, 2014 at 7:25 am (Edit)

MJ says: in linux, I type echo|telnet server_ip tcp_port this will help me not to enter the escape character but will end the telnet session be it good or bad. What is similar option in windows?

February 17, 2016 at 4:00 am (Edit)

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How to close telnet terminal in Linux and Windows (quit, exit not working)? Example

The telnet is one of the most useful Linux networking commands, which is used to check if a server is listening on a particular port and it’s whether up and running or not, but it’s a little bit tricky to use, especially, if you are not using it on daily basis. Though I have used telnet before, when I use it after a long time, I actually forgot how to close the telnet terminal and how to get out of it. I tried every possible Linux commands I can think of which is used to close, cancel a command, or exit from VIM editor in UNIX, like Ctrl + C, quit, exit, q! and even the escape character ‘^]’, only to realize that nothing is working. It may sound silly that an experienced developer cannot even come out of a telnet terminal but this is a true story.

What I have noticed in general is that, even though we learn new things when our experience grows, we actually forget something equally important as well, particularly if we don’t use that thing or command on daily basis.

Our mind is trained to keep only important stuff in memory, if a particular thing, particular knowledge or concept is not used for a long time and doesn’t find very important something like life or death, it slowly offloads it. The trick here is to revise and reuse it once in a while.

I finally managed to come out from the telnet command prompt after a bit of struggle, and trial and error but I was surprised how difficult it can be to use one of the top 10 networking commands in UNIX.

So, not to forget again and to help anyone who is stuck in the same situation, I decided to share my thoughts in this post.

Let’s see the exact command to close the telnet terminal in Linux and Windows 10. Though, keep referring a good UNIX command course like Linux Command Line Basics not to forget important commands like telnet.

How to close telnet terminal in Linux and Windows

Before looking at how to come out of the telnet command prompt, let’s first look at how not paying enough attention and thinking that every command will work same way can confuse you easily.

You can see below that I had tried everything I could to come out of telnet windows but nothing worked, but had I paid attention to the telnet message that ” Escape character is ‘^]'” , I would have probably been able to come out of telnet terminal earlier.

The trick here is you need to first type escape character e.g. ‘^]’ which is ‘Ctrl + ]’ and then type quit to close the telnet terminal in Linux or any UNIX system.

I expect the same command will work on Windows and Mac also as telnet is ubiquitous and you will find telnet command in a host of the operating system including the big three e.g. Linux, Windows, and Mac. See these Best Websites to learn Linux for FREE to learn more about basic commands like telnet command in UNIX/Linux.

How to exit telnet

Here are the exact steps to end a telnet session in Linux and Windows :

1. Open the telnet prompt by holding down the ‘Ctrl’ key and push the ‘]’ key. (prompt: Microsoft Telnet>)
2. Type quit.
3. Push the ‘Enter’ key.

The telnet is an extremely useful command and is used a lot in client-server applications e.g. you can use this to solve connection refused error in Java, which is mostly due to incorrect client-server communication.

In the electronic trading and FIX protocol world, telnet is a great tool to diagnose FIX session connection issues as described in this article.

You can even use telnet to check if your own HTTP server is running or not as I have discussed when talked about building HTTP server in Java, here.

That’s all about how to exit from the telnet terminal on Windows or Linux. As I told its one of the must-know networking commands and is available on almost all operating system. When you don’t use it regularly sometimes it becomes tricky to operate as shown in this article, but just remember that you need to first type escape character to actually type command in telnet, while it is connected to a server.

Other Linux command tutorials for Java Programmers

  • 10 examples of lsof commands in UNIX (examples)
  • 10 basic networking commands in Linux (list)
  • How to send an HTTP request from the Linux command prompt? (command)
  • 10 examples of chmod command in UNIX (examples)
  • 10 examples of xargs command in UNIX? (examples)
  • 10 UNIX and Linux command-based questions from Interviews (list)
  • 10 Examples of curl command in Linux (examples)
  • 5 Courses to learn Bash Scripting in Linux (Courses)
  • How to find the largest file and directory in Linux (tutorial)
  • How to find which process is using a port in Linux (tutorial)
  • 10 Tips to work fast in Linux (tips)
  • 5 Free Courses to Learn Linux Online (courses)
  • Practical Guide to Linux Commands (book)

Thanks for reading this article so far. If you like these Linux command tutorial then please share with your friends and colleagues. If you have any questions or feedback then please dro a note.

on Windows XP/server 2003

When telnet some remote host on a specified port, after connection established, sometimes press ctrl+] doesn’t quit. Is there any command can quit instead of just close the command line window? Thanks.

EDIT: But sometimes even type ctrl + ] , telnet command line doesn’t show up, still stuck at the blank screen.

10 Answers 10

ctrl+] is an escape sequence that puts telnet into command mode, it doesn’t terminate the session. If you type close after hitting ctrl+] , that will “close” the telnet session.

on German keyboards the following keystrokes will help

You can use the ‘quit’ command, or abbreviate it to just ‘q’ if you like.

The solution worked for me is

Then after when you will be in telnet invite type

then enter to exit from telnet and return to your DOS invite

I’m not terribly familiar with Windows telnet, but local behavior on non-Windows boxes using telnet is a combination of the telnet state and that of the terminal or enclosing window and shell. (If your remote connection has changed the echo mode, font color, interrupt status, and etc, killing telnet has no effect on that local status.)

Does Windows have similar local status? (I assume so, or most text editors and many other programs wouldn’t work in telnet windows.)

For Unix, the typical sequence was Ctrl ] → quit → return → stty sane → return to get local control and tty sanity. What’s the Windows equivalent of “tty sane”?

ctrl+] will take you to command mode if the telnet client is already connected; from there you can type (q)uit to exit.

If it’s connecting, however (or failing to connect. ), then there is no way to interrupt the process until it times out.

Standard way of disconnecting the line in most applications is

+ . , keep in mind, that often this has to be typed in blindly, so press enter a couple of times: Enter +

This is also the standard way of closing the connection on an SSH session, that became unresponsive.

On a French keyboard I have to use ctrl+$

Then ‘quit’ from the resulting telnet prompt.

maybe with ctrl + d ?

At least in my Linux system, the only way to exit from a telnet session is by using the following keys (pressing the 3 keys together: Ctrl, AltGr,+ and then the following prompt appears: telnet> Now press the key q and the telnet session will be terminated.

Not the answer you’re looking for? Browse other questions tagged windows telnet or ask your own question.

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Mattias Geniar, December 12, 2019

Follow me on Twitter as @mattiasgeniar

We’ve all been there, right? You debug something, you try telnet to see if a port is open, and now you’re stuck in a telnet session.

And the answer seems so obvious. It’s staring us right in the face!

Escape character is ‘^]’.

Good! There’s an escape sequence. This is like one of those text based adventure games. I can beat this!

So you carefully copy/paste the ^] text shown at the top. A caret and then a closing square bracket. That wasn’t too hard. But why isn’t this working?

Ah it turns out that ^ sign is a symbol. It represents the CTRL button on the keyboard. It’s a key combination that I have to press.

This is where the text adventure turns the difficulty level way up. My keyboard doesn’t have a ] sign on it. 😱

How to exit telnet

It’s got all sorts of obscure markers though. What’s that § thing below the number 6? And how often do you need a ù ? Clearly one of those should’ve been a ] button!

But have no fear, there are hidden key combo’s. On Mac I can type OPTION + SHIFT + ° and that produces ] .

So the magic incantation to exit a telnet session has to be CMD + OPTION + SHIFT + ° . That’s four (4) keys at the same time. Good thing we’ve been given 5 fingers! Something tells me the end-boss in this game is going to require 5 key combo’s.

It’s a Unix system. I know this.

I bet that Jurassic Park girl knows how to quit a telnet session. I’ve only been managing Linux servers for 15 years, what the heck do I know?

OK Mattias, think. What are you missing in this game? You’re playing it in Belgium, but it was probably designed by someone from the US. Or Sweden.

What do those keyboards look like?

How to exit telnet

Aha, they do have a dedicated key for the ] symbol. Spoiled little brats.

On to the text adventure: the key I’m looking for appears to be 2 keys to the right of P key. Good, let’s try!

I’ve won! I’ve beaten the end game! 🎉

Turns out, the magic key combination to exit a telnet session is CMD + that one weird key 2 positions to the right of the P . Unless you’re on a German keyboard. Then it’s one position to the right of P, not two. Because obviously.

★☆☆☆☆ — Lousy text adventure game, does not work.

The cheatcodes to beat the exit-a-telnet-session game

Most text adventure games have cheatcodes. I’ll provide the same for the how to exit a telnet session text adventure. If you’re stuck and want to quit, but you don’t have a ] on your keyboard, try one of those.

  • Dutch, Belgian: ctrl + $
  • French: ctrl + 6
  • Finnish, Swedish, Norwegian, Danish: ctrl + å
  • Swiss: ctrl + ¨
  • German: ctrl + ü
  • Hungarian: ctrl + 5
  • Portuguese: ctrl + ´
  • Canadian French: ctrl + ç

Or get a keyboard with a dedicated button.

Create your own text adventure telnet game!

You can create your own levels of the telnet game. Telnet allows you to set a custom escape character with the -e flag.

This would be especially diabolical if you were to, say, create a system-wide alias for telnet on all your servers to mess with your coworkers.

With the -e parameter you can give it a sane escape value. Or you could try to make the combo even worse with an alias and reverse the square bracket.

I’m not saying I would do that.

Playing the text adventure game

If you want to play the text adventure, telnet to a known nameserver. They respond to port 53 via UDP and TCP (for large DNS replies). Depending on the nameserver version they’re running, they don’t immediately close the connection if you send it garbage inputs.

Recently, some users of CentOS reported that it was a problem of Windows firewall after telnet connection, but after telnet command connection was successful, they found that they could not retreat. What should we do? The following edition will introduce the solution of Telnet exit failure under CentOS. Let’s go and have a look.

How to exit from telnet of Linux

1.ctrl+] quit

Telnet is often used to test whether the port is open properly.

But there is a problem that we may encounter. We can’t exit after telnet enters a certain port. We have to turn off this DOS (or other) window and open a new one in order to continue testing. Here’s a way to press Ctrl +] to exit to the normal telnet interface

Welcome to Microsoft Telnet Client

Escape Character is ‘CTRL+]’

Then enter quit to exit completely.

2. Simple usage of Telnet:

First, build a Telnet server. Previously, in order to make the machine faster, some unused services were shut down.

Open your Telnet in the “Control Panel” – “Management” – “Service” and enter the user name and password you want the client to enter in the login tab. It’s OK. The Telnet server is set up.

Test it on your own machine. On the command line, you can enter Telnet’s native IP. Then you can enter the user name and password step by step.

If you want to quit, go through “Ctrl+]” and quit later.

3. The second method of running telnet program:

Enter command: telnet

At this point, the program runs, but it does not connect (because the host is not specified)

Then the screen shows telnet >

This is the prompt for telnet, which indicates that the telnet program is running and waiting for the user to enter a command using telnet. If you want to connect to a remote host, you use the open command, that is, to enter the command open, and attach the host’s network address, such as

telnet> open dns.hunu.edu.cn

The connection effect is exactly the same as that of the first method.

4. How does telnet log on to a system?

A: The original way of Telnet login can be realized on the command line, such as entering telnet www.lqqm.net on the windows command line to login to the site and entering telnet www.yjrg.net to login to BBS at the same time. It is recommended to download and use special telnet login tools, such as cterm, sterm, fterm, personal three have been used for a period of time, and feel that Cterm is the best way to login; and other professional telnet login is the best way to login. Tools also include security CRT and so on. It should be noted that the telnet command uses UDP protocol and SSH uses TCP protocol. The essential difference between them determines that telnet logs in faster than SSH, but SSH logs in safer than telnet logon (passwords are not usually deciphered). The relationship between them is similar to that between FTP and tftp.

Telnet idle timeout automatic exit

Setting telnet connection idle for more than a certain time automatically exits the current session

Set the parameter TMOUT in seconds (s)

TMOUT = 21600, telnet connection will automatically disconnect after idle for 6 hours.

Global TMOUT can be set in / etc / profile or TMOUT can be set in the. profile of the user’s home directory.

When idleness reaches the set value, the screen displays

timed out waiting for input: auto-logout

And disconnect the current telnet connection

View the TMOUT value of the current session

This feature is disabled when TMOUT is not set or TMOUT = 0 is set.

What about telnet exit failure under CentOS

Can’t go out! Ctrl + c, Ctrl + z, ESC, q, quit, exit, can’t;

Note the message output after telnet connection is successful:

Escape character is ‘^]’。

The method is right at last.

Commands may be abbreviated. Commands are:

close close current connection

logout forcibly logout remote user and close the connection

display display operating parameters

mode try to enter line or character mode (‘mode ?’ for more)

open connect to a site

quit exit telnet

send transmit special characters (‘send ?’ for more)

set set operating parameters (‘set ?’ for more)

unset unset operating parameters (‘unset ?’ for more)

status print status information

toggle toggle operating parameters (‘toggle ?’ for more)

slc change state of special charaters (‘slc ?’ for more)

z suspend telnet

! invoke a subshell

environ change environment variables (‘environ ?’ for more)

? print help information

Enter a question mark and return to see the help.

Enter close or quit and return to telnet.

The above content is the solution to the failure of Telnet exit under CentOS brought to you by Xiaobian. When you encounter such problems in the operation process, you can refer to the methods described above to solve them. Hope this document can help you!

I’m running telnet command on a host for a given port (which is open), it returns 0 (success).

For trying telnet manually, I type the following command, then I press control+bracket i.e. ^] , then press Enter key, then I get to telnet> prompt, where if I type close or quit , it comes back to the $ prompt and seeing exit status of last command shows 0 for (success) as port 2878 is open (as per the telnet command’s output).

Now, I wanted to run the same operation without any human intervention i.e. I don’t want to manually give ^] and press Enter key to come to the telnet> prompt, then enter close (or quit ) telnet command to finally come back to the $ prompt.

For this, I tried using echo -e command’s option and giving ^] , \n (for new line character i.e. Enter key) and close command (for telnet> prompt so that I come back to $ prompt). Doing this, kind of worked as expected but for the exit status of last command echo $? , I’m getting 1 (instead of 0). Why?

or tried the here-doc method as well, but not sure why it’s returning 1 (as exit code) for a valid port which is open.

How can I automatically exit from telnet if the port is open and get 0 as exit code? If there’s a way to capture the output of the previous command, may be I can grep the ‘Connection closed by foreign host.‘ string to mark it successful (0).

In a similar manner to ftp allowing a user to transfer files across the Internet, telnet allows users to log onto and work on remote machines as if they were sitting at one of its terminals. How usable this remote login is depends on how well the machines are connected and how well your terminal is recognized by the foreign machine. As the distance between machines increases, and the number of networks that must be interconnected (the number of hops), the response time between a user entering a character and the remote machine responding to it increases. You can measure this round trip time with the ping command as discussed in Chapter 2. If the ping times are greater than 500 milliseconds, the remote machine will seem unresponsive and you will find it hard to be productive. Slow connections are common when using machines at far-removed different sites. If you are of the patient type, your telnet session will be usable but editing may be difficult.

Telnet has very few options and is simple to use. Like ftp you just give the name of the machine you want to connect to as an option:

Once we get the login: prompt, the login is the same as from any other terminal. Telnet will automatically try to set your TERM variable for you so the foreign machine knows your terminal type, but nevertheless, you may have to correct it if the remote machine does not know about the name it was sent as your terminal type.

To end the telnet session, log off the remote machine. If the connection is hung, that is, you have stopped getting a response, you will not be able to log off and so you should use the telnet escape character to get a telnet prompt and then quit the telnet session. The telnet escape character may be either ^] or ^t. You will also get the telnet prompt if telnet does not recognize the remote hostname you use. In this case you are not connected to the foreign machine but are just running telnet. You can quit telnet or tell telnet to open some other machine.

Home » SysAdmin » How To Use Telnet On Windows

Telnet (teletype network) is a network protocol for two-way text-based communication through a CLI, allowing remote access. Telnet is vulnerable to cybersecurity attacks because it lacks encryption methods compared to the more modern SSH. However, it is still helpful for tasks that do not involve transmitting sensitive information.

This article teaches you what Telnet is as well as how to use Telnet on Windows to test for open ports.

How to exit telnet

  • Windows OS with administrator privileges
  • Access to the command prompt
  • An address and port to test

What is Telnet?

Telnet is a client-server protocol predating the TCP protocol. The network protocol allows a user to log into another computer within the same network through a TCP/IP connection.

A client machine running the Telnet client connects to a CLI on a remote device, most commonly a dedicated platform. Telnet is lightweight and fast, making it the preferred option in some use cases:

  • Initial network hardware configuration.
  • Remote access to trusted internal networks.
  • Testing for open or used ports.
  • Troubleshooting mail and web servers.
  • Checking port forwarding.

How Does Telnet Work?

The Telnet protocol creates a communication path through a virtual terminal connection. The data distributes in-band with Telnet control information over the transmission control protocol (TCP).

Unlike other TCP/IP protocols, Telnet provides a log-in screen and allows logging in as the remote device’s actual user when establishing a connection on port 23. This type of access grants direct control with all the same privileges as the owner of the credentials.

Telnet comes with a command accessible from the command line in Windows. The telnet command also exists for macOS and Linux operating systems.

How to Enable Telnet on Windows 10?

In Windows systems, Telnet is disabled by default. To check if Telnet is already activated, open your command line, and run telnet :

If the command prompt does not recognize the command, there are two possible ways to enable the Telnet client in Windows.

Option 1: Enable Telnet using GUI

To activate the Telnet command using the GUI:

1. Open the Programs and Features options in Control Panel:

How to exit telnet

2. Click the Turn Windows features on or off setting:

How to exit telnet

3. Locate the Telnet Client option on the list, select it and click OK to install the feature:

How to exit telnet

4. When Windows completes the requested change, click Close.

5. Open the command prompt and run telnet to open the Microsoft Telnet Client:

6. Run quit to exit the Telnet client.

Option 2: Enable Telnet Using Command Prompt

To activate the Telnet client from the command prompt:

1. In the command prompt, run:

2. Restart the command prompt and run telnet to open the Microsoft Telnet Client.

3. Run quit to exit the client:

How to Use Telnet in Windows to Test Open Ports

The Telnet syntax for testing open ports is:

The command accepts both symbolic and numeric addresses. For example:

After running the command, one of the following three options happen:

1. The command throws an error, indicating the port is not available for connection:

2. The command goes to a blank screen, indicating the port is available.

3. Running the command on an open port 23 displays the screen of the telnet host, confirming an established Telnet connection:

Note: Learn how Telnet differs from SSH in our comparison article Telnet vs SSH.

The Telnet communication protocol provides a way to establish a direct connection with a remote host. Although not a secure option for most tasks, there are use cases where Telnet is a viable option.

For further reading, check out the more secure option and learn how to use SSH to connect to a remote server in Linux or Windows.

How to exit telnet

The telnet program is a user interface to the TELNET protocol.

  • Description
  • Syntax
  • Protocol
  • Commands
  • Environment
  • Files
  • Examples
  • Related commands
  • Linux commands help

Description

The telnet command is used for interactive communication with another host using the TELNET protocol. It begins in command mode, where it prints a telnet command prompt (“telnet>“).

If telnet is invoked with a host argument, it performs an open command implicitly (see the Commands section below for details).

Syntax

Options

-4 Force IPv4 address resolution.
-6 Force IPv6 address resolution.
-8 Request 8-bit operation. This option causes an attempt to negotiate the TELNET BINARY option for both input and output. By default, telnet is not “8-bit clean” (it does not recognize 8-bit character encodings such as Unicode).
-E Disables the escape character functionality; that is, sets the escape character to “no character”.
-L Specifies an 8-bit data path on output. This option causes the TELNET BINARY option to be negotiated on output.
-a Attempt automatic login. Currently, this sends the username via the USER variable of the ENVIRON option if supported by the remote system. The username is retrieved via the getlogin system call.
-b address Use bind on the local socket to bind it to a specific local address.
-d Sets the initial value of the debug toggle to TRUE.
-r Emulate rlogin. In this mode, the default escape character is a tilde. Also, the interpretation of the escape character is changed: an escape character followed by a dot causes telnet to disconnect from the remote host. A ^Z (Control-Z) instead of a dot suspends telnet, and a ^] (Control-close bracket, the default telnet escape character) generates a normal telnet prompt. These codes are accepted only at the beginning of a line.
-S tos Sets the IP TOS (type-of-service) option for the telnet connection to the value tos.
-e escapechar Sets the escape character to escapechar. If no character is supplied, no escape character will be used. Entering the escape character while connected causes telnet to drop to command mode.
-l user Specify user as the user to log in as on the remote system. By sending the specified name as the USER environment variable, so it requires that the remote system support the TELNET ENVIRON option. This option implies the -a option, and may also be used with the open command.
-n tracefile Opens tracefile for recording trace information. See the set tracefile command below.
host Specifies a host to contact over the network.
port Specifies a port number or service name to contact. If not specified, the telnet port (23) is used.

Protocol

Once a connection is opened, telnet attempts to enable the TELNET LINEMODE option. If this fails, then telnet will revert to one of two input modes: either “character at a time” or “old line by line” depending on what the remote system supports.

When LINEMODE is enabled, character processing is done on the local system, under the control of the remote system. When input editing or character echoing is to be disabled, the remote system will relay that information. The remote system also relays changes to any special characters that happen on the remote system, so that they can take effect on the local system.

In “character at a time” mode, most text typed is immediately sent to the remote host for processing.

In “old line by line” mode, all text is echoed locally, and (normally) only completed lines are sent to the remote host. The “local echo character” (initially “^E“) may be used to turn off and on the local echo (this would mostly be used to enter passwords without the password being echoed).

If the LINEMODE option is enabled, or if the localchars toggle is TRUE (the default for “old line by line”; see below), the user’s quit, intr, and flush characters are trapped locally, and sent as TELNET protocol sequences to the remote side. If LINEMODE has ever been enabled, then the user’s susp and eof are also sent as TELNET protocol sequences, and quit is sent as a TELNET ABORT instead of BREAK. There are options (see toggle autoflush and toggle autosynch, below) which cause this action to flush subsequent output to the terminal (until the remote host acknowledges the TELNET sequence) and flush previous terminal input (in the case of quit and intr).

Commands

The following telnet commands are available. Unique prefixes are understood as abbreviations.

After establishing a connection, any commands associated with the remote host in /etc/telnetrc and the user’s .telnetrc file are executed, in that order. The format of the telnetrc files is as follows: Lines beginning with a #, and blank lines, are treated as comments (ignored). The rest of the file should consist of hostnames and sequences of telnet commands to use with that host. Commands should be one per line, indented by whitespace; lines beginning without whitespace are interpreted as hostnames. Lines beginning with the special hostname ‘DEFAULT’ will apply to all hosts. Hostnames including ‘DEFAULT’ may be followed immediately by a colon and a port number or string.

Environment

telnet uses at least the HOME, SHELL, DISPLAY, and TERM environment variables. Other environment variables may be propagated to the other side via the TELNET ENVIRON option.

Files

Examples

Attempts to open a connection to the remote host myhost.com. If a connection is established, the host prompts for a login name and password.

Attempts to open a connection to the remote host myhost.com on port 5555, using the login name myusername. If successful, the host prompts for myusername‘s password.

Opens a local telnet> prompt, where you can enter any of the commands listed above. For example, entering the following command at the prompt:

. attempts to open a connection to myhost.com, as in our first example.

Related commands

rlogin — Begin a session on a remote system.
ssh — Login to a remote system securely.

To many of you, this is not an interested post. However, it will not cost much for recording it here as a reference.

Question: You’re accessing Linux command prompt in front of server console or via remote access client (be it a insecure telnet or encrypted SSH connection).

Then, from that Linux command prompt, you make a telnet connection to other telnet server (be it a Unix/Linux-based or the Windows Telnet server).

While at telnet login prompt, you find out that is not the right telnet server to access and want to quit immediately.

So, how could you exit from the telnet login prompt immediately, without waiting for it to time out or forcibly terminate the telnet client process?

Answer: I find out that the telnet client of either Windows Vista Ultimate or Red Hat Enterprise Linux 4 supports the same “escape” key.

This special key, better known as “escape character” brings up the telnet > command prompt instantly when it’s pressed.

As seen in this following screenshot, the “escape character” is ^] . That’s to say, press CTRL and ] together for the telnet > command prompt and just enter quit command to end the telnet client process properly:

With this “proper” way, there is no need to wait for time out, simply close Putty window, or execute kill -9 command from another session.

Syntax

Syntax (EX Series Switches)

Syntax (Junos OS Evolved)

Description

Open a telnet session to a remote system. Type Ctrl+] to escape from the telnet session to the telnet command level, and then type quit to exit from telnet.

For Junos OS Evolved, use the routing-instance mgmt_junos option to access a remote system through the management interface.

Options

Name or address of the remote system.

(Optional) Use an 8-bit data path.

(Optional) Bypass the normal routing tables and send ping requests directly to a system on an attached network. If the system is not on a directly attached network, an error is returned. Use this option to ping a local system through an interface that has no route through it.

(Optional) Open an IPv4 or IPv6 session, respectively.

(Optional) Interface name for the telnet session. (This option does not work when default-address-selection is configured at the [edit system] hierarchy level, because this configuration uses the loopback interface as the source address for all locally generated IP packets.)

(Optional) Name of a particular logical system for the telnet attempt.

(Optional) Name of a particular tenant system for the telnet attempt.

(Optional) This option is not supported for Junos OS Evolved Release 18.3R1. Do not attempt to determine the hostname that corresponds to the IP address.

(Optional) Port number or service name on the remote system.

(Optional) Name of the routing instance for the telnet attempt.

(Optional) This option is not supported for Junos OS Evolved Release 18.3R1. Source address of the telnet connection.

Additional Information

You can limit the number of times a user can attempt to enter a password while logging in through telnet. To specify the number of times a user can attempt to enter a password to log in through telnet, include the retry-options statement at the [ edit system login ] hierarchy level.

Required Privilege Level

Output Fields

When you enter this command, you are provided feedback on the status of your request.

Sample Output

telnet

Release Information

Command introduced before Junos OS Release 7.4.

The following options are deprecated in Junos OS Evolved Release 18.3R1: bypass-routing , interface , no-resolve , and source .

The command tenant option is introduced in Junos OS Release 19.2R1 for SRX Series.

Table of Contents

How do I exit a telnet session?

To exit the Telnet session, type Ctrl + ] on your keyboard. This changes the command prompt to show as telnet>. Back in the terminal, type in the word ‘close’ to close the session.

What is escape character in telnet?

The telnet escape character may be either ^] or ^t. You will also get the telnet prompt if telnet does not recognize the remote hostname you use. In this case you are not connected to the foreign machine but are just running telnet. You can quit telnet or tell telnet to open some other machine.

How do I telnet from command prompt?

To use telnet, follow the steps below:

  1. First, find out the ip address of the server/main computer.
  2. Select the Windows key and the R key.
  3. In the Run box type CMD.
  4. Select OK.
  5. Type Telnet 13531.
  6. If you see a blank cursor then the connection is fine.

How do I run telnet in debug mode?

Use the telnet interface’s debugging capabilities by entering the telnet command without flags. Type open host where host is the name of the machine. Press Ctrl-T to get to the tn%gt; prompt. At the tn> prompt, type debug for debugging mode.

How do I change the escape character in telnet?

  1. Press the telnet escape character: ^] by default ( CTRL + ] ). You can change the escape character by using the -e option. Example: # telnet -e ² myhost port. .
  2. Define character mode at telnet prompt: telnet> mode char. .

What to do after telnet connects?

Exit from Telnet. Set the terminal type for the connection, turn on local echo, set authentication to NTLM, set the escape character, and set up logging. SET NTLM turns on NTLM.

What can you do with telnet connection?

What are common uses for Telnet? Telnet can be used to test or troubleshoot remote web or mail servers, as well as for remote access to MUDs (multi-user dungeon games) and trusted internal networks.

How do I open a telnet port in Windows 10?

  1. Click Start.
  2. Select Control Panel.
  3. Choose Programs and Features.
  4. Click Turn Windows features on or off.
  5. Select the Telnet Client option.
  6. Click OK. A dialog box appears to confirm installation. The telnet command should now be available.

What is port for telnet?

23
The default port for Telnet client connections is 23; to change this default, enter a port number between 1024 and 32,767.

How do I close a Vscode terminal?

11 Answers. You can terminate with the Trash icon like you do, or press Ctrl + C . That’s the shortcut from the default Terminal application and it also works in Visual Studio Code.

You can use Windows’ Telnet Client to confirm whether or not communications are getting through to a specified server and port or not.

If you are using Windows Vista or Windows 7, the Telnet Client is disabled by default. You can enable it by going to Control Panel | Programs | Programs and Features | Turn Windows features on or off, and enable the “Telnet Client” option. It may take a couple minutes for the change to complete.

Press Windows-R to open the “Run” dialog, then type “cmd” in it and press OK. This will open a command prompt window. It will be a black window with some white text that says something like “C:\>”. This is a command prompt, similar to the old DOS operating system. Please note that the text shown in your prompt may vary, this is not important.

At the prompt, type “telnet address port” where “address” is the IP address, computer name, or domain name you want to connect to (as appropriate), and “port” is the TCP/IP communications port you want to connect on, then press enter.

When troubleshooting the USB License Manager application to activate your MicroSurvey USB License Key:

C:\> telnet MicroSurveyLicenseServer.com 1433

When troubleshooting a connection to your USB Network License Server to run a MicroSurvey product:

C:\> telnet YourNetworkLicenseServer 8765

When troubleshooting OfficeSync (Office Manager or Job Monitor) communication errors:

C:\> telnet OfficeSyncServer.com 1433

After executing the telnet program, you will see one of two results:

1) The command prompt screen will go blank.

This means that nothing is blocking communications between your workstation and the specified server or address, on the specified port. You will not see any sort of “success” message etc, because we are not really connecting to a telnet server so there is no return message that will be displayed. We are using telnet simply as a tool to test basic connectivity problems.

Press Ctrl-] to open the telnet prompt

At the telnet prompt, type quit.

Then at the command prompt, type exit.

You can stop troubleshooting a connection problem. If you are still having some sort of connection errors in your application it is due to some other problem, and you should contact MicroSurvey Technical Support with further details.

or 2) You will see a connection error, something like “Could not open connection to the host on port x: Connect failed”.

This confirms that something is blocking communications between your workstation and the specified computer or server, on the specified port. Unfortunately this will not provide any further clues as to the source of the blockage; however, typical sources include personal firewall software running on your workstation (like Norton Personal Security, for example), enterprise firewall software running on your local network (like Microsoft ISA Server, for example), a hardware firewall, a router with integrated firewall features, a cable or ISDN modem with integrated firewall features, or even your Internet Service Provider (or their secondary providers) may be blocking specific communication ports.

Please contact your local IT or Network Support staff for further assistance as to any firewall software/firewall that may be present. MicroSurvey Technical Support cannot help you determine this.

I start telnet by telnet host port . How do I stop it in Windows? Shockingly, Ctrl + C doesn’t work.

Welcome to the trenches, nothing is “shocking” on Windows. Pacerier

@Pacerier `telnet` predates Windows, and Microsoft had excellent UI standards in the 80s and 90s. Cees Timmerman

The reason Ctrl+C doesn’t interrupt or suspend the connection is that an interrupt signal or a Ctrl+C often needs to be passed through to the remote end (so you can break programs there, if you’re working on a remote shell), which wouldn’t be possible if the telnet client intercepted it for its own purposes. blubberdiblub

Answer – 1 verified

It should have printed something along the lines of:

Since ^X is Ctrl X , try Ctrl ] for ^] .

You should then enter the telnet console, where you can enter quit to leave telnet.

on Windows, run telnet with out arguments to see what the escape character is. On some localized Windows versions where ] is only available with `Alt Gr` key, the key combination is `Ctrl`+`+`. mihi

As far as I remember Ctrl+5 was equivalent with ^] on my (Norwegian) keyboard. hlovdal

Ctrl+¨ on Windows 7 and sv/fi layout. mkataja

On `Ubuntu` `Ctrl + ]`, `quit` worked for me user1527227

Doesn’t work. It says: `Microsoft Telnet> ^]` and next line shows: `Invalid Command. type ?/help for help` Pacerier

@Pacerier Type quit after that to back to the dos. Good Luck. QMaster

From CMD write telnet “hostip/name” “portnumber” then do disconnect. Press down the CTRL key and another random key on the keyboard until you find the correct one. And then write “quit” press enter. ColacX

I never noticed that before. amazing whats right in front of your face WernerCD

It’s CTRL+$ (i tested this on windows 10) This is the output from my console: Welcome to Microsoft Telnet Client Escape Character is ‘CTRL+$’ Microsoft Telnet> quit C:\WINDOWS\system32> Kris Nobels

. and on my German keyboard it was Strg+AltGr+9, then hit return Abdull

On my swedish keyboard it was `Ctrl`+`¨` Krycke

@Krycke The same for Swiss Keyboard, the key `]` must be used with `AltGr` but for that purpose, we just press the `Ctrl`+`¨` рüффп

On German keyboar layout, press `Strg` + `Alt Gr` + `9` Abdull

On Swiss German Keyboard it is CTRL+¨ raudi

On my Mac with Norwegian keyboard, `]` is `Alt` + `9`. Typing `Ctrl` + `Alt` + `9` yields `9` and is not recognised by telnet as escape character. I had to switch to U.S. input source under `Keyboard` –> `Input Sources` to be able to type `Ctrl` + `]`. rlovtang

To add to rlovtang’s answer: The ] character on US keyboard layout is what is marked as the ^¨ key on the norwegian keyboard. Magne

actually, I discovered that you don’t have to switch keyboard layout. With the norwegian layout it’s as easy as typing: `ctrl + å` as you can see in the quoted answer below. Solution in other keyboard language layouts is also listed there. Magne

In Latinamerican layout is `ctrl + > ` Alejandro Ruiz

Ctrl + Ç on PT-BR keyboard Gus

On danish keyboard for windows: As with @rlovtang suggestion of switching keyboard. Alt + Shift to switch keyboard language or select directly in the buttom right corner of the Task Bar. Then ctrl + ¨ (where ¨ results in ]) Sonaten

with german keyboard layout on macos `CTRL+OPTION+6` then type close and enter muuvmuuv

In turkish keybord, for Windows, it’s CTRL+ü Kuvalya

Answer – 2

Type quit to exit telnet in windows.

Worked on MacOS X as well 😉 karlingen

Also works in Linux. 에이바

From @Isaac: This also works on Windows 8.1. fixer1234

Only this works to me. Felipe

It didn’t in linux [Centos 6.6] Alexander

@Alexander you have to press `Ctrl + ]` and only then when `telnet>` prompt appears enter `quit`. Gacha

For some reason I get `Microsoft Telnet> ^] Invalid Command. type ?/help for help` but `quit` works. Thanks. Charles Clayton

This applies to the telnet interpreter, and not to a running telnet connection, that was asked for oo_dev

Answer – 3

The ^] means ctrl + right bracket. As strange as that is, it works. You’ll be taken to the telnet prompt, where you can type quit .

On international keyboards the ] character is often not a single key, and needs to be replaced with some other key. The correct key is typically the key to the right of P or the next key after that.

Here’s a list based on comments below:

  • Finnish, Swedish, Norwegian, Danish: ctrl + å
  • French: ctrl + 6
  • German, Turkish: ctrl + ü
  • Swiss: ctrl + ¨
  • Hungarian: ctrl + 5
  • Portuguese: ctrl + ´
  • Dutch, Belgian: ctrl + $
  • Canadian French: ctrl + ç
  • Italian: ctrl + +

Quote from @jtbandes answer here: https://superuser.com/a/427/192525 All creds to him.

PS: Answer reproduced here for your convenience, since google took me to this question first, and none of the other answers here was sufficient for my case. The question How to send the escape character on OS X terminal? could be seen as a duplicate (more generic version) of this question, since the OP’s problems are basically the same.

French keyboard here on Win7 with a remote session on a Ubuntu 17.10 VM via Putty. I got the telnet prompt back with ctrl+5 not ctrl+6 Diego Tercero

For my German keyboard it’s actually ctr++, not ctr+ü dominik andreas

If you use Turkish Q on ubuntu CTRL + 5 is the key Erdinç Çorbacı

If you use latin american spanish CTRL+5 is the key too Gustavo Arias Méndez

Doesn’t seem to work in Portuguese. (Windows 10). Also, telnet says the escape char is ‘]’, not ‘^]’. D. Pardal

@D.Pardal The `^` in `^]` just refers to the CTRL button, since it is marked by an `^` on the keyboard. So it just means `CTRL + ]` so telnet is right that the character itself is just `]` Magne

Thank @GustavoAriasMéndez in Spanish keyboard using SSL terminal conected to unix, control + 5 works! Hernaldo Gonzalez

On Hungarian layout the key is ctrl+ú C1sc0

Answer – 4

On debian 9, typing :

Allows you to show the prompt from telnet, then only type :

Follow the procedure below to use telnet.

Only one user at a time can log on to perform remote maintenance.

If you are using Windows Vista, you must enable the telnet server and telnet client beforehand.

Use the IP address or the host name of the machine to start telnet.

% telnet “IP address”

Enter your user name and password.

For details about the user name and password, consult your network administrator.

For user authentication, enter a login user name and password.

For user code authentication, enter a user code in User Name.

Enter a command.

The configuration message about saving the changes appears.

Enter “yes” to save the changes, and then press the [Enter] key.

If you do not want to save the changes, enter “no”, and then press the [Enter] key. To make further changes, enter “return” at the command line, and then press the [Enter] key.

If the message “Can not write NVRAM information” appears, the changes are not saved. Repeat the procedure above.

When the changes are saved, the network interface board is reset automatically with that changes.

When the network interface board resets, the print job in print process will be printed. However, print jobs in queue will be canceled.

The telnetlib module provides a Telnet class that implements the Telnet protocol. See RFC 854 for details about the protocol. In addition, it provides symbolic constants for the protocol characters (see below), and for the telnet options. The symbolic names of the telnet options follow the definitions in arpa/telnet.h , with the leading TELOPT_ removed. For symbolic names of options which are traditionally not included in arpa/telnet.h , see the module source itself.

The symbolic constants for the telnet commands are: IAC, DONT, DO, WONT, WILL, SE (Subnegotiation End), NOP (No Operation), DM (Data Mark), BRK (Break), IP (Interrupt process), AO (Abort output), AYT (Are You There), EC (Erase Character), EL (Erase Line), GA (Go Ahead), SB (Subnegotiation Begin).

class telnetlib. Telnet ( host=None, port=0 [ , timeout ] ) В¶

Telnet represents a connection to a Telnet server. The instance is initially not connected by default; the open() method must be used to establish a connection. Alternatively, the host name and optional port number can be passed to the constructor too, in which case the connection to the server will be established before the constructor returns. The optional timeout parameter specifies a timeout in seconds for blocking operations like the connection attempt (if not specified, the global default timeout setting will be used).

Do not reopen an already connected instance.

This class has many read_*() methods. Note that some of them raise EOFError when the end of the connection is read, because they can return an empty string for other reasons. See the individual descriptions below.

A Telnet object is a context manager and can be used in a with statement. When the with block ends, the close() method is called:

Changed in version 3.6: Context manager support added

RFC 854 – Telnet Protocol Specification

Definition of the Telnet protocol.

Telnet Objects¶

Telnet instances have the following methods:

Telnet. read_until ( expected , timeout = None ) В¶

Read until a given byte string, expected, is encountered or until timeout seconds have passed.

When no match is found, return whatever is available instead, possibly empty bytes. Raise EOFError if the connection is closed and no cooked data is available.

Read all data until EOF as bytes; block until connection closed.

Read at least one byte of cooked data unless EOF is hit. Return b” if EOF is hit. Block if no data is immediately available.

Read everything that can be without blocking in I/O (eager).

Raise EOFError if connection closed and no cooked data available. Return b” if no cooked data available otherwise. Do not block unless in the midst of an IAC sequence.

Read readily available data.

Raise EOFError if connection closed and no cooked data available. Return b” if no cooked data available otherwise. Do not block unless in the midst of an IAC sequence.

Process and return data already in the queues (lazy).

Raise EOFError if connection closed and no data available. Return b” if no cooked data available otherwise. Do not block unless in the midst of an IAC sequence.

Return any data available in the cooked queue (very lazy).

Raise EOFError if connection closed and no data available. Return b” if no cooked data available otherwise. This method never blocks.

Return the data collected between a SB/SE pair (suboption begin/end). The callback should access these data when it was invoked with a SE command. This method never blocks.

Telnet. open ( host, port=0 [ , timeout ] ) В¶

Connect to a host. The optional second argument is the port number, which defaults to the standard Telnet port (23). The optional timeout parameter specifies a timeout in seconds for blocking operations like the connection attempt (if not specified, the global default timeout setting will be used).

Do not try to reopen an already connected instance.

Raises an auditing event telnetlib.Telnet.open with arguments self , host , port .

Telnet. msg ( msg , * args ) В¶

Print a debug message when the debug level is > 0. If extra arguments are present, they are substituted in the message using the standard string formatting operator.

Telnet. set_debuglevel ( debuglevel ) В¶

Set the debug level. The higher the value of debuglevel, the more debug output you get (on sys.stdout ).

Close the connection.

Return the socket object used internally.

Return the file descriptor of the socket object used internally.

Telnet. write ( buffer ) В¶

Write a byte string to the socket, doubling any IAC characters. This can block if the connection is blocked. May raise OSError if the connection is closed.

Raises an auditing event telnetlib.Telnet.write with arguments self , buffer .

Changed in version 3.3: This method used to raise socket.error , which is now an alias of OSError .

Interaction function, emulates a very dumb Telnet client.

Multithreaded version of interact() .

Telnet. expect ( list , timeout = None ) В¶

Read until one from a list of a regular expressions matches.

The first argument is a list of regular expressions, either compiled ( regex objects ) or uncompiled (byte strings). The optional second argument is a timeout, in seconds; the default is to block indefinitely.

Return a tuple of three items: the index in the list of the first regular expression that matches; the match object returned; and the bytes read up till and including the match.

If end of file is found and no bytes were read, raise EOFError . Otherwise, when nothing matches, return (-1, None, data) where data is the bytes received so far (may be empty bytes if a timeout happened).

If a regular expression ends with a greedy match (such as .* ) or if more than one expression can match the same input, the results are non-deterministic, and may depend on the I/O timing.

Telnet. set_option_negotiation_callback ( callback ) В¶

Each time a telnet option is read on the input flow, this callback (if set) is called with the following parameters: callback(telnet socket, command (DO/DONT/WILL/WONT), option). No other action is done afterwards by telnetlib.

I’m running telnet command on a host for a given port (which is open), it returns 0 (success).

For trying telnet manually, I type the following command, then I press control+bracket i.e. ^] , then press Enter key, then I get to telnet> prompt, where if I type close or quit , it comes back to the $ prompt and seeing exit status of last command shows 0 for (success) as port 2878 is open (as per the telnet command’s output).

Now, I wanted to run the same operation without any human intervention i.e. I don’t want to manually give ^] and press Enter key to come to the telnet> prompt, then enter close (or quit ) telnet command to finally come back to the $ prompt.

For this, I tried using echo -e command’s option and giving ^] , n (for new line character i.e. Enter key) and close command (for telnet> prompt so that I come back to $ prompt). Doing this, kind of worked as expected but for the exit status of last command echo $? , I’m getting 1 (instead of 0). Why?

or tried the here-doc method as well, but not sure why it’s returning 1 (as exit code) for a valid port which is open.

How can I automatically exit from telnet if the port is open and get 0 as exit code? If there’s a way to capture the output of the previous command, may be I can grep the ‘Connection closed by foreign host.’ string to mark it successful (0).

A slight improvement to the answer provided by Matthew above which allows you to use it inside shell scripts:

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Access the menu interface using any of the following methods.

A direct serial connection to the switch’s console port, as described in the installation guide you received with the switch

A Telnet connection to the switch console from a networked PC or the switch’s web browser interface. Telnet requires that an IP address and subnet mask compatible with your network have already been configured on the switch.

NOTE: This section assumes that either a terminal device is already configured and connected to the switch. See the Installation and Getting Started Guide for your switch.

How to start a menu interface session

In its factory default configuration, the switch console starts with the CLI prompt. To use the menu interface with Manager privileges, go to the Manager level prompt and enter the menu command.

Use one of these methods to connect to the switch:

A PC terminal emulator or terminal

Do one of the following:

If you are using Telnet, go to step 3.

If you are using a PC terminal emulator or a terminal, press [Enter] one or more times until a prompt appears.

When the switch screen appears, do one of the following:

If a password has been configured, the password prompt appears.

Type the Manager password and press [Enter] . Entering the Manager password gives you manager-level access to the switch. (Entering the Operator password gives you operator-level access to the switch. See the Access Security Guide for your switch.)

If no password has been configured, the CLI prompt appears. Go to the next step.

When the CLI prompt appears, display the Menu interface by entering the menu command. For example:

results in the following display:

Example of the Main Menu with Manager Privileges

How to exit telnet

For a description of Main Menu features, see Main Menu features.

NOTE: To configure the switch to start with the menu interface instead of the CLI, go to the Manager level prompt in the CLI, enter the setup command, and in the resulting display, change the Logon Default parameter to Menu . For more information, see the Installation and Getting Started Guide you received with the switch.

How to end a menu session and exit from the console

The method for ending a menu session and exiting from the console depends on whether, during the session, you made any changes to the switch configuration that require a switch reboot to activate. (Most changes via the menu interface need only a S ave , and do not require a switch reboot.) Configuration changes that need a reboot are marked with an asterisk (*) next to the configured item in the menu and also next to the Switch Configuration item in the Main Menu.

Example indication of a configuration change requiring a reboot

How to exit telnet

In the current session, if you have not made configuration changes that require a switch reboot to activate, return to the Main Menu and press [0] (zero) to log out. Then just exit from the terminal program, turn off the terminal, or quit the Telnet session.

If you have made configuration changes that require a switch reboot— that is, if an asterisk ( * ) appears next to a configured item or next to Switch Configuration in the Main Menu:

Return to the Main Menu.

Press [6] to select Reboot Switch and follow the instructions on the reboot screen.

Rebooting the switch terminates the menu session, and, if you are using Telnet, disconnects the Telnet session.

Exit from the terminal program, turn off the terminal, or close the Telnet application program.

Scrapy comes with a built-in telnet console for inspecting and controlling a Scrapy running process. The telnet console is just a regular python shell running inside the Scrapy process, so you can do literally anything from it.

The telnet console is a built-in Scrapy extension which comes enabled by default, but you can also disable it if you want. For more information about the extension itself see Telnet console extension .

It is not secure to use telnet console via public networks, as telnet doesn’t provide any transport-layer security. Having username/password authentication doesn’t change that.

Intended usage is connecting to a running Scrapy spider locally (spider process and telnet client are on the same machine) or over a secure connection (VPN, SSH tunnel). Please avoid using telnet console over insecure connections, or disable it completely using TELNETCONSOLE_ENABLED option.

How to access the telnet console¶

The telnet console listens in the TCP port defined in the TELNETCONSOLE_PORT setting, which defaults to 6023 . To access the console you need to type:

By default Username is scrapy and Password is autogenerated. The autogenerated Password can be seen on Scrapy logs like the example below:

Default Username and Password can be overridden by the settings TELNETCONSOLE_USERNAME and TELNETCONSOLE_PASSWORD .

Username and password provide only a limited protection, as telnet is not using secure transport – by default traffic is not encrypted even if username and password are set.

You need the telnet program which comes installed by default in Windows, and most Linux distros.

Available variables in the telnet console¶

The telnet console is like a regular Python shell running inside the Scrapy process, so you can do anything from it including importing new modules, etc.

However, the telnet console comes with some default variables defined for convenience:

I’ve recently purchased 4 of these hand held’s off ebay but every time I boot them up they seem to be going straight into the telnet mode which I can’t exit out from I have the exact same models that I support and there is a toggle mode that when I press CTRL+ALT+0(F10)I’m able to navigate and escape but with these 4 I cant, I’ve tried warm booting, cold booting really not getting any where.

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Have you tried pushing in the yellow scanning button on top and holding the power button in at the same time? I *think* that this warm boots the device if memory serves me right – its been a year and half since I have supported these devices. Also do you have a dock for the barcode scanners? Have you tried navigating the File System and seeing if there are any scripts that might be applied that would prevent you from exiting Telnet?

Also you can use the dock to remove the programs, uninstall/reinstall the profile, etc. Have you tried (if you have the dock) to remove the telnet profile completely? Usually there is a profile installation utility that you can put on your computer and then use this to push the profile to the barcode scanner.

@Craig4129 yes hi have done that as well as a cold boot as for the dock I do not have the software so i’m pretty much stuffed spent half the day googling and going through forums

I bought the same ones through Ebay.

I managed to work out the keys and exit passwords.

Probably not a good idea to share them publicly, but Im happy to help you with them in private email messages.

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    How to exit telnet

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How to exit telnet

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How to exit telnet

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How to exit telnet

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Solved – How to exit a telnet session?

How to exit a telnet session?

It’s funny, but I was fumbling with the terminal to exit a telnet session today. I rarely have to use telnet so I’m not much experienced with it. But if someone ever want to exit from a telnet session this is what you have to do.

Basically when you start a telnet session, this is what you would see most of the times:

$ telnet localhost 80
Trying 127.0.0.1.
Connected to localhost.
Escape character is ‘^]’.

Now what? Pressing Ctrl + c, z, x, d will not do anything. I was too lazy that I didn’t pay much attention to what was printed in the console. If I had read that, I would have easily exit the session.

It says: Escape character is ‘^]’.

So that’s it. You need to press Ctrl + ] keys and it will take you back to the telnet prompt where you can either press Ctrl + D or enter the command “quit” and press enter.

$ telnet localhost 80
Trying 127.0.0.1.
Connected to localhost.
Escape character is ‘^]’.
^]
telnet> quit
Connection closed.

One thing to note is that I use Terminator as my terminal emulator and this method doesn’t work in it. I Still can’t exit from that (: But this definitely works in the gnome terminal.

I hope this will help someone 🙂 Please don’t forget to leave a comment if you ever come across this post. Feel free to correct me or add any methods you know other than this.

In earlier posts, we saw how to install Memcached server on Mac OS and Unix systems. After that we worked on to start Memcached server at boot time as a daemon process in Mac OS.

In this tutorial, we will go through some of the basic Memcached telnet commands that we can use to check the health of the Memcached server. These commands are very helpful in debugging purposes and can be used from any operating system with telnet installed.

If you are on a UNIX system, then using ps -eaf | grep memcached command will get you the port Memcached server is running on.

For example, when I run this command on my UNIX system, I got below output:

So Memcached server is running on TCP port 11111 and in verbose mode (-vv). If you want to run as daemon process then use -d option in the startup command.

Memcached Telnet Commands

To connect to memcached server with telnet and start a session:

To store data in Memcached server with telnet:

To retrieve data from Memcached through telnet:

To overwrite the existing key:

To delete the key:

To get the server statistics:

To clear the cache data:

To quit the telnet session:

Memcached Server Telnet Example

How to exit telnet

In the next post on memcached, I will provide information about using memcached client in Java.

This command must be executed from the enable mode of the controller .

Description

This command initiate a remote telnet session from the controller to a remote host.

Syntax

Enter the user name of the remote host.

Enter the IP address of the remote host.

Enter the telnet port number of the remote host. This is an optional parameter.

Usage Guidelines

The command usage guidelines are as follows:

This feature is supported from the SSH session of the controller only.

There is an inactivity timeout for the CLI sessions. When an administrator initiates a remote session (inner) from the controller ’s SSH session (outer), and the remote session takes more time than the inactivity timeout session, the outer session times out although the inner session is active. The administrator has to log back in to the outer session once logged off from the inner session.

Designated telnet client control keys do not work for remote telnet sessions. When an administrator initiates a remote telnet session (inner) from the controller ’s SSH session (outer), the designated telnet client control keys functions for the outer SSH session only. The administrator should designate unique control keys for each remote telnet sessions.

To end the remote host session, execute the exit command. The remote host displays the following message:

Connection closed by foreign host.

Example

The following command initiates a remote telnet session from the controller to a remote host:

(host) #telnet admin 192.0.2.1

The following command ends the remote host session: