Of course, telnet/ftp are not secure until you can get in the device and configure it for usernames/passwords/SSH/sftp. BTW - It would be nice if Apple would enhance Terminal to enable a ZTerm/PuTTY type virtual serial port for accessing Cisco devices. Telnet and nc are common tools used to test port connectivity from Linux server. Telnet can be used to test tcp port connections, where as nc can be used to test both tcp/udp ports connectivity. Make sure telnet and nc tools are installed on the Linux server you are trying to test connectivity. Also the telnet client is not included by default in many distros. For instance it is very common in docker-land to face the need of installing several tools that are taken otherwise for granted. For example, Official OS docker images most likely will be shipped with a shell and its built-ins.
My previous post was about RouterOS Mac-Telnet application for Linux users where I talked about the MAC-Telnet client I created for Linux users.
Since then, I have both started porting it to OS X and to create a daemon version of MAC-Telnet, called “mactelnetd”. You can look at the different branches at github.com.
To use mactelnetd, install MAC-Telnet from the github link, using either the latest .deb file from the download section (if you are on Ubuntu or Debian), or download the sources and compile it yourself. You can find instructions for this on my previous post. you first need to edit the /etc/mactelnetd.users file. This file consists of the users and their respective passwords for logging into the server. I wish we wouldn’t have to write the passwords in plain text, but the authentication method used in the mac-telnet protocol demands that we know the actual password, unlike ssh/regular telnet, where the password can be stored as a hash sum.
The format of /etc/mactelnetd.users is like this:
Here I have activated the user account haakon, with apssword “mypass”. It is important that the user names that you enter into this file is existing user names from your Linux machine. The mactelnetd daemon will check /etc/passwd for home directory, and what shell to spawn for the user, as any regular terminal server.
When you have created/modified this file to your wishes, you can start the server daemon:
If there were no error messages, it spawned successfully and you can watch it’s log entries via syslog.
Here you see the results of me logging into my Linux Desktop machine from a MikroTik Router using the RouterOS command “tool mac-telnet 1c:6f:65:2c:98:b7”
If you want to shut down the mactelnetd server, simply write “sudo killall mactelnetd” in your shell.
FUN TIP: If you want “fancy” terminal promt like RouterOS has, with syntax coloring on your Linux machine (logging in via console, xterm, ssh or mactelnet), you can install the shell “fish“, and then change your user settings to use it as the default shell by issuing:
Mac Os Install Telnet
NB: Be sure that the file /usr/bin/fish exists, and change “myusername” with your username, and remember to test logging into a second console, just to be sure you did this correctly, before logging out of your current terminal. To revert, set /bin/bash as your shell again, or what ever shell you previously used.
Mac Telnet Linux
Here’s a direct link to the latest Ubuntu/Debian package at the time of writing: