Skip to main content

Featured Post

Product Design of a 4 wheel differential drive robot

Post a Comment

Testing NAT Port Forwarding and reverese NAT

For a long time I have been trying to configure port forwarding using NAT. But every attempt was futile...  Finally I found that my port forwarding works just fine. But it just appears to be not working because my router doesn't support reverse NAT. In this post I will show you guys how to test whether you configure your NAT correctly or not. (Read a detailed write up by shane. Link)

First make a port forwarding rule in your router say 1600. Download this little tool called simple internet tools. Install it and open port listener and select your internal IP(192.168.x.x). Then type your port number and press start listening.

Go to this site and check whether it says port is opened. If your connection is successful you will notice it in the port listener application.

Then go to your browser and type your internet ip address. (You can find it from www.whatismyip.com) . Tnen type your port number after a colon. (116.211.22.12:1600). Your browser shows a webpage not available window. Check your port listener. If you find a connection successful message it means your router supports reverse NAT. Otherwise reverse NAT is not available.

You can also check it by an nc command like this.

nc 116.211.22.12 1600

If you didn't want to test the connection using the above site you can do it by nc from a remote ssh account. Login to your ssh account and try to connect it with nc.

Labels:

Comments

Post a Comment

Popular posts from this blog

Plymouth theme for Ubuntu

Bored of having the same boot animation screen again and again? There are plenty of Plymouth themes available out there. This is a theme I created by slicing some cool gif files I found online. You can download the theme and find the installation steps on my github account. ( https://github.com/krishnan793/PlymouthTheme-Cat )  The theme is created for Ubuntu 16.04. But this can be installed on previous versions with slight modification. If you have a slow computer then you can watch the whole animation loops. (The VM I used to record the screen was fast though. :))
Post a Comment
Read more

Getting started with GPIO (Testing GPIO with a multimeter)

There are 65 possible GPIO pins that you can control. Some of the GPIO pins are normally configured to different functions. Let's play with one of them. Go to the beaglebone website and figure out the header pin corresponding to gpio23. The gpio23 is mapped to the 13th header pin. In this tutorial we are testing the gpio23 output using a multimeter (Do not connect an LED directly to BBB IO pin). First go to following directory cd /sys/class/gpio / Then make gpio23 available echo 23 > export A new directory will be created. Open gpio directory. cd gpio23 The direction of IO will be normally set as in (input).  To make it as output, echo out > direction Then set the pin to high using echo 1 > value Measure the voltage at pin 13 of P8 header. If its 3.3 V then you are on the right track. Pin 1 and 2 will be ground. You can connect the negative terminal of multimeter to pin 1 or 2. To set output as zero, echo 0 > value After finished wit...
Post a Comment
Read more

Remote access your BeagleBone Black using vnc

Before going into how to share desktop with your BBB I assume you have a proper ssh access to your BBB. (through USB) (if not read this ) Also this tutorial is for BBB with Debian installed (type cat /etc/*-release to know which distro you are currently using. Or refer here ) First install the vnc server in BBB.(After logging into BBB) ssh root@192.168.7.2 apt-get install x11vnc Then go to your local computer and open a terminal window. Install a vnc viewer like vinagre. sudo apt-get install vinagre Now its time to start vnc server in BBB. x11vnc -auth /var/run/lightdm/root/:0 -forever This will start a vnc server at port 5900. Note this server setup is temporary. If you want to remotely connect to your BBB after a reboot type the above command again. Go to your local computer and type  vinagre 192.168.7.2::5900 A remote desktop will be shown if all goes well. Try exploring other options in x11vnc using (in BBB) man x11vnc Th...
Post a Comment
Read more