Why do I Want a Static IP Address?

An IP Address (Internet Protocol) is a a set of numerical digits that identify a device and its location on a network.  It is similar to your house address except that it uses numbers.  If your Raspberry Pi is connected your Router then it will automatically be given its own IP address.  The issue is that this address will change each time you log on and off.   This is know as a Dynamic Address - it changes.  A Static IP Address remains the same all the time and makes it easier to access your Pi.

Getting Started

Basically you need to identify your current network settings and modify them so that the IP Address remains static.  Firstly check that your address is not already Static .

In the LX Terminal type:
cat /etc/network/interfaces   

This will load an overview of the connected network devices, you are looking for the third line which states: iface eth0 inet dhcp The DHCP means that your IP Address is Dynamic and will change when you turn the Pi off.

Collecting the Information: Part 1

The next part is to collect the information relating to the your current IP Address, the Broadcast address and the Netmask address, these are abbreviated to Inet, Bcast and Mask.  All the values are on the same line so it is easy to coppy them down in one go

In the LX Terminal type:
ifconfig 

Write these three values down as you will require them later
  • inet addr
  • Bcast
  • Mask

Collecting the Information: Part 2

The next part is to collect the Destination and the Gateway address.  There are two commands that you can use the access them.

In the LX Terminal type:
netstat - nr  or  route -n

Write these two values down as you will require them later
  • Destination
  • Gateway

Making the IP Address Static

The final part of the Static IP process is to open the original cat /etc/network/interfaces   file in edit mode.  

In the LX Terminal type:
sudo nano/etc/network/interfaces

Change the iface etho0 inet dchp to iface etho0 inet static 
Next enter the previous information you collected in parts 1 and 2 , in a list below the statement  iface etho0 inet static, 

address       192.34..... etc     (inet address)
broadcast   194.34..... etc    (Bcast)
netmask     255.25..... etc    (Mask)
network     192.34..... etc    (Destination )
gateway      192.34..... etc   (Gateway)

Remember to replace the addresses with the ones from your network that you collected earlier.

And to Finish with....

If you are comfortable with IP addressing schemes you can also change the inet address, the first one, to one of your choice - or keep it the same as it is. To complete the process reboot your Raspberry Pi, 

In the LX Terminal type:
sudo reboot

You are all finished, you could ping the IP address to check the settings, 

In the LX Terminal type:
ping 192.156.23.5 c-10

The c-10 only sends 10 pings!