Setting a static IP in Kali is useful for a lot of things. You may want to forward ports from your router to serve web pages, use SSH from outside your local network or set up some sort of media server.
For whatever reason, Kali is trying to make our lives easier by introducing graphical tools to be used by default but kind of making our terminal life a bit harder! :p
## The primary network interface
auto eth0
iface eth0 inet static
address 192.168.1.101
netmask 255.255.255.0
gateway 192.168.1.1
nameserver 8.8.8.8
auto eth0
iface eth0 inet static
address 192.168.1.101
netmask 255.255.255.0
gateway 192.168.1.1
nameserver 8.8.8.8