IPv6-ready kernel. Enable IPv6 in the kernel

We can start checking for IPv6 support in the current running kernel. To check if our running kernel support IPv6 we have to look into /proc/net/ and look if there is a file named if_inet6. If this file doesn't exists the IPv6 module isn't loaded. We can try to load the module with the command modprobe IPv6. If we receive the message modprobe: Can't locate module IPv6, the IPv6 module isn't compiled, so we have to recompile the kernel to add the IPv6 module