[raspbian] Update documentations

Author: Ritwick DSouza

docs/source/backends/raspbian.rst

@@ -387,27 +387,36 @@ You can install it using this command::
   modes
 * **dnsmasq** - The package converts the Raspberry Pi into a DHCP and DNS server
 
+Since the configuration files are not ready yet, turn the new softwares off as follows::
+
+    $ sudo systemctl stop dnsmasq
+    $ sudo systemctl stop hostapd
+
 Configure your interface
 ~~~~~~~~~~~~~~~~~~~~~~~~
 
 Let us say that ``wlan0`` is our wireless interface which we will be using.
-First we need to setup a static IP for our wireless interface. Edit the
-``wlan0`` section in interface configuration file ``/etc/network/interfaces``::
+First the standard interface handling for ``wlan0`` needs to be disabled.
+Normally the dhcpcd daemon (DHCP client) will search the network for a DHCP server
+to assign a IP address to ``wlan0`` This is disabled by editing the configuration
+file ``/etc/dhcpcd.conf``.
+Add ``denyinterfaces wlan0`` to the end of the line (but above any other added
+``interface`` lines) and save the file.
 
-    auto wlan0
-    iface wlan0 inet static
-    address 172.128.1.1
-    netmask 255.255.255.0
-    network 172.128.1.0
-    broadcast 172.128.1.255
 
-Reload ``wlan0`` interface with ``sudo ifdown wlan0; sudo ifup wlan0``
+To configure the static IP address, create a backup of the original
+``/etc/network/interfaces``. Then replace the the file with the one generated
+by the backend. Now restart the dhcpcd daemon and setup the new ``wlan0`` configuration::
+
+    sudo service dhcpcd restart
+    sudo ifdown wlan0
+    sudo ifup wlan0
 
 Configure hostapd
 ~~~~~~~~~~~~~~~~~
 
 Create a new configuration file ``/etc/hostapd/hostapd.conf``. The contents of this
-configuration will be generated by the render method using NetJSON DeviceConfiguration.
+configuration will be generated by the backend.
 
 You can check if your wireless service is working by running ``/usr/sbin/hostapd /etc/hostapd/hostapd.conf``.
 At this point you should be able to see your wireless network. If you try to connect