I needed configuring my Raspberry Pi wireless interface with a static IP address. I found official instructions using wpa_supplicant.conf and dhcpcd.conf files but I preferred the usual Debian way in /etc/network/interfaces. After some try and error I made it work using the following configuration.
/etc/network/interfaces
*******************************************************************
# interfaces(5) file used by ifup(8) and ifdown(8)
# Please note that this file is written to be used with dhcpcd
# For static IP, consult /etc/dhcpcd.conf and 'man dhcpcd.conf'
# Include files from /etc/network/interfaces.d:
source-directory /etc/network/interfaces.d
auto lo
iface lo inet loopback
auto wlan0
iface wlan0 inet static
address 192.168.1.230
netmask 255.255.255.0
gateway 192.168.1.1
wpa-ssid ABCDEFGHIJK
wpa-psk xyzt
wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf
*******************************************************************
/etc/wpa_supplicant/wpa_supplicant.conf ******************************************************************* country=GB ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev update_config=1 *******************************************************************
Wireless interface will be up automaticaly at boot time. You can bring it down manually using ifdown wlan0 or bring it up using ifup wlan0 command.
Copyright (c) 2013 Ramiro Aceves . Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".