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I've installed Raspbian Jessie today and I'm having problems with an Edimax EW-7811Un 802.11n that was working under Raspbian Wheezy. It shows up fine with lsusb and sudo iwlist wlan0 shows my Wifi network (broadcast from Asus RT-AC68U) but ifconfig indicates the device isn't connecting with and obtaining an IP from the router.
Anybody have similar issues or solutions? Outputs below.
iface lo inet loopback
iface eth0 inet manual
iface wlan0 inet dhcp