Gfilui

I'm using an Odroid XU4 with their USB WiFi module 4 and the official Odroid distro of Ubuntu 16.04.

If I type sudo rfkill unblock wifi into a terminal, everything works fine, but I intend this machine to run headless and untethered, so that isn't a solution.

I have also already tried adding the unblock command both as a service and to /etc/rc.local. Neither worked.

Some suspicious lines from syslog:

NetworkManager[678]: <info> [1525808228.9431] rfkill0: found WiFi radio killswitch (at /sys/devices/platform/soc/12110000.usb/usb1/1-1/1-1:1.0/ieee80211/phy0/rfkill0) (driver rt2800usb)
NetworkManager[759]: <info> [1525809316.1008] (wlan0): using nl80211 for WiFi device control
NetworkManager[759]: <info> [1525809321.7019] manager: WiFi hardware radio set disabled
NetworkManager[759]: <info> [1525809321.7114] manager: WiFi now disabled by radio killswitch

As far as I know, the XU4 does not have a hardware switch to disable WiFi.

$ lsmod

Module Size Used by
fuse 86016 3
cpufreq_conservative 16384 0
cpufreq_userspace 16384 0
cpufreq_powersave 16384 0
rt2800usb 28672 0
rt2800lib 98304 1 rt2800usb
rt2x00usb 20480 1 rt2800usb
rt2x00lib 45056 3 rt2800lib,rt2800usb,rt2x00usb
mac80211 618496 3 rt2800lib,rt2x00lib,rt2x00usb
cfg80211 479232 2 rt2x00lib,mac80211
rfkill 20480 3 cfg80211
spidev 20480 0
input_leds 16384 0
evdev 24576 4
spi_s3c64xx 20480 0
gpio_keys 20480 0
uio_pdrv_genirq 16384 0
extcon_usb_gpio 16384 0
uio 16384 1 uio_pdrv_genirq
exynos_gpiomem 16384 0
ipv6 380928 46
usbhid 45056 0

$ sudo lshw -class network
USB 

 *-network:0 
 description: Ethernet interface
 physical id: 7
 logical name: eth0
 serial: 00:1e:06:32:7c:fd
 size: 1Gbit/s
 capacity: 1Gbit/s
 capabilities: ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
 configuration: autonegotiation=on broadcast=yes driver=r8152 driverversion=v1.09.9 duplex=full ip=[snip] link=yes multicast=yes port=MII speed=1Gbit/s
 *-network:1 DISABLED
 description: Wireless interface
 physical id: 8
 bus info: usb@1:1
 logical name: wlan0
 serial: 70:f1:1c:03:b3:d1
 capabilities: ethernet physical wireless
 configuration: broadcast=yes driver=rt2800usb driverversion=4.14.35-128 firmware=0.29 ip=[snip] link=no multicast=yes wireless=IEEE 802.11

$ lsusb
Bus 006 Device 002: ID 0bda:8153 Realtek Semiconductor Corp. 
Bus 006 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 005 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 002: ID 05e3:0616 Genesys Logic, Inc. hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 004: ID 046d:c05a Logitech, Inc. M90/M100 Optical Mouse
Bus 003 Device 003: ID 413c:2105 Dell Computer Corp. Model L100 Keyboard
Bus 003 Device 002: ID 05e3:0610 Genesys Logic, Inc. 4-port hub
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 002: ID 148f:5572 Ralink Technology, Corp. RT5572 Wireless Adapter
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

I logged in with a monitor and keyboard and found that there was an "Enable WiFi" menu item unchecked in the GUI. Checking that menu item seems to have resolved the problem. It looks like I could have also done this on the command line with nmcli r wifi on, if anyone else stumbles upon this question in the future.