WLAN unknown deconfig event

[nicoeg]

Environment

• Elixir version (elixir -v): 1.8.1
• Nerves environment: (mix nerves.env --info)

Nerves environment
  MIX_TARGET:   rpi3
  MIX_ENV:      dev

|nerves_bootstrap| Environment Variable List
  target:     rpi3
  toolchain:  /Users/nico/.nerves/artifacts/nerves_toolchain_arm_unknown_linux_gnueabihf-darwin_x86_64-1.1.0
  system:     /Users/nico/.nerves/artifacts/kit_rpi3-portable-1.2.0
  app:        /Users/nico/Uptime/bricksburg/kit_os

• Additional information about your host, target hardware or environment that
  may help

Hardware: Raspberry PI 3
Network: Both wifi(wlan0) and lan(eth0) configured

Current behavior

I received this error from one of our Raspberry Pi's running Nerves. I've not been able to reproduce it, unfortunately.
Hope it can be of some use to you anyway. Let me know if not, and I'll investigate further.

[error] GenServer :"Nerves.Network.Interface.wlan0" terminating
** (FunctionClauseError) no function clause matching in Nerves.Network.WiFiManager.consume/3
    (nerves_network) lib/nerves_network/wifi_manager.ex:279: Nerves.Network.WiFiManager.consume(:up, {:deconfig, %{ifname: "wlan0"}}, %Nerves.Network.WiFiManager{context: :up, current_id: 0, dhcp_pid: #PID<0.2090.0>, dhcpd_pid: nil, ifname: "wlan0", ip_settings: %{0 => %{ipv4_address_method: :dhcp}}, settings: %{networks: [%{ipv4_address_method: :dhcp, key_mgmt: :"WPA-PSK", priority: 1000, psk: "uptime2011", ssid: "uptime.dk"}]}, wpa_pid: #PID<0.2088.0>, wpa_settings: %{0 => %{key_mgmt: :"WPA-PSK", priority: 1000, psk: "uptime2011", ssid: "uptime.dk"}}})
    (nerves_network) lib/nerves_network/wifi_manager.ex:242: Nerves.Network.WiFiManager.handle_info/2
    (stdlib) gen_server.erl:637: :gen_server.try_dispatch/4
    (stdlib) gen_server.erl:711: :gen_server.handle_msg/6
    (stdlib) proc_lib.erl:249: :proc_lib.init_p_do_apply/3
Last message: {Nerves.Udhcpc, :deconfig, %{ifname: "wlan0"}}
State: %Nerves.Network.WiFiManager{context: :up, current_id: 0, dhcp_pid: #PID<0.2090.0>, dhcpd_pid: nil, ifname: "wlan0", ip_settings: %{0 => %{ipv4_address_method: :dhcp}}, settings: %{networks: [%{ipv4_address_method: :dhcp, key_mgmt: :"WPA-PSK", priority: 1000, psk: "uptime2011", ssid: "uptime.dk"}]}, wpa_pid: #PID<0.2088.0>, wpa_settings: %{0 => %{key_mgmt: :"WPA-PSK", priority: 1000, psk: "uptime2011", ssid: "uptime.dk"}}}

Expected behavior

[trarbr]

According to the udhcpc documentation:

deconfig: This argument is used when udhcpc starts, and
when a leases is lost. The script should put the interface in an
up, but deconfigured state, ie: ifconfig $interface 0.0.0.0.

Neither DHCPManager nor WifiManager is able to consume the :deconfig event when in the :up state. I suppose the effect of crashing is that a new manager and thus a new address is leased, but perhaps it would be better to request a new lease without crashing?

[fhunleth]

I wonder if the lease ran out and udhcpc decided that it should deconfigure the interface? It seems like udhcpc should automatically start requesting an address again. Agree that it would be better to handle it than crashing.