Do not expect set_technology to succeed

lib/vintage_net/interface.ex

@@ -237,7 +237,7 @@ defmodule VintageNet.Interface do
   # :configuring
 
   @impl GenStateMachine
-  def handle_event(:info, {:commands_done, :ok}, :configuring, %State{} = data) do
+  def handle_event(:info, {:commands_done, :ok}, :configuring, %State{config: config} = data) do
     # debug(data, ":configuring -> done success")
     {new_data, actions} = reply_to_waiters(data)
     new_data = %{new_data | command_runner: nil}
@@ -249,8 +249,22 @@ defmodule VintageNet.Interface do
       data.config.restart_strategy,
       data.config.child_specs
     )
-
-    {:next_state, :configured, new_data, actions}
+    |> case do
+      {:ok, _pid} ->
+        {:next_state, :configured, new_data, actions}
+
+      {:error, _reason} ->
+        debug(
+          data,
+          ":configuring -> done error starting: retrying after #{config.retry_millis} ms"
+        )
+
+        {new_data, actions} = reply_to_waiters(data)
+        new_data = %{new_data | command_runner: nil}
+        actions = [{:state_timeout, config.retry_millis, :retry_timeout} | actions]
+        update_properties(:retrying, new_data)
+        {:next_state, :retrying, new_data, actions}
+    end
   end
 
   @impl GenStateMachine

lib/vintage_net/interface/supervisor.ex

@@ -42,9 +42,7 @@ defmodule VintageNet.Interface.Supervisor do
       start: {Supervisor, :start_link, [child_specs, [strategy: restart_strategy]]}
     }
 
-    {:ok, _pid} = Supervisor.start_child(via_name(ifname), supervisor_spec)
-
-    :ok
+    Supervisor.start_child(via_name(ifname), supervisor_spec)
   end
 
   @doc """