control: disabled routing to unknown DRBD state

lib/ha_handler/control.ex

@@ -154,7 +154,17 @@ defmodule HAHandler.Control do
           )
 
         unknown ->
-          Logger.warning("Unhandled DRBD/HAProxy state: #{inspect(unknown)}")
+          Logger.warning("Unknown DRBD/HAProxy state: #{inspect(unknown)}")
+          Logger.info(
+            "Disabling routing SSHFS to (likely) failed #{drbd_instance.haproxy_server}."
+          )
+
+          HAProxy.set_server(
+            @haproxy_drbd_backend,
+            drbd_instance.haproxy_server,
+            "state",
+            "maint"
+          )
       end
     end
   end