Cloned from https://bugzilla.redhat.com/show_bug.cgi?id=1124466
Description of problem:

When creating a new host and from the Network tab The "suggest new" IP button is depressed and nothing happens. The text field is not filled in and there are not visual indicators if an error occured of the status of the action.

When inspecting the production log it appears a possible 404 occured that is not converted into a meaningful message:

(0.1ms)  SELECT id FROM "taxonomies" WHERE "taxonomies"."type" IN ('Location') LIMIT 1
   (0.1ms)  SELECT id FROM "taxonomies" WHERE "taxonomies"."type" IN ('Organization') LIMIT 1
  Host::Managed Load (0.3ms)  SELECT "hosts".* FROM "hosts" WHERE "hosts"."type" IN ('Host::Managed') AND "hosts"."name" = 'process_hostgroup' LIMIT 1
  Rendered common/404.html.erb within layouts/application (1.0ms)
  Rendered home/_submenu.html.erb (3.5ms)
  Rendered home/_user_dropdown.html.erb (1.3ms)
Read fragment views/tabs_and_title_records-1 (0.1ms)
  Rendered home/_topbar.html.erb (6.1ms)
  Rendered layouts/base.html.erb (7.5ms)
Filter chain halted as :find_by_name rendered or redirected
Completed 404 Not Found in 20ms (Views: 10.0ms | ActiveRecord: 1.2ms)