When you have a host in Foreman which is a HyperVisor and it needs to load lots of interfaces because of the vlans that are hosted on this Hypervisor the webbrower times out on loading.

The hostpage itself loading actually works but it takes minutes!, when you try to edit the host the webgui finally times out on the Interfaces Tab with this as result in the production.log

2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.5ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (74.5ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (68.1ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (3.2ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.4ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (75.8ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (83.1ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (4.0ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.6ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (93.0ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (80.6ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (4.0ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.6ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (90.1ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (79.4ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (3.9ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.6ms)
2017-01-23 03:01:09 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (89.0ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (79.4ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (3.9ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.6ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (89.0ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (74.5ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (3.3ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.4ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (82.8ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (64.7ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (3.1ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (9.6ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (81.8ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (69.0ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (3.1ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.4ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (76.7ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (64.1ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (3.0ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.5ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (71.4ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (63.9ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (3.1ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.5ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (71.3ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (77.9ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (3.3ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.4ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (86.0ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (65.2ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (3.1ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.5ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (72.6ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (63.7ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (3.0ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.4ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (70.9ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_base_form.html.erb (63.6ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_virtual_form.html.erb (3.1ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/_provider_specific_form.html.erb (0.4ms)
2017-01-23 03:01:10 b9d8a62a [app] [I] Rendered nic/manageds/_managed.html.erb (70.9ms)
etc...