- Create a Host
- Select the Host Group in which a VMware compute resource is used
- The request is not successful
- In the log, the following issue appears:

2019-05-24T23:01:17 [W|app|4701f1a7] Action failed
ActionView::Template::Error: uninitialized constant Fog::Compute::Vsphere::Network
Did you mean? Fog::Network
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/inflector/methods.rb:285:in `const_get'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/inflector/methods.rb:285:in `block in constantize'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/inflector/methods.rb:281:in `each'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/inflector/methods.rb:281:in `inject'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/inflector/methods.rb:281:in `constantize'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/core_ext/string/inflections.rb:68:in `constantize'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/core_ext/marshal.rb:10:in `rescue in load'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/core_ext/marshal.rb:5:in `load'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/cache.rb:804:in `uncompress'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/cache.rb:726:in `value'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/cache.rb:358:in `block in read'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/cache.rb:663:in `block in instrument'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/notifications.rb:170:in `instrument'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/cache.rb:663:in `instrument'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/cache.rb:345:in `read'
/usr/share/foreman/app/services/compute_resource_cache.rb:34:in `read'
/usr/share/foreman/app/services/compute_resource_cache.rb:19:in `cache'
/usr/share/foreman/app/models/compute_resources/foreman/model/vmware.rb:145:in `networks'
/usr/share/foreman/app/helpers/compute_resources_vms_helper.rb:77:in `vsphere_networks'
/usr/share/foreman/app/views/compute_resources_vms/form/vmware/_network.html.erb:6:in `_eb09ae03d5240a7122ea3891a470d1cc'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionview-5.2.1/lib/action_view/template.rb:159:in `block in render'

tfm-rubygem-fog-vsphere-2.5.0
foreman-1.21.3
tfm-rubygem-fog-1.42.1
tfm-rubygem-fog-core-1.45.0-3

There are similar reports:
https://community.theforeman.org/t/hammer-compute-resource-networks-id-with-vsphere-intermittent-rand/13849
https://community.theforeman.org/t/foreman-1-20-2-vmware-sporadic-http-500-when-querying-api-compute-resources-api/13907