the Hypervisors are now also host objects since 3.0 (http://www.katello.org/docs/3.0/release_notes/release_notes.html) because content host and host objects are now unified. At the moment this means hypervisors show up as "Hosts with no reports" on dashboard. If you disable foreman reporting for the host they show up as "Hosts with alerts disabled" which is where I think they should be when they will never send reports.
this is something that has been bothering me for some time but I have worked around the issue previously: https://github.com/RedHatSatellite/katello-attach-subscription/pull/13
Because I fixed another issue with the virt-who checkins I came across the code again and I've decided to suggest a fix for the issue because I think its just a one-liner :)
The more general question is if my thought is correct - I only use vmware hypervisors where they really will never send any reports but if you have another hypervisor that does checkin with foreman it may be wrong. Thats why I decided to put it into the create of a hypervisor - this should only happen when the hosts are normally not managed by foreman ie the will never send reports.
Created from redmine issue http://projects.theforeman.org/issues/20727
requested by support
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA.
For information on the advisory, and where to find the updated files, follow the link below.
If the solution does not work for you, open a new bug report.