Verified on CFME-5.8.1/RHV-4.1.3
When adding a RHV provider using a bad hostname (wrong FQDN),
the following error immediately appear in the UI:
"Credential validation was not successful: Failed to open TCP connection to bla.blab:443 (getaddrinfo: Name or service not known)"
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.
https://access.redhat.com/errata/RHSA-2017:1758