I’ve recently had several people report that Auto Deploy is adding new hosts to their vCenter inventory using the IP address and not the fully qualified hostname.
This happens if you don’t have reverse DNS look up configured for your vSphere hosts. When Auto Deploy adds a new host to the vCenter inventory it does a reverse DNS lookup on the management IP to determine the host's Fully Qualified Hostname (FQHN). If the look up succeeds the host gets added using the FQHN, it it fails the host gets added using the management IP.
To ensure that Auto Deploy correctly adds new hosts to vCenter using the FQHN be sure to add both a forward (A record) and reverse (PTR record) DNS record for each vSphere host. For more information on setting up and testing DNS with Auto Deploy refer to the section on preparing the DNS server in the vSphere Installation and Setup guide.
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