Hi,
There is a way to install vCenter with IP address instead of hostname or FQDN, but I think that there is no way to install vCenter without DNS and hostname. The hostname should be resolved by DNS.
Also, you can run DNS server on small virtual machine.
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Davoud Teimouri - https://www.teimouri.net - Twitter: @davoud_teimouri Facebook: https://www.facebook.com/teimouri.net/