it's not a problem to provide that information, unless you are setting up an IP based site, as opposed to a name based virtual container, which became possible with HTTP 1.1
If you do have an IP based virtual host container, and you choose not to use an FQDN, then simply let your provider know these are your intentions and I'm sure they'll make arrangements for you to leave that field blank.
Thank you for the information. But I get different information from my provider (BurstNet). They said that for DA we need two information which are IP and hostname. Kind of confuse here..
The IP is required info to keep your VPS licensed. The hostname is for informational purposes and your VPS will still be licensed even with a different hostname.
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