The following are the reasons for which a new license is required. Changes to: The operating system The CPU count -The FQDN (Fully Qualified Domain Name) of the machine on which the license is installed If the subdomain change does not alter the FDQN then a new license should not be required.
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A fully qualified domain name (FQDN) is the complete domain name for a specific computer, or host, on the internet. The FQDN consists of two parts: the hostname and the domain name. For example, an FQDN for a hypothetical mail server might be mymail.somecollege.edu. The hostname is mymail, and the host is located within the domain somecollege.edu.

Anatomy of a URL

