Hostname requirements
----------------------

* Hostname should not contain the following characters: ``, (comma)``, ``. (period)``, ``_ (underscore)``.
* Hostname cannot start or end with a hyphen ``(-)``.
* No upper case characters are allowed in the hostname.
* Hostname cannot start with a number.
* Hostname and domain name (``hostname00000x.domain.xxx``) cumulatively cannot exceed 64 characters.