There are 3 restrictions regarding the DP Cell Manager hostname.
If these restrictions are not followed, there will be issues with the certificate creation.
Please take this into consideration before installing the product.

Hostname and domain components must start with a letter:

Certificate generation is done by the Oracle Java Security Tools (which we use in DP).
The Oracle Java Security Tools insists on strict follow of RFC 952 standard when checking for host names and domain components.
The RFC 952 insists that first character of hostname and every domain component must be letter. This is changed in RFC 1123.
There is already a request to relax the hostname handling in Oracle Java Tools to comply with the RFC 1123, but it is not resolved yet.
Source: http://bugs.java.com/bugdatabase/view_bug.do?bug_id=8054380

Hostname with underscore:

As described in RFC-0952, host names may only consist of:
A "name" (Net, Host, Gateway, or Domain name) is a text string up
to 24 characters drawn from the alphabet (A-Z), digits (0-9), minus
sign (-), and period (.). Note that periods are only allowed when
they serve to delimit components of "domain style names".
Source: https://www.rfc-editor.org/rfc/rfc952.txt

Hostname longer than 15 characters:

Windows does not permit computer names that exceed 15 characters.
Source: https://support.microsoft.com/en-us/help/909264/naming-conventions-in-active-directory-for-computers-domains-sites-and

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According to RFC 1123 for host naming.

2.1  Host Names and Numbers

      The syntax of a legal Internet host name was specified in RFC-952
      [DNS:4].  One aspect of host name syntax is hereby changed: the
      restriction on the first character is relaxed to allow either a
      letter or a digit.  Host software MUST support this more liberal
      syntax.

      Host software MUST handle host names of up to 63 characters and
      SHOULD handle host names of up to 255 characters.

      Whenever a user inputs the identity of an Internet host, it SHOULD
      be possible to enter either (1) a host domain name or (2) an IP
      address in dotted-decimal ("#.#.#.#") form.  The host SHOULD check
      the string syntactically for a dotted-decimal number before
      looking it up in the Domain Name System.

      DISCUSSION:
           This last requirement is not intended to specify the complete
           syntactic form for entering a dotted-decimal host number;
           that is considered to be a user-interface issue.  For
           example, a dotted-decimal number must be enclosed within
           "[ ]" brackets for SMTP mail (see Section 5.2.17).  This
           notation could be made universal within a host system,
           simplifying the syntactic checking for a dotted-decimal
           number.

           If a dotted-decimal number can be entered without such
           identifying delimiters, then a full syntactic check must be
           made, because a segment of a host domain name is now allowed
           to begin with a digit and could legally be entirely numeric
           (see Section 6.1.2.4).  However, a valid host name can never
           have the dotted-decimal form #.#.#.#, since at least the
           highest-level component label will be alphabetic.

QCCR2A58847 - This has not been fixed

QCIM2A79533 - This is not a fix but a check