Q122900: Can’t Use Periods in DNS Host Names

Article: Q122900
Product(s): Microsoft Windows NT
Version(s): WINDOWS:95; winnt:3.5
Operating System(s): 
Keyword(s): kbenv
Last Modified: 08-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Workstation version 3.5 
- Microsoft Windows NT Server version 3.5 
- Microsoft Windows 95 
- Microsoft Windows 98 
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SUMMARY
=======

Both the Help file and the manual for the TCP/IP Domain Name Server (DNS)
configuration are incorrect in describing the type of characters that can be
used in the host name. The documentation says that both the hyphen and period
can be used. However, attempting to use a period in the host name will result in
an error message indicating the parameter is incorrect.

The TCP/IP manual says:

  In the DNS Configuration dialog box, you can, optionally, type a name in the
  Host Name box (usually your computer name):

  The name can be any combination of A-Z letters, 0-9 numerals, and the hyphen
  (-) plus the period (.) character used as a separator. By default, this value
  is the Windows NT computer name, but the network administrator can assign
  another host name without affecting the computer name.

The Help file says:

  Host Name

  Optionally, type a name in the Host Name box (usually your computer name). The
  name can be any combination of A-Z letters and 0-9 digits, plus the hyphen
  (-) and period (.) characters.

  Using a period in the host name would be interpreted as a separator, and
  result in an error message.

RFC 952 says:

  Periods are only allowed when they serve to delimit components of "domain
  style names".

The Windows 95 Resource Kit states:

To set the host name for DNS

Type a name in the Host Name box.

The name can be any combination of the letters A through Z, the numerals 0
through 9, and the hyphen (-), plus the period (.) character used as a
separator. By default, this value is the Microsoft networking computer name, but
the network administrator can assign another host name without affecting the
computer name.

Note: Some characters that can be used in computer names, especially the
underscore, cannot be used in host names.

The Windows 98 Resource Kit states:

Microsoft TCP/IP Protocol

Using DNS for Name Resolution

Configuring DNS

To set the host name for DNS

Type a name in the Host box. The name can be any combination of the letters A
through Z, the numerals 0 through 9, and the hyphen (-), plus the period (.)
character used as a separator. By default, this value is the Microsoft
networking computer name, but the network administrator can assign another host
name without affecting the computer name.

MORE INFORMATION
================

Under Windows NT 3.5, the host name is set to the computer name (or NetBIOS
name) by default. You can change the name used from the Network section of
Control Panel. Select TCP/IP Protocol, choose Configure, and then choose DNS to
see the host name. You can specify both the host and domain names.

NOTE: The domain name listed here should not be confused with the term "domain
name" as it is used in a Windows NT domain. This is the domain name set by the
TCP/IP DNS.

Reference(s):

More information on DNS can be found in the DNS RFC 1034.

Additional query words: prodnt

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Keywords          : kbenv 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNT350search kbWinNTW350 kbWinNTW350search kbWinNTSsearch kbWinNTS350 kbWinNTS350search kbWin95search kbWin98search kbZNotKeyword3 kbWin98
Version           : WINDOWS:95; winnt:3.5

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